Usenet 1994 January/usenetsourcesnewsgroupsinfomagicjanuary1994.iso/answers/ibm-rt-faq/hardware

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Path: senator-bedfellow.mit.edu!bloom-beacon.mit.edu!gatech!swrinde!cs.utexas.edu!wotan.compaq.com!moxie!lobster!antimatr!faq-rt
From: [e-mail] (Mark Whetzel)
Newsgroups: comp.sys.ibm.pc.rt,comp.answers,news.answers
Subject: COMP.SYS.IBM.PC.RT: IBM RT - Hardware - Frequently Asked Questions
Summary: This posting contains a list of Frequently Asked Questions
         (and their answers) and general information, hints and tips
         for using IBM RT 615x computers.
Keywords: IBM RT PC hardware FAQ 6150 6151 6152 AIX VRM AOS MACH PICK
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Date: 2 Nov 93 02:01:00 GMT
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Archive-name: ibm-rt-faq/hardware
Last-modified: Tue Nov  2 00:34:03 CST 1993
Version: 2.0

Frequently Asked Questions for:  IBM RT system hardware

Posted around the first of each month to comp.sys.ibm.pc.rt.

This is the first of three FAQ articles dedicated to the IBM RT processor.
The other FAQ articles are dedicated to aspects of the RT processor when used
with different operating systems.
AIX issues will be filed in the archive name:  ibm-rt-faq/aix
AOS issues will be filed in the archive name:  ibm-rt-faq/aos

 [ Note: The AIX and AOS FAQs are not yet ready.. sorry for the
   delay in getting them posted...  MW ]

This particular file will cover general hardware questions about the
IBM RISC processor known as the RT PC.  The IBM RT is known also as
an IBM model 6150, 6151 or 6152 machine.

The hardware information presented here is intended to be independent of
the operating system that is running on the system.  There are several
companion articles I have compiled on operational differences of the RT
hardware and software when being used with the different operating systems
available.  If you notice a particular hardware feature that is only
supported under one particular OS, let me know, and I will move it to
the appropiate OS specific list.

This list is organized as a digest for newsreaders that can handle it.
Each "digest page" generally covers one topic or Question/Answer .

You can jump to a particular topic by searching for that index key
(such as H.10) in position 1 of this list.

Direct inclusions of information by some submitters is framed with a
line of "==**==**" repeating across the page.

In order to build up a better FAQ base, E-mail your contributions.
I will respond back to you via mail on your submission.
This FAQ is a work in progress.  Some entries are incomplete, and other
information may be missing.  Places with ????? denote areas needing
more work or information.  Areas that I have made personal comments
on are enclosed in square brackets [].

For AIX RT  submissions E-mail to:   [e-mail]
For AOS RT  submissions E-mail to:   [e-mail]
For MACH RT submissions E-mail to:   [e-mail]
For general Q&A submissions (hardware and other stuff) E-mail to:
   [e-mail]

Input is always welcomed for making this a better list.
Style, grammar and spelling notes are also welcome.  Sometimes
it seems that my brain operates faster than my fingers can type. :-)

Other comments and correctons should be sent to the author:
    Mark Whetzel
    DOMAIN addr: [e-mail]
    BANG address:  ..!menudo!lobster!antimatr!markw
    Daytime work number  8AM-5PM CST Mon-Fri  VOICE: [phone]

 ___--___---___--___---___--___---___--___---___--___---___--___---___--___

Changes for this November posting:
   1) Due to popular demand, removed all 'tabs' from the file, and
      replaced with spaces.
   2) Section H.7 updated to include the:
      Jumper information for E70, E114 hard drives.
      Required jumper settings for E70, E114 and E310 hard drives.
      REQUEST: Anybody know the meanings of the 7 switches for the
        E310 hard drive?
   3) H.6  section updated with discontinuance dates for selected
           IBM perhiperials and monitors.
   4) H.36 section on Token-Ring jumper and addressing information.
   5) H.37 section added with greater detail on differences between
           the different processors.
   6) H.38 section added discussing the different FP options and boards.
   7) Additional notes and warnings on the processor upgrade section added.
   8) H.39 section added on battery replacement.
   9) H.15 section updated on Megapel DAC information and RPQ information.
  10) H.34 section on 5081 updated with RPQ information.

 ___--___---___--___---___--___---___--___---___--___---___--___---___--___

-------------------------
Index to the IBM RT - Hardware FAQ.

  1.0   General Hardware questions

        H.1   What is an IBM RT and some of its history?
        H.2   What types of processors were made?
        H.3   How fast are the different models of RT?
        H.4   Can you upgrade from one processor type to another?
        H.5   How can I tell what kind of processor type is installed?
        H.6   Where can I get parts for RT systems?
        H.7   What adapter cards are supported in an RT running AIX V2.
        H.8   What IBM perhiperials were available?
        H.9   What cables are available?
        H.10  What is the pinout of the 6150 serial ports?
              How do I make my own RS232 cables compatible for use with AIX.
        H.11  What is the pinout of the 6150/6151 Mouse/Tablet port?
        H.12  What is the pinout of the 6150/6151 keyboard port?
        H.13  Can I use a Non-RT keyboard on an RT?
        H.14  How do I get a parallel printer attached to an RT?
        H.15  What are the switches on the Megapel adpater for?
                Technicial information on Megapel adapter and display.
        H.16  AT Co-Processor information.
        H.17  How can I get the maximum data on a 6157 tape drive?
              (Also covers different types of tapes to use.
               flags for 'backup' and 'tar'.)
        H.18  What hard disks can be used in an RT?
                What value is the ESDI terminator resistor for an E70 drive?
                Switch settings for the E70 and E114 drives.
        H.19  What is the difference between an R70 and an E70 disk drive?
        H.20  What are the characteristics of the various IBM RT disk drives?
        H.21  What SCSI devices can be attached?
        H.22  What do the LED codes mean during power on.
        H.23  What does LED code xx mean (during runtime)?
        H.24  What is different about the RT I/O slots.
              What cards will run in slot 8.
        H.25  How do I run diagnostics.
        H.26  Serial port cards maximums and limitations.
        H.27  What are the switches on the 3278/79 adpater?
        H.28  Jumper location and information on AT Fixed disk adapter.
        H.29  Jumper locations and information on ESDI adapter.
        H.30  Jumper locations and information on EESDI adapter.
        H.31  Jumper locations and information on the 'PORTED' EESDI adapter.
        H.32  IBM 9332 Disk drive information.
        H.33  Pin connections and technical information on 6153, 6154 and
              6155 monitors.
        H.34  5081 Display technical information.
        H.35  Jumpers and documentation on the Ungermann-Bass/IBM
              ethernet board.
        H.36  RT Token Ring card jumpers and addressing.
        H.37  What are the differences between the 032, APC and EAPC
              processor types.
        H.38  Speed and capability of the Floating Point options for
              the RT computers.  FPA, MC68881, AFPA.
        H.39  Where can I obtain a replacement battery?

  9.0   Credits, Acknowledgements and other information.

        X.1   Acknolowgements and copyright information.

-------------------------
H.1 - What is an IBM RT and some of its history?

   The IBM RT is a RISC based processor designed by IBM, and unique to
   that platform.  The RT was first announced by IBM in January 1986.
   The processor is generally refered to as 032 processor.  In some
   documentation it is also refered to as the 'ROMP' processor.

   [ I have had some excelent feedback on the ROMP name and a little
     on RT history. See the submissions in this section below my notes for
     some intresting information. More information on RT history is always
     welcomed. - MW ]

   The RT PC Advanced System Processor has a 32-bit Reduced Instruction
   Set Computer (RISC) architecture developed by IBM and implemented in
   a 1-micron CMOS technology.  It has sixteen 32-bit general purpose
   registers and uses 32-bit addresses and data paths. The
   microprocessor is controlled by 118 simple 2- and 4-byte
   instructions.  An IBM-developed advanced memory management chip
   provides virtual memory address translation functions and memory
   control.  It provides a 40-bit virtual address structure capable of
   addressing one terabyte of virtual memory. Internal processor
   organization enables the CPU to execute most register-to-register
   instructions in a single cycle.
          The model 115/125 RT PC with their FAST ECC memory, is capable
   of providing the processor with a 32-bit word of data plus ECC each
   100 nsec cycle.  This memory consists of 40 1-megabit IBM RAM chips.
   These chips are the same megabit technology used in the IBM 3090.
   The model 130/135 version of the processor uses an 80 nsec cycle time
   with the maximum of 16 Megabytes of real memory installed on the
   processor card.

   The IBM RT has had a varied life even from its initial announcement.
   Most industry watchers considered the RT as "not enough power, too high
   a price, and too late".  Many thought that the RT was part of IBMs
   Personal Computer line of computers.  This confusion started with its
   initial name, "IBM RT PC". Initially, it seemed that even IBM thought
   that it was a high end Personal Computer given the initiallly stunning
   lack of support that it received from IBM.  This confusion even was
   reflected in the design of the manuals for the RT, they are the same
   odd size three ring binder (except longer), with slip cases like the
   original IBM PC manuals.  Condidering the RT systems modest processing
   power (when first announced) coupled with announcements later that year by
   some other workstation vendors made most industry analysists
   question IBMs directions.  To be fair, AIX for the RT was IBMs first
   *PUBLIC* foray into UNIX.  IBM had a very tough task ahead of them,
   completely changing how traditional UNIX design had been done.  The VRM
   (Virtual Resource Manager) is the real operating system of the RT, and
   controls all the hardware.  AIX is running as a guest OS, in a similar
   fashion to the VM product of IBMs mainframe processors.
   The lack of software packages and IBMs somtimes lackluster support of
   AIX, plus the sometimes unusual changes from traditional UNIX operating
   system defacto standards caused most software suppliers to be slow to
   embrace the RT and AIX.  The RT found its home mostly in the CAD/CAM
   and CATIA areas, with some inroads into the Scientific and educational
   areas, especially after the announcement of AOS and substantial discounts
   for the Educational community.
   The RT also found use as shopping store control systems, and interface
   system between IBMs larger mainframes and some of its point of sale
   terminals, store control systems and also machine shop control
   systems.

   One of the RT systems claim to fame was its use as packet switch hubs for
   part of the internet backbone, utilizing specially designed hardware
   communication sub-processors and specially written operating system control
   software.
   [More information on this would be welcomed! Start/stop dates,
    number of machines used per node and netwide, ect.. - MW]

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: David Snearline <[e-mail]>

   NSFnet used the 6151 desktop model RT systemss for the NSS's (Nodal
   Switching Stations).  Each RT in the group had two interface cards:
   one IBM token ring, and one other interface (ethernet, T1, etc).
   A typical NSS would look like:
                          +---- local ethernet
                          |
                        +---+
                        |   | IBM RT
                        |   |
                        +---+
                         | |
                         | |  +---+ IBM RT
                         | +--|   |
        Token Ring ----> +----|   |---- T-1 to another NSS
                              +---+
        (more RTs here)

   Except for backup links in some places, most of the RT NSS's have been
   replaced by RS/6000's, which have all of the cards in one workstation.
   Most of the RTs are sitting around, waiting to be used for parts or
   dismantled.  ANS/Merit could probably give you more details on when this
   switchover occurred, but I believe that November 1992 was one of the
   official changeover dates.

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: <[e-mail]> (Gerald Oskoboiny)
     Last night I was reading "Computer Wars" by Charles H. Ferguson and
     Charles R. Morris (ISBN 0812921569, Random House, 1993), and it has
     the code names of the RT and other projects. I forget most of the details,
     but it is very interesting reading. It explains how IBM had RISC
     technology in 1968 but mismanaged it until the disappointing RT was
     released in 1986.  As far as "history of the RT" goes, this book explains
     it all.

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: [e-mail] (Mike Johnson)
   Newsgroup: comp.arch    Subject: Re: First Commercial RISC Computer

    That's Research OPD Mini Processor.  OPD = Office Products Division.

    ROMP was originally designed to be used in office products, primarily
    text editing systems such as the IBM Office System/6 and DisplayWriter.
    The architectural work started in late spring of 1977, as a spin-off of
    the T.J. Watson Research 801 work (hence the "Research" in the acronym).
    Most of the architectural changes were for "cost reductions," such as
    adding 16-bit instructions for "byte-efficiency"--a main concern at IBM
    at the time.

    The first chips were working in early 1981.  The delay from architecture
    to working chips was caused mainly by building two models of the chip in
    TTL: an emulator that just executed the instruction set and a
    nodal-equivalent model that was more-or-less an exact duplicate of the
    chip (about 6000 7400-series DIPs plus a number of IBM bipolar gate
    arrays and static RAMs).  The delay was also caused by two major revs to
    the architecture: one change to a 32-bit architecture from a 24-bit
    architecture (I'm serious), and another to support demand paged
    virtual memory (the implementation supported out-of-order loads, so
    precise interrupts were hard to come by).

    ROMP was arguably the first working commercial RISC.  The arguments
    would be over whether or not it was a "true" RISC and whether or not
    one could count it as a commerial product in 1981, since it didn't
    actually ship until 1986.  *This* delay, in my opinion, was caused by
    overly ambitious software plans, in the form of porting an IBM version
    of UNIX to a virtual software layer called VRM (Virtual Resource
    Manager), rather than porting Berkeley UNIX directly to the hardware.
    The path from having hardware to developing VRM to porting UNIX and
    then getting VARs to write applications was just too long--a problem
    that IBMs resources couldn't overcome.

    I was the first member of the ROMP design team--something I credit to
    random chance rather than any personal expertise (my graduate work
    at the time had been in digital control systems).  ROMP was a good way
    to learn microprocessor design by learning what *not* to do.

    I understand that ROMP was also used in an IBM laser printer, but I
    don't have any first-hand knowledge that this is true.
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

-------------------------
H.2  - What types of processors were made?

   There are 2 basic types of machines called an RT.
   The tower model, IBM machine number 6150.
   The desktop model, IBM machine number 6151.

   There exists a special version machine that used the same processor,
   available only to educational sites that is a hybrid IBM PS/2 model 60
   with a special mirco-channel board version of the 032 processor,
   dubbed as a 'crossbow' board. [project name? -MW]
   That machine was IBM machine number 6152.  The 6152 ran only the AOS
   operating system downloaded from another IBM 6150 or 6151 also running
   AOS, via a lan TCP/IP interface (either Token-ring or Ethernet).
   Later versions of AOS could be loaded directly on the 6152 once larger
   hard disk drives for PS/2 became available.
   The availablity of support for VGA adapters in the X11 releases was because
   of the existance of this machine.

   I am not sure the 6152 machine can rightly be called an RT, as the
   only interface boards used were the same as used in PS/2 machines.
   This version may be somewhat rare, and I have never seen one.
   The rest of this list will not cover the 6152 machine.
   More information on the 6152 processor is covered in the AOS FAQ
   posting in this newsgroup.  The 6152 model was discontinued by IBM
   as of August 31, 1990.

   [ More details about the mysterious 6152 model RT would be intresting.
     How widespread is it?  History? Are any still running? - MW ]

   There are three versions of the 6150/6151 processor card, and several
   unique RT models using each version of the card.  IBM used the different
   model numbers to designate different base configurations of
   processor speed, installed main memory and installed hard disks.
   Model nubmers can be deciving, as some machines may have been
   field upgraded to different models and/or processor types.

   The standard 032 processor card was in models:
     10, 15, 20, 25 and A25.
      - 1MB memory was standard, with expansion available,
        via 1MB, 2MB or 4MB memory boards.
      - Optional Floating Point Accelerator was also available.
      - AIX 1.0 and 1.1 (RT version) initially shipped with these models.
      - 170ns processor cycle time.

      - The models 10, 20 and A25 were discontinued October, 1988.
      - The models 15, and 25 were discontinued May, 1990.

   The Advanced processor card was in 2 different types:
     The 115 which had 4MB memory ON the processor card,
     available only on the desktop 6151.
     The 125 and B25 models which had all their memory on external
     FAST ECC 4MB memory cards, used in the 6150 tower models.
      - Memory expansion via 4MB FAST ECC memory boards.
      - Built in 20Mhz Motorola 68881 floating-point processor.
      - Optional Advanced Floating Point Accelerator was also available.
      - These models required AIX 2.1 as a mininum.
      - 100ns processor cycle time.

      - Later 8MB FAST ECC memory boards became available.
      - The models 115, 125 and B25 were discontinued May, 1991.

   The Enhanced Advanced processor card:
     Available only with the model 135 and B35 (6150 tower), and with
     the model 130 (6151 desktop).
      - On-board 16 MB main memory standard.
      - Motorola 68881 was removed and the Enhanced Advanced Floating
          Point Accelerator was made a standard feature.
      - These models required AIX 2.2 as a mininum.
      - 80ns processor cycle time. (Much faster!)
      - Rated by IBM at 5.6 Mips.
      - The models 130, 135 and B35 were discontinued May, 1991.

   Enhanced Advanced processors are easily recognized. Soldered directly
   to the processor board are 20 'SIMM like' memory boards sticking up on
   about 1/2 of the processor card.  All processor cards are installed
   in the special board slot labeled 'A'.

   The A## and B## model machines shipped without the native keyboard, and
   instead used a preinstalled 5080 attachment interface card allowing the
   RT processor to share the keyboard that was attached to the 5080
   graphics system hardware.  Via a special interface card, the 5080
   lighted program function keypad (LPFK) and dials unit (three variable
   position X,Y and Z controls) could be attached either to the RT or
   the 5080 graphics system.  Primarly used in a CADAM and CATIA setup
   running AIX.

   System processor board timings:
        Board            Bus Cycle time      Memory Bandwith
                         (nanoseconds)       (Megabytes/second)
        Original 032         170                    23.5
        Advanced             100                    40
        Enhanced Advanced     80                    50

-------------------------
H.3 - How fast are the different models of RT?

    [ I would like to see some results from users with later benchmark
      tests on both the native C and Fortran compilers.
      Tests with a 135 processor using the last available compiler patches
      from IBM, and side-by-side tests with the now available GCC compiler
      for AIX RT would be an intresting addition to this section.
      I would like to see how those compilers stack up to each other
      in performance tests.  I would also like to see how the RT still
      stands using some of the newer industry standard benchmark programs.
      Comparisons against other popular processors now in use would be
      intresting.  This information may be dated, considering that IBM
      continued to improve the performance of the native C compiler
      available with the AIX V2 operating system.

      Comparison running AOS or MACH would also be intresting to see how
      much difference compiler and OS technology has on overall performance.
      Challenge anyone?  - MW ]

    Note: These performance numbers are dependent on various factors,
          including complier update levels, language, Fortran or C,
          compiler options, and instlled floating point accellerators.
          Times given are using the AIX operating system.
          These numbers were obtained from an IBM announcement letter
          number 188-120 Dated July 19, 1988, announcing the release
          of the 135 Enhanced Processor.
          Refer to that IBM announcement for more complete information.

   Test                         Jan 86          Feb 87          July 88
   =====================+===================================================
   Dhrystones           |       1780            6500             8300 (1)
                        |                                       10400 (2)
   =====================+===================================================
   FP KWhetstones       |
    (double precision)  |
        Standard        |       20K             810K            2020K
        Optional        |       200K            1600K           N/A
   =====================+===================================================
   LINPACK KFlops       |
    (double precision)  |
        Standard        |       --              80K             410K
        Optional        |       37K             300K            780K (3)
   =====================+===================================================
   Disk Maximum         |
     - Capacity         |       210Mb           5810Mb          7460Mb
     - Data Rate        |
       (Mbytes/sec)     |       0.26            1.08            1.08 (4)
   =====================+===================================================
   Notes: (1) Benchmark run on an RT System model 125.
          (2) Benchmark run on an RT System model 135.
          (3) Using specially coded basic linear algebra subprograms.
          (4) 310 Meg Fixed disk has a 928 Kbps data rate.

    The date in the columns above refer to IBM announcement letters
    for the RT, released on the the date indicated.

    Jan 86   generally refers to the Standard 032 processor
             available with models 10, 15, 20, 25 and A25.
    Feb 87   generally refers to the 115 and 125 models and AIX V2.1
             enhancements.
    July 88  refers to the announcment of the 130, 135 and B35 models,
             and AIX V2.2 enhancements.

    The IBM announcment letter partially quoted above indicates that the
    benchmarks were achived by running the Dhrystone benchmark V1.1 on
    AIX/RT Operating system V2.2 after installing the June 1988 updates
    to the C compiler.

-------------------------
H.4 - Can you upgrade from one processor type to another?

   The general answer is yes. However, this is dependent on two things:
   1) If you can find the necessary parts.
   2) If the planar is of a particular hardware level.

   The memory cards in the models earlier than the 115/125 are too slow
   for the later Advanced Processor (125).  That processor will only
   allow use of the 'Fast ECC' memory cards available in either 4MB
   or 8MB sizes, for a total of 16 Meg.  If you have a two different sizes
   of memory cards, the larger must be in slot 'C'.
   The 135 model has all 16 Meg available SOLDERED to the processor
   card and require no external slot C or D installed memory.

   The Floating Point Accellerators only work when matched with the
   correct type of processor.

       Standard processor = Standard FPA or either a level1 or level2 AFPA.
       Advanced processor [APC] (115,125 or B25) = Advanced FPA (level1 or 2).
       Enhanced Advanced processor (130,135,B35) = Enhanced Advanced FPA
                (level 2 board only).

   The standard FPA board is easily recognized as it is a single board, and
   the slot fingers are uniquely placed so as to fit only in slot B on the
   6150 and 6151.  The later model AFPA is a double layer board, constructed
   so as to still fit in one slot.  Descriptions of level1 and 2 FPA boards
   are described in the adapters section (H.7) below.

   To perform an upgrade from the slower version of the 032 processor to
   the APC (115/125) needs different Fast ECC memory cards, and a optionally
   a faster FPA. To upgrade from a APC to an EAPC (130/135), you must remove
   any installed memory boards because the EAPC has onboard memory.  The
   Enhanced processor also requires Enhanced FPA (level 2 version ONLY).
   The faster processors also require later versions of AIX upgrades
   that were minimum for each model, and the appropiate minimum memory
   for the type of processor.  AOS has a compile flag for the kernel
   use on the faster processsors.  See the appropiate OS faq for more
   specific information.

   NOTE: The EARLY model APC card had 4 Meg bytes of memory ON the procssor
   card.  It looks like a small array of metal can chips about 1/2 inch square
   covering the right half of the processor board.  It is the ONLY APC card
   that will work with ALL boards removed.  Later model APC cards RELIED on
   memory on the processor bus (Slots C and D) and *WILL NOT* work with no
   memory installed.  With NO memory installed in slots C and D you will
   ALWAYS stop with a 5c LED code, as the processor has no memory!
   If you have an early processor board, then you must NOT have two 8Mb boards
   installed, otherwise there will be a memory address conflict with the
   last board! You will need a 8Mb board and a 4Mb board for that setup.
   NOTE2: A Maxmum of 16 Mbytes of main memory is supported by the RT
   hardware.

   When using 'Enhanced ECC memory' boards, make sure that the jumper
   on the memory cards is in the 'fast' position.  The undocumented jumper
   allows the newer cards to work with the older processors by moving
   it to the 'slow' position.  If the memory boards are of different sizes,
   make sure the LARGER one is in slot C, and the smaller in slot D.
   To run an APC card requires att least 4 Mb of memory and AIX 2.1 or later
   for the OS version.

   As shipped from IBM the APC 125 model upgrade kit was IBM part Number
   61X6833 and included the following:
      - New processor board
      - Fast memory
      - Extended ESDI adapter card.
      - Extended ESDI cable harness.
      - A reformat utility on a bootable diskette to make the earlier R70
        drives to E70 format.
      - An AIX 2.1 upgrade had to be co-ordered.  You MUST be using AIX 2.1
        or later to support the APC and AFPU cards.  (models 115 or 125).

   Users without ESDI cards had to buy an E70 drive, minimum to upgrade.
   The R40 drive and MFM controller had a maximum of one drive supported
   when moved to the secondary slot and jumpering.

   I do know that the upgrade kit, when ordered needed the base serial number
   of the machine as part of the order, and that serial numbers BELOW
   a selected value were a different upgrade.  However, the upgrade
   announcement letter (187-022) does NOT mention a planar upgrade in
   its text.

   The only planar problem I know of was with REAL old model RT's not
   working with ethernet adapters.. here is a cut of the 6150 model
   hardware information..dated Feb 26, 1991.

   ================= start cut of IBM info ===============================
   Hardware Requirements:  The Baseband Adapter will plug into any model of the
   6150 and 6151 system units.

   Software Requirements:  This product requires that the RT AIX Operating
   System Version 1.1 (59X8994) be installed.

   Limitations:  The Baseband Adapter must NOT be plugged into slot 8 on the
   6150 Models 020, 025, and A25, or slot 5 on the 6151 Model 010.

   Planar must be at, or higher than, EC A31282M on the 6150 Models 020, 025,
   and A25, or EC A31283M on the 6151 Model 010.  If the customer serial number
   is 3500 or lower on Models 020, 025, and A25, or lower than 2250 on Model
   010, have them contact IBM for an upgraded planar board.  There will be an
   "Attention" card placed in each Baseband Adapter box.  The upgraded planar
   board will be installed at no charge to the customer.
   ================= end cut of IBM info ===============================

   [ I am still searching for more complete upgrade information.
     IBM had some specific minimum planar serial numbers that
     were required for the faster processors, but I do not have
     any of that information.  Anybody? - MW ]

-------------------------
H.5 - How can I tell what kind of processor type is installed?

    For a quick determination of the processor type, observe the LED digits
    during a power on IPL.  The general sequence for initial 'Power On
    Self Tests' (POST) codes is:
       88, xx, zz, yy, 09, 10, 14 (long), 15, 16, 21, 22

    The XX, YY and ZZ LED values will have a value of:
        XX  YY  ZZ
        01  03  05  = Standard 032 processor. (010,020,025,A25)
        1c  3c  5c  = Advanced 032 processor. (115,125 and B25)
        1u  3u  5u  = Enhanced Advanced 032 processor. (130,135,B35)

    The XX and YY codes stay around the longest, and are easiest to see.
    A few other codes fly by as well, but try as I could, I could not
    tell what they were.  Other codes can show up, depending on what other
    I/O boards are found in the system during power up.  If any code
    remains in the LED display for over 5 minutes, a failure had been found
    with the system during self tests.  All LED codes after the code 22
    (boot record processing), are dependent on the operating system being
    loaded into the RT.  LED codes prior to the 22 are placed in the LED
    display by the Power On Self Tests (POST) of the RT planar.  Almost
    all the other LED codes are displayed by Loadable POST (LPOST) routines
    invoked during VRM initialization and IPL.  Obviously systems NOT
    running AIX with VRM will have different LED codes.

-------------------------
H.6 - Where can I get parts for RT systems?

    [ This section needs more entries, addresses and/or phone numbers.
      Third party suppliers or used equipment dealers known to deal
      in RT hardware would be great. - MW ]

    Parts at this time are still available from IBM.
    At this time, IBM does not have any announced discontinuance of
    individual parts.

    As of September 15, 1993, IBM has announced (letter 193-161 dated
    June 15, 1993) discontinuance of selling all the different monitors
    (6153, 6154, 6155, 5081) and some of the external perheriperials
    (6156, 6192).  The 6157 tape drive was discontinued earlier in the
    year.

    IBM still offers maintence contracts for RT computers and equipment.

    IBM parts may be ordered by calling IBM-Direct, 1-800-426-2468.

        Other IBM numbers:
        1-800-426-7378  Service/Maintenance
        1-800-426-2468  Supplies/Dealer Referral
        1-800-426-3333  Information

    However, IBMs prices may be a little steep.

    Some used and surplus parts houses from time to time get RT systems,
    but not on any regular basis.  Lots of times, they are broken up for
    some of the re-usable parts, and the rest junked. :-(

    Dickens Data Systems used to make special 8, 16 and 64 port async
    adapters for RT systems. They also sold device drivers for various SCSI
    attached devices, including 9-track tape.  I am not sure if they
    still make any of these.

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter:  [e-mail] (Richard Rogers)

       [ I have made a few editorial changes and corrections to
         Richards submission, mostly phone number corrections or
         address/contact corrections. - MW ]

   In searching for a source of RT Megapel cards I put a call out over the
   net for RT parts sources and said that I would summarize back to the net.
   Two responses were received, so a personal thank you to Jon Brinkmann and
   Matt Rush. All leads were contacted with the following results:

        Dickens Data Systems      1-800-848-6177
                Don't inventory RT parts, but do have some RT
                add in hardware and software.

        Dickens Technologies      404-418-0630
                Carry all parts.

        Next Generation Systems   313-435-5086
        Contact: Randy Hastings

        Alpine Computer Sales
        P.O. Box 1500
        1052 Hwy 395
        Gardnerville, NV  89410
        [phone]
                Carry all parts.

        International Data Products
        4445 W. 77th St.
        Mpls, MN  55435
        [phone]
                Don't inventory RT parts any longer.

        RGdata Inc.
        975 Jefferson Road
        Rochester, NY  14623
        [phone]
                Carry all parts.
                Contact: Dave Gerritsen

        Dempsey Business Systems
        18377 Beach Blvd., Suite 323
        Huntington Beach, CA  92648
        [phone]
                Carry all parts, "large quantity".
                Contact: Steve


    We purchased purchased 5 cards and cables from Dave Gerritsen at RGdata.
    Everything arrived OK. We've had good experiences with RGdata in the past,
    I just didn't realize that they carried RT parts.
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

-------------------------
H.7 - What adapter cards are supported in an RT?

      The IBM RT has what is called in the industry a ISA bus.  Based on
      the original IBM PC AT bus in design, the RT has 8 I/O slots in the
      tower (6150 model), and 6 slots in the desktop (6151 model).
      Slot 3 and 6 on the tower model and slot 1 on the desktop models are
      eight bit style slots.  Slot 8 on the tower and slot 5 on the desktop
      model are wired slightly different than standard.

      Technically, any adapter that conforms to ISA standards would work
      provided there are appropiate device drivers AND no conflicts with
      existing adapters registers and bus addresses.

      The RT diagnostics program disks are unfortunately rather particular
      about OEM cards that emulate IBM adapters.  This can sometimes lead
      to problems running diagnostics, where the system will otherwise run
      fine with the regular operation system.

      NOTE: See the OS dependent FAQ list for additional hardware that
            may be supported by that operating system.  The information
            and part numbers shown below generally reflect AIX usage.

      Feature code numbers and part numbers, where known, are shown in
      parenthesis like this (#feature,partnum).  Part numbers DO change
      with EC (Error Correction) changes and production run changes.

      [ These numbers should be able to be cross-referenced if no longer
       correct. - MW ]

        Memory cards -
           - For Model 10,15,20,25,and A25.
             * 1Mb Memory Expansion  (#8222,6848223)
             * 2Mb Memory Expansion  (#4739,6299228)
             * 4Mb Memory Expansion  (#3156,61X6157)
           - For Models 115,125 and B25 only
                (for use with RT PC Advanced Processor Board 08F3639 only)
             * 4Mb Fast Memory Expansion  (#7004,61X7005)
             * 8Mb Fast Memory Expansion  (#7008,61X7009)

           - Clearpoint Systems made memory cards for RT systems
             * 8Mb Fast Memory
                [ Need address/phone number of Clearpoint - MW ]

           - Note: The model 130,135 and B35 are at their maximum
             16MB of memory soldered on the processor card.

        Perhiperial adapters -
         * Small Computer System Interface Adapter  (#7000,61X7001)
           - Fuse 1.0A 250V  (0855253)

        Fixed Disk adapters -
         * PC AT Fixed Disk and Diskette Drive Adapter  (#3428,79X3431)
         * ESDI Magnetic Media Adapter  (#6341,00F2160)
         * RT PC Extended ESDI Magnetic Media Adapter  (#????,08F3766)
         * RT PC Portable ESDI Magnetic Media Adapter  (#3506,08F3506)
           (usable only in models 115/130/125/135/B25/B35)

        Tape Drive adapter -
         * RT PC Streaming Tape Drive Adapter  (#4797,6299222)

        Display Adapters -
         * IBM Monochrome Display and Printer Adapter (#4900,8529148)
         * IBM PC Enhanced Graphics Adapter [EGA] (8654215)
           - IBM PC Graphics Memory Expansion Card (6323468)
           - 640 x 350 pixels,  16 colors, with color display.
           - 640 x 350 pixels,  16 grey level with monochrome display.
         * RT PC Advanced Monochrome Graphics Display Adapter (00F2357)
           - 720 x 512 pixels,   2 colors
         * RT PC Extended Monochrome Graphics Display Adapter (6299351)
           - 1024 x 768 pixels,  2 colors
         * RT PC Advanced Color Graphics Display Adapter (00F2350)
           - 720 x 512 pixels,  16 colors from palette of 64 colors.
         * Megapel Display Adapter (#7658)
           - has two boards fastened together
             - Display Controller (6247666 or 6247529)
             - Display Processor  (6247662)
           - 1024 x 1024 pixels,  256 colors from palette of 4096 colors.
                using the 5081 model 16 or 19.
           - 1024 x 1024 pixels    16 grey levels on the 5081 model 11
             monochrome display.

        Communication adapters -
         * RT PC 4-Port Asynchronous RS-232C Adapter (UN-Buffered)
             (#4763,???????)
         * RT PC 4-Port Asynchronous RS-422A Adapter (UN-Buffered)
             (#4764,???????)
         * RT PC 4-Port Asynchronous RS-232C Adapter (Buffered)
             (#1356,61X6339)
         * RT PC 4-Port Asynchronous RS-422A Adapter (Buffered)
             (#1357,79X3782)
         * IBM PC AT Serial/Parallel Adapter (#0215,8286147)
         * IBM PC 3278/79 Emulation Adapter  (long)  (#????,???????)
                 (Early version is long, and only one may be installed,
                  and has no switches to alter memory addresses.)
         * IBM PC Advanced 3278/79 Emulation Adapter  (#5050,8665792)
                 (later version is short, has switches, and a maximum
                  of 4 may be installed.)
         * IBM PC Network Adapter - discontinued 07/88. (#0213,8286171)
         * IBM Token-Ring Network RT PC Adapter (#3797,67X0432) Early version
         * IBM Token-Ring Network RT PC Adapter (#3797,69X8142) Late version
         * RT PC Multiprotocol Adapter (#4762,08F3193)
         * RT PC Baseband Adapter [Ungerman-Bass Ethernet] (#6810,61X6809)
         * 8-Port Asynchronous Mil-Std 188 Adapter (#3169,08F3170)
         * 8-Port Asynchronous RS-232-C Adapter (#3165,08F3166)
         * 8-Port Asynchronous RS-422-A Adapter (#3171,08F3172)

        Special -
         * RT PC Floating-Point Accelerator (#4758,6299220)
           (for use with RT PC Processor board 79X3766 only)
         * Advanced Floating-Point Accelerator [115,125,B25 only]
           Note: There are two versions of this card:
             - level 1 (#6814,61X6814) (bar code A117Kxxxxxx) can be used with
               either the original processor board (P/N 79X3766), or the
                   Advanced Processor board (P/N 08F3639).
             - level 2 (#6815,08F3589) (bar code A1206xxxxxx)
               use with RT PC Processor Board 79X3766, or
               RT PC Advanced Processor Board 08F3639, or
               RT PC Enhanced Advanced Processor Board 08F3587.
         * Enhanced Advanced Floating-Point Accelerator [130,135,B35 only]
                (#6815,???????) [is this the level 2 board? - MW]
         * Personal Computer AT Coprocessor Card (#4756,6299226)
           - AT Math processor chip [80287], (#0211,8286127)
         * 5080 Peripheral Adapter (#7561,6487562)
           - used to attach the 5085 dials feature and the 5085 Lighted
             Program Function Keyboard feature.
             Identifyable by the three 10-pin MODU connectors
         * 5080 Attachment Adapter (#7860,6247851)
           - used to attach the RT processor to the 5085 Graphics processor.
         * 5086 Model 1 Attachment Adapter (#7876,???????)
         * S/370 Host Interface Adapter (#7893,6247891)
           - used to connect the RT processor to the IBM 5088 graphics
             controller.
         * Expansion unit adapter (#3540,08F3727)
           - used to attach the RT PC 6192 expansion unit.
         * IBM Personal Pageprinter adapter RT edition (#2400, 06F2400)
           [No longer available as of September 6, 1989]
           - Provides the capability to attach an IBM  4216-020 printer,
             and is the postscript engine for the printer.
           - Occupies two adjoining slots.
           - Requires the RT Pageprinter Software package to operate.

-------------------------
H.8 - What IBM perhiperials were available?

    There may be other devices supported by other operating systems.
    Refer to the one of the OS specific FAQ lists for more information.
    The following IBM peripheral devices were officially supported by
    IBM for use on the 6150 and 6151:
        [ Feature code numbers and part numbers, where known, are shown
          in parenthies like this (#feature,partnum) - MW ]

    Storage Devices -
      Floppies:
        *   IBM PC AT High-Capacity Diskette Drive (68X3752)
        *   IBM PC AT Dual-Sided Diskette Drive (68X3753)
      Fixed Disk drives -
        *  40Mb Fixed Disk Drive [ R40 ] (#4735,6299235)
        *  70Mb Fixed Disk Drive [ R70 ] (#6941,61X6942)
        *  70Mb Extended ESDI Fixed Disk Drive [ E70 ] (#3988,79X3989)
        * 114Mb Extended ESDI Fixed Disk Drive [ E114 ]
            (#3272,00F2272 or 00F2273)
        * 310Mb Extended ESDI Fixed Disk Drive [ E310 ] (#3310,08F3358)
        * 310Mb Extended ESDI Fixed Disk Drive [ H310 ] (#3310,08F3358)
              [ this drive is really a Maxtor XT-4380E, with a minor
                modification for what Maxtor calls a 'short index pulse' ]

        * IBM 9332 DASD Models 240, 250, 440, and 450
        * IBM 9309 Rack Enclosure Models 1 and 2

        * IBM 6156-1 Portable Disk drive enclosure (1 drive bay).
          - No longer available new as of Sept 15, 1993.
        * IBM 6156-3 Portable Disk drive enclosure (3 drive bays).
          - No longer available new as of Sept 15, 1993.

      Tape Devices -
        * IBM 6157-001 Streaming Tape Drive (QIC 24)
        * IBM 6157-002 Streaming Tape Drive (QIC 150)

    Displays -
        * IBM 5151 Personal Computer Display [PC XT monochrome display]
            (8529171 - low voltage 120VAC)
            (8529209 - high voltage - 220VAC )
        * IBM 5154 Personal Computer Enhanced Color Display [ EGA ]
            (6321035 - model 1 low voltage)
            (6321049 - model 2 high voltage Northern Hemisphere)
            (6321036 - model 3 high voltage Southern Hemisphere)
        * IBM PC Display Stand (#????) (for EGA display)
        * IBM 5081 Display Models 11, 12, 16, and 19
        * IBM 6153 Advanced Monochrome Graphics Display
          - No longer available new as of Sept 15, 1993.
            (6299240 - 120VAC 50/60 Hz.)
            (6299241 - 220VAC 50/60 Hz.)
        * IBM 6154 Advanced Color Graphics Display
          - No longer available new as of Sept 15, 1993.
            (6848113 - 120VAC 50/60 Hz. group 1)
            (6848114 - 120VAC 50/60 Hz. group 2)
            (6848115 - 120VAC 50/60 Hz. group 3)
            (6848116 - 220VAC 50/60 Hz. group 1)
            (6848117 - 220VAC 50/60 Hz. group 2)
            (6848118 - 220VAC 50/60 Hz. group 3)
            (6848119 - 220VAC 50/60 Hz. group 4)
           [ what do the group numbers mean?  Power connector style? - MW ]
        * IBM 6155 Extended Monochrome Graphics Display
          - No longer available new as of Sept 15, 1993.
            (6848215 - 120VAC 50/60 Hz.)
            (6848216 - 220VAC 50/60 Hz.)
        * MONITERM monitor VY-6155.  19 inch Black and White display.
            - attaches via the Extended Monochrome Graphics adapter.
          [ Moniterm Corp.'s address and information needed. - MW ]

    Pointing devices -
        *  IBM 5083 Tablet Models 11 and 12 (NO LONGER AVAILABLE)
        *  IBM 5083 Model 11A tablet. (6248516)
        *  IBM 5083 Model 12A tablet. (6248515)
        *  IBM Mouse (#8426,00F2384)  Also called a 6100 pointing device.

    Special devices -
        *  IBM 5085 Lighted Program Function Keyboard (#4710,6246899)
        *  IBM 5085 Dials (#8710,6248436)
        *  IBM 5085 Graphic display system.
        *  IBM 5082 Color Projector Model 1
        *  IBM 5087 Screen Printer

    Printers -
        *  IBM 3852 Model 2 Color JetPrinter
        *  IBM 4202 Proprinter XL
        *  IBM 5842 Modem
        *  IBM 6184 Color Plotter
        *  IBM Pageprinter (3812).
           (Requires special RT font diskette, #3065 on 3812.)
        *  IBM Pageprinter 4216 model 020
           (Requires special RT Adapter and Pagepritner software for attachment)
        *  IBM Pageprinter 4216 model 030
           (Attaches via standard serial or parallel port)
        *  IBM 5201 QUIETWRITER Printer, Models 1 and 2
           (Model 2 supported in character mode and 5152 compatible
            graphics mode only).
        *  IBM 4201 Proprinter
        *  IBM 5152 Graphics Printer (NO LONGER AVAILABLE)
        *  IBM 5182 Color Printer (NO LONGER AVAILABLE)
        *  IBM 6180 Color Plotter Model 1
        *  IBM 7371 Color Plotter
        *  IBM 7372 Color Plotter
        *  IBM 7374 Color Plotter
        *  IBM 7375 Color Plotter Model 1 and 2
        *  IBM PC Printer Stand (#5614)

    ASCII Terminal devices -
        * IBM 3151 and IBM 3161 ASCII Display Station
        * IBM 3162 and IBM 3163 (in 3161 mode).
        * ASCII terminals that adhere to ANSI 3.64 protocol as implemented
           by DEC VT100 and DEC VT220 (tm) or equivalent.
           VT-100 and VT-220 are Registered Trademarks of Digital
           Equipment Corporation.

-------------------------
H.9 - What cables are available?

      Feature codes, where known are listed like this (#xxxx).

      Part Num  Description
      ========  ====================================================
      61X6937   Cable, fixed-disk and diskette drive positions A-D
      79X3777   Cable, fixed-disk and diskette drive positions A-E
      6298359   Cable, power distribution.
      6450217   PC AT Communications Cable (#0217)
                (3 Meters 9-pin to 25 pin)
      6450242   IBM PC AT Serial Adapter Connector Cable (#0242)
                (10-inch  DB 9-pin to 25 pin)
      79X3914   RS232 Terminal attach cable. (#????)
                (3 meters 10-pin MODU to DB25 pin MALE
                 use with 8-port, 4-port or native serial ports)
      6298526   RS232 Terminal attach cable. (#3913)
                (3 meters 10-pin MODU to DB25 pin FEMALE
                 use with 8-port, 4-port or native serial ports)
      6298525   RS232 Serial Printer attach cable.
                (3 meters 10-pin MODU to DB25 pin FEMALE
                 use with 8-port, 4-port or native serial ports)
      6294704   RS232 Modem attach cable.
                (3 meters 10-pin MODU to DB25 pin MALE
                 use with 8-port, 4-port or native serial ports)
      1525612   IBM PC Printer Cable (#5612)
      79X3468   SCSI interface card to device cable (#3468) (8 Meters)
      79X3470   SCSI device to device cable (#3470) (1 Meter)
      6294812   Modem Cable RS232C for Multi-Protocol adapter
                ( 3 meters 16 Pin MODU to DB25 male )
      6294814   Autocall Cable RS366 for Multi-Protocol adapter
                ( 3 meters 16 Pin MODU to DB25 male )
      6294816   Modem Cable X.21 for Multi-Protocol adapter
                ( 3 meters 16 Pin MODU to 15 pin male )
      08F3157   8-Port RS232C Fan-out cable assembly (#3157)
                ( 6 foot cable to fanout box with 8 10-pin MODU connectors)
                (also used with MIL-188 adapter)
      08F3158   8-Port RS422A Fan-out cable assembly (#3158)
                ( 6 foot cable to fanout box with 8 6-pin MODU connectors]
      6487586   RT PC 5083 Tablet cable kit. (#7586)
                - used only to attach a model 1 or 2 tablet to an RT.
                  not needed for 11A or 12A tablets.
      6487563   RT PC 5080 Peripheral Adapter cable kit
      6247861   RT PC 5080 Attachment cable kit. (#7861)
                Includes two cables, terminator, diskettes and documentation.
      22F9207   RT PC Expansion unit cable, 2m.

-------------------------
H.10 - What is the pinout of the 6150 serial ports?
       How do I make my own RS232 cables compatible for use with AIX?

    The funny connector on the back of the 6150 labeled 'S1' and 'S2'
    are the native serial ports built into the system planar board
    of the 6150 tower models of the RT.  This connector is refered
    to in the IBM hardware manuals as a MODU connector.

    The 10-pin connector used on the native serial ports, is also used by
    the fan-out box for the RT RS232 8-port card.  These part numbers
    for the connector were given to me by the IBM support center in
    Austin, TX for the RiscSystem/6000.  The 6000 has the same 10 pin
    MODU connectors for the 6000 systems native serial ports, and is the
    same connnector used by the RT systems native serial ports.

                AMP Product Corp.

                  Housing       AMP P/N         102394-3
                  Cover         AMP P/N         102541-3
                  Back Cover    AMP P/N         102536-3
                  Ferrule       AMP P/N         102903-3
                  Receptacle    AMP P/N         2-87195-0
                  Receptacle    AMP P/N         86491-4
                  Shield Kit    AMP P/N         103125-2

   You can also get a 10-pin MODU connector pre-wired to a DB 25 pin
   male connector, used for the Risc/System 6000 and is a short stub
   about 4 inches long.  It is IBM P/N  00G0943.  This stubby cable
   will work just fine for connecting modems, and with a properly wired
   extension able, for printers and terminals as well.

   ======================================================================
    Looking INTO the connector pins in the back of the RT tower,
    here is the pin-out assignments and functions.  The connector on the
    back of the RT tower model is a male MODU connector.  This pinout
    is the same for the IBM 4-port card, and the fan out box of the IBM
    8-port card.

                               @   pin  abb   function
    +-----------------+        T    1   TX  = Transmited data from RT
    |                 |        T    2   DTR = Data Terminal Ready
    |  1  2  3  4  5  |        T    3   RTS = Ready to send
     |               |         R    4   RI  = Ring Indicate
     | 6  7  8  9 10 |         -    5   -     No connection
     |               |         R    6   RX  = Received data to RT
     +---------------+         R    7   DSR = Data Set Ready
                               R    8   CTS = Clear to send
                               R    9   CD  = Carrier Detect
                               -   10   GND = Signal Ground

       @ means   T = RT transmits  R = RT receives (listens)

   ======================================================================
   RS232 Modem attach cable. Feature #4704, Part# 6298240  Option #6294704
         IBM supplied cable is 3 meters long, with a 25 pin male connector.

   This has worked for my modem attach.. I have not actually used a meter
   on a STOCK IBM RT modem cable, but this works for me.

   NOTE: Metering the IBM RS6000 stubby cable P/N 00G0943 matches this pinout.

     Pin#   1   2  3   4  5  6  7  8  9  10      10-PIN MODU  female
            |   |  |   |  |  |  |  |  |  |
            |   |  |   |     |  |  |  |  +--+
            |   |  |   |     |  |  |  |  |  |
            2  20  4  22     3  6  5  8  7  1    DB25 male connector

       NOTE: pin 5 of the MODU connector is unused.

   ======================================================================
   The following cable wirings were discovered by using a meter probe on
   IBM RT RS232 cables and by opening the hoods on the DB25 connector ends.
   IBM part numbers and option numbers listed where known.
   They are still orderable from IBM the last time I checked.

   ======================================================================
   RS232 Terminal attach cable. Feature #3913  Part# 6298526  Option# 6298186

     Pin#  10     6   1     9   2  8   3   7   10-PIN MODU female
            |     |   |     |   |  |   |   |
            |     |   |     |   |  +---+   |
            +--+  |   |  +--+   |  |       |
            |  |  |   |  |  |   |  |       |
     Pin#   1  7  2   3  4  5   6  8       20   DB25 Female connector

   ======================================================================
   RS232 Serial Printer attach cable.
         Feature #4803  Part# 6298525 Option# 6294803

     Pin#  10      6   1   7  9  3  2      8     10-PIN MODU female
            |      |   |   |  |  |  |      |
            |      |   |   |  +--+  |      |
            +--+   |   |   |  |     +--+   |
            |  |   |   |   |  |     |  |   |
     Pin#   1  7   2   3   4  5     6  8   20    DB25 female connector

-------------------------
H.11 - What is the pinout of the 6150/6151 Mouse/Tablet port?

   [ Has anybody gotten a NON-IBM RT mouse running on an RT? - MW ]

     Here is pin-out and information on the RT locator port.
     More information is available from "IBM RT PC Hardware Technical
     Reference" Volume 1 P/N 75X2032,  Chapter 9  pages 9-24 thru 9-29,
     and from Chapter 5, pages 5-131 thru 5-135 and page 5-145.

    [ The connector is a AMP type, I don't have the P/N of how to get the
     parts to construct one - MW ]

        Connector Specifications:
        (view is looking into the connector (male receptacle) socket on the
         back of the RT system unit.

         +--------------+            1 = ground.
         |    1  3  5   |            2 = Transmit to device.
         |              |            3 = +12 Volts
          -   2  4  6  -             4 = -12 Volts
           |          |              5 =  +5 Volts
           +----------+              6 = Receive from device.

    The RT standard locator device is a two button mouse.
    The middle button on a three button mouse can be simulated by
    pressing both buttons simultaniously, mostly used for X-windows.

      Resolution: 25, 50, 100 or 200 counts per inch.  Default=100.
      Sampling rate: Programmable 10,20,40,60,80 or 100.  Default=100.
      Data modes:  Stream (default), remote.
      Scaling: Linear (default), exponential.
      Protocol: RS232C, 9600 baud, async, full duplex,
         1 stop bit, odd parity.

      - Self test at power-on or when requested by system.
      - The locator device is semi-intelligent and has 14 different
        commands that it understands.
      - 11 bit framing protocol.

    IBM part numbers for the RT mouse are:

      00F2384   Mouse.  Also called a 6100 pointing device.

    A IBM 5083 tablet may also be used as a locator device.

    IBM part numbers for the 5083 tablet are:

      6248516   IBM 5083 Model 11A tablet.
      6248515   IBM 5083 Model 12A tablet.
      6248522   Stylus for 11A or 12A tablet.
      6248523   4-Button Cursor for 11A or 12A tablet.
      6248524   Cable RT PC to 5083 for 11A or 12A tablet.

-------------------------
H.12 - What is the pinout of the 6150/6151 Keyboard port?

     Here is pin-out and information on an RT keyboard.
     More information is available from "IBM RT PC Hardware Technical
     Reference" Volume 1 P/N 75X2032,  Chapter 9  pages 9-3 thru 9-23,
     and from Chapter 5, pages 5-85 thru 5-114.

    [ The connector is a AMP type, I don't yet have the P/N of how to get
      the parts to construct one. Anybody?  - MW ]

     Connector Specifications:
        (view is looking INTO the female connector socket on the cable attached
         to the keyboard)

         +--------------+            1 = +5 Volts
         |    5  3  1   |            2 = Keyboard Data
         |              |            3 = Speaker Signal
          -   6  4  2  -             4 = Speaker Return (+5V)
           |          |              5 = Ground
           +----------+              6 = Clock  (diagrams in the book seem
                                         to indicate that clock is generated
                                         BY the keyboard)

    Microcomputer in keyboard performs following functions:
      - Self test at power-on or when requested by system.
      - keyboard scanning.
      - Buffering of up to four key scan codes.
      - Executing the hand-shake protocol requred by each scan code transfer.
        - full-duplex serial interface
      - communicates with a 8255A PIO chip and a 8501 microprocessor
        in the RT planar.
      - 11 bit framing protocol.

    IBM part numbers for the RT keyboard are:

      1392366   Keyboard, United States English.
      1392374   Keyboard, United Kingdom English.
      1392373   Keyboard, Canadian-French.

    Ten other part numbers are listed for other language layout keyboards.

-------------------------
H.13 - Can I use an AT keyboard on an RT?

       NO.  While most of the signals are the same, there are four
       major differences:
           1) There is a speaker in the keyboard.
           2) The physical connector is not the same.
           3) Some of the scan codes are different.
           4) Some of the programing commands are not implemented in
              the AT keyboard.

     Difference 1 and 2 are managable, but 3 and 4 imply some way
     is needed to alter the keyboard ROM chips, or basic hardware.

    [ ANY input on how to hack a keyboard for RT compatibility is
      gladly welcomed!  - MW ]

-------------------------
H.14  How do I get a parallel printer attached to an RT?

      [ This information has been taken from the AIX manuals, if there
        is a difference for AOS, let me know. - MW ]

      There are three different ways to attach a centronics parallel
      printer to the RT.
      A maximum of two parallel printer interfaces are supported, but
      only by using a AT serial/Parallel card, jumpered at the
      secondary printer port address.

        1) AT Serial/Parallel interface card.
           Parallel port primary address = 3BC
           Parallel port secondary address = 278

        2) PC/XT Monochrome/Parallel printer card.
           Parallel port only address = 3BC
           No jumper available to disable this port.

        3) Megapel card has a parallel interface on it.
           Parallel port only address = 3BC
           Swich 1 position 2 enables/disables the port.
           Shipped disabled from factory.

        Recent discussions in this newsgroup indicate that clone printer
        port cards will work with AIX.  Personally, I have used both
        the AT Serial/Parallel card and the XT monochrome adapter just
        fine to run parallel printers.

-------------------------
H.15  What are the switches on the Megapel adpater for?
      Technicial information on Megapel adapter and display.

      Switch 1 is located on the display processor card (the one with the
      25-pin parallel printer connector on it).

          1   Not used. Must be set to OFF.
          2   On = Enable printer port.   Off = Disable printer port.
          3   Enable CGA emulation mode.  Off = Normal Megapel mode.
          4   Not used. Must be set to ON.

      [ Anybody know what the 'not used' switches do? - MW ]

     Megapel and display technicial information:
        Slot position           Must be installed in slots 4 and 5 ONLY.
        I/O Addresses           0930-094F
        Memory ddresses:        0B8000-0BBFFF   CGA emulation mode.
                                C00000-C3FFFF   Adapter data space.
                                D60000-D7FFFF   Adapter program space.
        DMA channel             7
        Interrupt level         11  (shared)
        Horizontal Frequency    63.36 Khz
        Vertical Frequency      60 Hz,  Non-Interlaced.
        Display connector       3-pin Video (D-shell)

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: [e-mail] (Pim Zandbergen)
   Date: 24 Oct 93 21:20:48 GMT

   The original Megapel RAMDAC is the Brooktree BT 451 KG 110.
   It does 4 bits per color, yielding a color palette of 4096 colors.

   You can replace it with a BT 458 KG 110 (or the BT 458 KG 135).
   There's a #define in the Megapel X server sources which
   defines the number of bits per color. With the BT 458 you will
   have a color palette of 16M colors.

   I tried to order one, unsuccessfully. The Dutch Brooktree dealer
   wouldn't sell me RAMDACS in quantity one, and Brooktree did not want
   to deal with me directly.
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

   This DAC replacement was a IBM RPQ (Request for Price Quotation)
   feature for the Megapel card, and did upgrate the color palette to
   16 Million colors.
       If ordered at ship time:  RPQ 8A0158
       for field upgrade:        RPQ 8A0159

-------------------------
H.16 - AT Co-Processor information.

        [ Watch this space for more details! - MW ]

        o   IBM PC AT Math Coprocessor (#0211)
        o   IBM PC AT 512Kb Memory Expansion Option (#0203)

-------------------------
H.17 - How can I get the maximum data on a 6157 tape drive?

  [ While the 6157 hardware is the same, and the type of tape used
    is the same, the default values for the tar command for AOS may
    be different than AIX. - MW]

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: [e-mail] (David L. Crow)
              IBM Advanced Workstations Division
   Date: 30 Apr 92 14:12:59 GMT

  >We have the 6157-002 model (150Meg, I think) and for some
  >reason, it needs three tapes to backup only 240Meg of data.

    DC 600A tapes should hold 118 MB of data.  Of course this is somewhat
  dependent on the RT systems ability to keep the data moving to the tape
  as it is streaming.  If there is a break in data bacause the backup command
  can't get it there quick enough, then you'll lose some of your capacity.
  Here is an item from ASKQ two or three years ago that describes what
  flags to use to make sure that you get the maximum capacity out of your
  6157.  This probably could go into the FAQ (except the FAQ is pretty
  much just for AIX Version 3).

  ============================================
  Subject: 6157 TAPE INFORMATION FOR AIX BACKUP COMMAND

  The correct descriptions for the -s and -d flags of the AIX backup
  command are:

   -slength

      Specifies the length of the usable space on a tape medium. This is a
      combination of the physical length and the number of tracks on the
      tape. The default "length" is 2700.

      To get the value for "length", you should multiply the physical
      length of the tape by the number of tracks (see table below).

  -ddensity

      Specifies the amount of data a system can write to a tape medium in
      bytes per inch. The default "density" is 700 bytes per inch.

      The density written to the tape is hardware controlled and can not
      be changed. The 6157-001 writes at 10,000 ftpi (flux transactions
      per inch) which is approximately equivalent to a density rating of
      8,000 bits per inch. The 6157-002 writes at 12,500 ftpi which is
      equivalent to a density rating of 10,000 bits per inch.

      The -d (density) parameter is used with 0.5 inch tape drives to
      specify the density, such as 800, 1600, or 6250 bpi, but doesn't
      affect the density, that is, bits per inch, of the 6157.

      The -d parameter is used for the 6157 in the calculation of what
      quantity of data will be put on the tape. To increase the amount of
      data on the tape, the value for -d should be 1000 for 6157-001 or
      1200 for 6157-002.

  Reference: AIX/RT Commands Reference Volume 1, SC23-2011-1, page 91.
             AIX PS/2 Commands Reference, SC23-2025, page 35.

  CALCULATION OF TAPE CAPACITY:

      The following formula yields the approximate capacity of a tape:

      # tracks * length * 11 inches * density = capacity (in bytes).

       9 * 300 * 11 * 1000 =  29,700,000 bytes or about 29 MB
      18 * 600 * 11 * 1200 = 142,560,000 bytes or about 142 MB

      The "11 inches" is the length of the recording foot, the actual
      amount of data stored on the tape per foot, and the interblock gaps
      take up approximately 1 inch per foot.

  TABLE:

  For the following AIX command(s), the values for -s and -d are in the
  table below:

       find ./ -print | backup -iv -C2000 -f/dev/rmt0 -sXXXX -dYYYY

   Recommendations for 6157-001:

   TAPE CARTRIDGE LENGTH    TRACKS   -s    -d   CAPACITY

   3M DC 300A     300 feet     9    2700  1000    29 MB
   3M DC 300XLP   450 feet     9    4050  1000    44 MB
   3M DC 600A     600 feet     9    5400  1000    59 MB

   Recommendations for 6157-002:

   TAPE CARTRIDGE LENGTH    TRACKS   -s    -d   CAPACITY

   3M DC 600A     600 feet    15    9000  1200   118 MB
   3M DC 600XTD   600 feet    18   10800  1200   142 MB
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

-------------------------
H.18 - What Non-IBM hard disks can be used in an RT?

      [ This section may need to be refined, as AOS hackers may
        have introduced other disk interface cards to its support.
        Anybody with other NON-IBM drives running in your RT, using
        AIX or AOS let me know how you achived this, and what steps are
        necessary to make this work. - MW]

        The RT uses two different type of drives in the internal
        drive bays, ST-506 MFM and ESDI.

        There were FOUR different disk controller cards used by
        IBM in 6150 and 6151 systems.

           - The IBM PC AT FLoppy/Hard disk adapter,
                * Will run two floppies, 1.2 Meg or 360 Kb.
                * Two ST-506 MFM 40 Meg hard drives.
                * Used with the R40 series drives.
                * Used in the original IBM PC/AT.
                * Normally only found on the earlier RT machines.
                  It will work on all model RT systems.

                NOTE:   A second controller can be added into slot two if
                  jumpered as a secondary controller. However, AIX for the
                  RT will only be able to access one of the two possible
                  connections on a controller jumpered for secondary
                  operations, for a total of three drives.

           - The ESDI disk controller.
                * Will run two floppies, 1.2 Meg or 360 Kb.
                * Two ESDI 70 Meg or 114 Meg hard drives.
                * Normally only found on the 115 and 125 RT machines.

                NOTE:   A second controller can be added into slot two if
                  jumpered as a secondary controller. However, AIX for the
                  RT will only be able to access one of the two possible
                  connections on a controller jumpered for secondary
                  operations, for a total of three drives.

           * NOTE2: Both of the above controllers can be run in any
             combination for a maximum of two controllers and three drives.

           - The Extended ESDI (or EESDI) disk controller.

                * Will run two floppies, 1.2 Meg or 360 Kb.
                * THREE ESDI 70 Meg, 114 Meg, or 310 Meg hard drives.
                * Normally used on later model 125 RT machines and
                  exclusively on the 135 model machines.

           - The Ported Extended ESDI (or EESDI) disk controller.

                * Will run two floppies, 1.2 Meg or 360 Kb, but only
                  when jumpered as a primary controller.
                * THREE ESDI 70 Meg, 114 Meg, or 310 Meg hard drives.
                * Intended use was for running an additional three ESDI
                  drives in a 6156 Portable Disk enclosure, with up to
                  three removable hard drives.
                * Can function as the primary controller, but factory
                  default jumpers place this as a secondary controller.
                  With this controller, an RT could have SIX ESDI drives.
                * Supposedly has a faster transfer rate chip, but it
                  not documented as such.

        NOTE3: On all of the above controllers when jumpered for secondary
          operations, the floppy drive function of that controller is
          inaccessble by AIX, not sure about AOS.

        The MFM and ESDI adapters in the RT were made for IBM
        by Western Digital.  The EESDI adapter appears to have been
        made by IBM, it has IBM PROMs and PAL devices on its board.

        The EESDI adapters are very SENSITIVE to timing problems with
        some OEM drives.

     *  The IBM H310 drive was a relabeled MAXTOR XT-4380E drive.
        I personally have had success only when a specific TLA number
        controller board is installed on the drive, with what MAXTOR
        calls 'a short index pulse'.

     *  Drives known to work with the EESDI controller have the following
        ientification numbers:

        MAXTOR XT-4380E  Series: 2
            TLA: 1094508-2   HDA: 1014294   PCBA: 1018528_A

        MINISCRIBE: Model 9380E
             9380EF
             HDA: 01P4  PCBA: 04P1 BDMT: 05P1 Unique: 02P2
             TDA: 3077A 3041A

        PIRAM: Model # ID337-RT-H2
            Barcode says: model #638 AWE 00015432
             PCB: 201384  EC: 11665 CCL A

       [ Watch this space for more JUMPER details.
         Also.. anybody with experiences with OTHER vendor drives running
         on an RT with AIX or AOS would be welcome. - MW ]

     *  The E70 and E114 hard drives use a 150 Ohm inline resistor.
        It has pin one as the common pin, and has 12 total leads.
        This is NOT documented ANYWHERE that I could find!

     * Switch settings for E70 and E114 hard drives.
       For RT installation, the switches must be as follows:

                  1  2  3  4  5  6
                +------------------+
           On   |    X  X     X    |
           Off  | X        X     X |
                +------------------+

       - Eliot  <[e-mail]>
         reports that the switch meanings are:

                switch
                1:      on  = pwr up via software (factory default)
                        off = pwr up with system
                2:      on  = diags (factory default)
                        off = ?
                        [ My guess.. since on is the RT normal position,
                          then off must activate diagnostic mode. - MW]
                3:      on  = 512 byte sectors (factory default)
                        off = 256 byte sectors
                4,5,6:  drive select in binary
                        i.e. 4 off 5 on 6 off = drive select 2

     * Switch settings for E310 hard drive ONLY.
       For RT installation, the switches must be as follows:

                  1  2  3  4  5  6  7
                +---------------------+
           On   | X     X  X  X  X    |
           Off  |    X              X |
                +---------------------+

        [ Anybody know the meanings of the switches for the E310 drive? - MW ]

-------------------------
H.19 - What is the difference between an R70 and an E70 drive?

     Both drives are physically identical 'IBM type 0667' hard drives.
     The difference is in the formatting, and coupled with the
     Extended ESDI Magnetic Media Adapter. This adapter also employs the
     RT PCs burst DMA I/O capability and incorporates a more efficient
     alternate-sector scheme than the previous ESDI adapter.

        The R70 drive has a 4:1 interleave.
        The E70 drive has a 1:1 interleave.

     There is however, a discrecpency between the reported number of cylinders
     between the different versions, and the VRM utility.
     [ Anybody know which is correct? - MW ]

-------------------------
H.20 - What are the characteristics of the various IBM RT disk drives?

       This table is collected from the various hardware manuals
       for the IBM RT, and from other sources.

        Note: All drives have a 512 byte sector size.

        Drive   part#           type    Cyl     head    Sects intrl (2)
        R40     6299235         MFM     733     7       17      2
   (1)  R70     61X6942         ESDI    566     7       36      4
        E70     73X3989         ESDI    582     7       36      1
        E114    00F2273         ESDI    914     7       36      1
        E310    08F3358         ESDI    1225    15      34      1
   (3)  H310    08F3358         ESDI    1225    15      34      1

  Note 1: I am not sure why the tech manuals give such radically
          different number of available cylinders for the identical
          disk drive.  I have seen an R70 and E70 side by side, and
          they are identical, and are 'IBM type 0667' drives!
          [ Are there some other 'R70' drives out there?? -MW ]

  Note 2: intrl = Sector interleave value,  sects = Sectors per track.

  Note 3: The MAXTOR documentation indicates that the drive normally
              has 36 sectors per track, yet all the IBM drive tables and
              documentation indicate differently.
              See also the VRM table below.

        An intresting recent addition is this table I built by examining the
        VRM utility format program. When you need to reformat a new or
        non-IBM drive, this utility will place the minidisk partition table
        and other IBM required identification information on the drive.
        While you can enter non-standard paramenters, built into the
        program are the parameters for all the IBM drives.
        Anybody know the reason for the discrepency?  Which is correct?
        The R30 is intresting, I have never seen it described in any
        IBM liturature for the RT.

        Drive   type    cyls    heads   sects   intrl   skew    precomp
        R30     MFM?     733     5      17      2       0       300
        R44     MFM      733     7      17      2       0       300
        R70     ESDI     566     7      36      4       0       none
        E70     ESDI     683     7      35      1       0       none
        E114    ESDI     915     7      35      1       7       none
        E310    ESDI    1225    15      33      1       8       none
   (3)  H310    ESDI    1189    15      34      1       0       none

-------------------------
H.21 - What SCSI devices can be attached?

     The amount and type of support for SCSI devices varies by the
     operating system used. Please refer to the different RT operating
     system specific FAQ list for more information about SCSI support.

     The IBM suported SCSI adapter is a 'Differential Driver/Receiver
     option' with the 'Alternative 2 connector'.  The SCSI interface
     conforms to (then) proposed ANSI standard X3T9.2/82-2 Rev. 17B.

     Two wires are used for each signal lead in a push-pull signaling
     method also called 'differential-ended'.  Most drives for other vendor
     workstations and PCs use a 'single-ended' SCSI implementation.
     What this boils down to is that the IBM SCSI card is electriclly
     incompatible with a lot of the off-the-shelf SCSI drives.

     IBM officially supported only one device attached to the SCSI
     interface card, the 9332 'Athens' disk drive.

     However, all is not lost. :-)
     Some vendors do offer their SCSI drives with an optional differential
     interface.  There also exist a couple of manufacturers of
     'Differential-to-single-ended' converter boxes.  These boxes allow
     a bi-directional conversion of the SCSI bus and will allow attachment
     of these single ended disk drives.

     See the AIX FAQ for more information about using OEM SCSI disks
     on an RT using the IBM SCSI board.

     Under the AOS operating system, several people have modified the
     system to use an Adaptec SCSI controller.  That controller uses
     single-ended devices.

        [ More information about this Adaptec controller can be found in
          the AOS specific FAQ list. - MW ]

-------------------------
H.22 - What do the LED codes mean during power on?

     When power is first applied, initial self tests are performed by
     built it ROM routines and special processor on the system planar
     board.  These self tests should complete with in 1-2 minutes.

        ROS LED Values during IPL
        00      Initialization of Mono/Printer adapter failed
        01      ROS CRC did not compare - Fatal
        02      Soft IPL check failed - Fatal
        03      Memory error or no memory - Fatal
        04      Processor card logic error - Fatal
        05      Processor or memory error condition - Fatal
        07      IOCC test resident POST - Fatal
        08      Bad processor card in IOCC test - Fatal
        09      Keyboard adapter resident POST - Fatal
        0c      initialization failed - Mono/Printer adapter and APC
        10      System timer resident POST - Fatal
        11      Interrupt controller POST - Fatal
        12      DMA arbiter resident POST - Fatal
        13      Serial port resident POST
        14      Fixed disk resident POST adapter 1 test
        15      Fixed disk resident POST adapter 2 test
        16      Diskette resident POST adapter 1 test
        17      Diskette resident POST adapter 2 test
        18      Extension ROS
        19      Attemting Manufacturing IPL
        1c      Advanced Processor card - Fatal
        1u      Enhanced Advanced Processor and memory Mgmt card - Fatal
        20      NVRAM CRC check
        21      No boot record found (NVRAM selected devices)
        22      No boot record found (ROS selected devices)
        23      Disk or diskette adapter slot or address - Fatal
        25      User error - invalid RamSpecReg - Fatal
        26      Attempting soft IPL
        27      Bootable code exceeds available storage - Fatal
        28      Unexpected return from loaded code - Fatal
        29      IPL process passed control to loaded code.
        3c      Advanced Processor card and first 128K of memory.
        3u      Enhanced Advanced Processor and memory Mgmt card.
        4c      APC logic (Advanced Processor Card).
        4u      Enhanced Advanced Processor and memory Mgmt card Logic.
        5c      APC logic and system memory.
        5u      Memory expansion option or Enhanced Advanecd Processor and
                memory managment card.
        88      reserved - POR or processor check
        89      Unexpected machine or program check - Fatal.
        8c      IOCC test for APC.
        8u      Enhanced Advacned processor and memory managment card.
        96      Memory card 1 resident POST error condition.
        97      Memory card 2 resident POST error condition.
        98      Memory card 1 and 2 resident POST error condition.
        99      KEY locked, locked response.

-------------------------
H.23 - What does LED code xx mean (during runtime)?

     LED codes displayed while running vary greatly depending on the
     operating system used. Please refer to the different RT operating
     system specific FAQ list for more information about these LED
     codes used.

-------------------------
H.24 - What is different about the RT I/O slots.
       What cards will run in slot 8.

   The IBM RT 6150 and 6151 system units use ISA (AT) style I/O slots,
   however slot 5 on the 6151 and slot 8 on the 6150 are unique to the RT.
   Most cards that do not use memory refresh, or DMA channel 7 will
   have no problem with that slot.  Bus timings may be slightly different,
   from an AT, as I/O accesses are not driven by the processor directly,
   but are routed via a special bus processor called the IOCC.

   The 8th slot in the 6150 RT and the 5th slot for the 6150 only
   have three signals different from the normal PC/AT assignments.

     Pin    Standard     CO-proc slot usage    My notes..
     B19    REFRESH      + SPK DRV             (Wire or'd to speaker control)
     D14    DACK 7       - DACK 8              DMA channel is reassigned..
     D15    DRQ 7        + DRQ 8                 .. ditto

   The following cards cannot go in slot 8:
     - AT 512Kb Memory expansion card (no refresh signal available).
     - Baseband adapter (Ethernet, Ungerman-Bass) [Timing?? -MW]
     - SCSI adapter ONLY when it is using DMA channel 7... channel 7 is
       not connected to SLOT 8.

   These cards require special slot placements:
     - EGA adapter only in slot 3 or 6 (6150) or slot 1 (6151).

     - Megapel adapter is a two boards sandwiched together, and can
       only be installed in slots 4 & 5 in a 6150 tower.
       It can also be installed in slots 2 & 3 (prefered), slots 3 & 4,
       or slots 4 & 5 (least prefered) in the 6151.
       [ It has been noted via discussions in this newsgroup that the
        the later X servers will have problems, errors and timing problems
        if the megapel adapter is NOT placed in the prefered slots! -MW ]

     - AT-Coprocessor in installable ONLY in slot 8 of the 6150 tower,
       or in slot 5 of the 6151 desktop.
       (That's why it is called the coprocessor slot!  :-)

     - The PC XT mono/printer adapter, is ONLY supported in slot 3 in
        the 6150 tower, or ONLY in slot 1 in the 6151 desktop.
        [ I'm not sure why this slot 3 restriction is here, what's
          wrong with slot 6?  Timing? - MW ]
        IBM Mono Adapters with Part numbers 1804065, 1804073 or 1501667
        cannot be used according to the parts book that I have seen.
        The options book indicates that those part number mono adapters
        will not operate correctly with an RT.

        I have had reports that clone monochrome cards also may have
        problems running in an RT.  I have not tried them myself.

   Any 8-bit card is better off in slots 3 or 6 (6150) or
     in slot 1 (6151), as those slots are 8-bit only anyway.
     Save a 16-bit slot for a card that needs it.

-------------------------
H.25 - How do I run diagnostics.

       IBM supplied with most RT systems several books, one set of three books
       are maroon in color, and contain setup, install and one book labeled
       "IBM RT PC Problem Determination Guide" (RT PD).  The Problem
       Determination guide is usually composed of two manuals in one
       binder.  IBM manual number SA23-2604, and for those users who
       ordered AIX with their systems, it also contains SA23-2603 titled:
       "IBM RT AIX Operating System Problem Determination Guide".
       This binder also contains three diskettes with maroon labels.
       Volume one of the three diskettes is bootable, and when booted,
       causes it to examine the system hardware, and place a menu of
       diagnostic options on the screen.  Most of the diagnostics are menu
       driven and are self-explanatory.  The RT PD guide will take you thru
       any special procedures if necessary.

       Further problem diagnosis is available in the dark blue book
       with the title "IBM RT PC 6150 System Unit Hardware Maintenance
       and Service"  Manual# SA23-2605 or Part Number  22F9803.
       This book contains problem isolation charts, part numbers,
       installation information and a SRN (Service Request Number) to
       FRU (Field Replaceable Unit) part index.  This book also contains
       a LED fault code to SRN reference, as well as probable failure part
       analysis charts.

-------------------------
H.26 - Serial port cards maximums and limitations.

        *   The internal serial ports of the 6150 tower model RT are
            normally able to run at a maximum of 19.2K bits per second.
            [ AOS users report that this rate is able to be exceeded by
              modifications to the standard AOS kernel. - MW]
        *   The IBM RT 8-Port Adapter is capable of all 8 ports operating
            concurrently at 19.2 K bits per second.
        *   All 8-Port Adapters installed in a single system unit should
            be set to the SAME interrupt level for best performance.
        *   For proper software operation, 4-Port Asynchronous Adapters
            must be set to a DIFFERENT interrupt level than 8-Port
            Adapters, when installed in the same system unit.
        *   IBM RT 8-port Adapters in the 6192 Expansion Unit should be
            set to DIFFERENT interrupt levels.  Interrupt sharing is not
            supported between the IBM RT System Unit and the 6192
            Expansion Unit.
        *   A maximum of EIGHT 8-port Adapters can be installed on a system.
            (e.g. 6 adapters in the 6192 Expansion Unit and 2 in the RT
             system unit)
        *   Concurrent use of 4-Port Adapters and/or PC AT Serial/Parallel
            Adapters and/or 6150 native Serial Ports with the 8-Port
            Adapters may result in reduced performance on the devices
            attached to the 8-Port adapters, depending upon line speeds
            and device usage.
        *   If a 5080 Peripheral Adapter is installed in the system
            unit, the maximum number of 8-Port Adapters is reduced to four
            for the 6150, and to two for the 6151 System Units.

-------------------------
H.27 - What are the switches on the 3278/79 adpater?

        The 3278/79 emulation adapter short version has one set
        of dip switches in the top left corner.
                SW      Usage
                1        Address range 1  1-ON  2-ON
                2        Address range 2  1-OFF 2-ON
                         Address range 3  1-ON  2-OFF
                         Address range 4  1-OFF 2-OFF
                3        OFF=Disable interrupts, ON=Enable interrupts
                4        reserved
                5        ON for address range 1, OFF for address range 2-4
                6        OFF for slots 1-7 on PCXT and all RT slots.
                         ON  for PCXT slot 8.

-------------------------
H.28 - Jumper location and information on AT Fixed disk adapter.

     The IBM RT PC Fixed disk adapter is a MFM controller, and is stock
     original IBM PC AT controller.  The only drive that IBM used for the
     RT using that controller was the R40. (standard PC-AT 40 MB drive).

     The MFM controller documentation for the RT that I have indicates that
     it can support only TWO of EXACTLY the same type of drive.  The  RT books
     indicate that no matter how the drives are arranged, the MFM controller
     MUST have both drives the same.  The RT docs where quite specific about
     that limitation.  Most likely a limitation of the drvice driver, not the
     hardware.

     If running two controllers make sure that one controller is jumpered
     for PRIMARY controller and is in slot 1.  The secondary controller
     is supposed to be in slot 2, and can run a maximum of one hard disk.
     The floppy interface is not usable on the second controller.
     Secondary addressing is set by placing the jumpers in the position AWAY
     from the metal plate on the card.
     This arrangement was intended to have 2 R40 drives on the primary MFM
     controller and 1 R40 attached to the secondary.

       ----------------------------------------------------- ---
       |                     ::  ::  ::  ::                 ||
       |           o-o .     ::  ::  ::  ::                 ||
       |           o-o .     D   C   ::  ::                 ||
       |           S   P             B   A                  ||
       |                                                    ||
       --------------------------+     +--+            +----+
                                 |_____|  |____________|     |


     Position A is for floppy drive cable.
     B  = for dasiy chained data cable for both hard drives.
     C  = for first drive control cable, or third drive on second card.
     D  = for second drive control cable.
     Jupmers in "S" direction for secondary, "P" for Primary.

     I/O addresses used (jumpered primary, slot 1):
        Floppy drives A and B - 03F0 - 03F7
        Drives C and D        - 01F0 - 01F7

     I/O addresses used (jumpered secondary, slot 2):
        Drives E              - 0170 - 0177

     DMA channel 2 (diskette only)
     IRQ diskette - 6  Fixed disk - 14.

-------------------------
H.29 - Jumper locations and information on ESDI adapter.

    The ESDI controller has the same connector arrangement as the MFM
    controller and only a SINGLE jumper in about the same position as the
    MFM controller.  Looking at the card, the jumpers would be with the "S"
    direction being for Primary (backwards from the jumpering for the MFM
    controller) and the "P" direction for secondary.
    This interface board was discontinued with the announcement of the
    EESDI controller card.

    This controller has a part number of  00F2160.

     I/O addresses used (jumpered primary, slot 1):
        Floppy drives A and B - 03F0 - 03F7
        Drives C and D        - 01F0 - 01F7

     I/O addresses used (jumpered secondary, slot 2):
        Drives E              - 0170 - 0177

     DMA channel 2 (diskette drives only)
     IRQ diskette = 6  Fixed disk = 14.

-------------------------
H.30 - Jumper locations and information on EESDI adapter.

   The Extended ESDI controller had two versions:  (see below)

      ----------------------------------------------------- ---
      |                 ::  ::  ::  ::  ::                 ||
      |                 ::  ::  ::  ::  ::                 ||
      |                 E   D   C   ::  ::                 ||
      |                             B   A  X Y Z           ||    early card
      |                                    . o-o           ||
      --------------------------+     +--+            +----+
                                |_____|  |____________|     |

      ----------------------------------------------------- ---
      |                 ::  ::  ::  ::  ::                 ||
      |                 ::  ::  ::  ::  ::                 ||
      |                 E   D   C   ::  ::                 ||
      |    Z Y X                    B   A                  ||    later card
      |    o-o .                                           ||
      --------------------------+     +--+            +----+
                                |_____|  |____________|     |

         Position A - is for floppy drive cable both floppies.
         Position B - dasiy chained data cable for all three hard drives.
         Position C - for first drive control cable.
         Position D - for second drive control cable.
         Position E - for third drive control cable.

         Primary address,  jumper  Z to Y.
         Secondary Address, jumper Y to X.

     Later version Part Number, 08F3766.

     I/O addresses used:
        Floppy drives A and B - 03F0 - 03F7
        Drives C, D and E     - 01F0 - 01F7  and  05F0 - 05F7

     DMA channels  Diskette = 2  FIxed disk = 0 or 1 (set by program).
     IRQ diskette = 6  Fixed disk = 12 or 14 (set by program).

-------------------------
H.31 - Jumper locations and information on the 'PORTED' EESDI adapter.

    The "Ported" or Portable Drive adapter was a special version of the
    standard Extended ESDI controller that had the same identical layout,
    jumper and pin configuration as the "later" version of the Extended
    ESDI controler.  The one difference was an external connector on the end
    plate of the card that could hook up the IBM "Portable drive bay"
    enclosure.  The portable controller had the same connectors in the middle,
    and I suspect that the "portable" controller was not any different from
    the stock controller.

    In a non-standard configuration, I have run run 6 ESDI drives by having
    a standard Extended ESDI controller in slot one and a PORTED controller
    in slot 2. The portable controller even had to be jumpered to the
    "secondary" position for installation.  I also have tested the card
    in the primary position (undocumented on the jumper setting in the manual,
    but it looked JUST like the standard EE-ESDI card!) running the internal
    E310 drives, and it worked just fine.

     Part Number, 08F3612.

     I/O addresses used: [looks like secondary addresses to me! - MW]
        Drives F, G and H     - 0170 - 0177  and  0570 - 0577

     DMA channels  FIxed disk = 1 or 3 (set by program).
     IRQ Fixed disk = 12 or 14 (set by program).

-------------------------
H.32 - IBM 9332 Disk drive information.

     IBM 9332 DIRECT ACCESS STORAGE DEVICE
     No Longer Available, for ordering by IBM US as of May 17, 1993.

     The IBM 9332 "Athens" fixed disk drive has models with both IPI-3
     and SCSI interfaces.  The only version attached to the RT was via
     the differential SCSI interface.  During boot time the AIX operating
     system has the ability to download microcode to the drive.

     The Models 240 and 440 drives are intended to be Rack-mounted
     in a 9309 Rack Enclosure.  The Models 250 and 450 are mounted
     in a standalone enclosure providing cooling and power.

    Model.................  240,250  440,450

    Capacity in Mb          200.3      400.6

    Format
     Number of Cylinders     1349       1349
      User                   1346       1346
      Reserved                  3          3

    Access in Milliseconds
     Average                 19.5       19.5
     Track-to-Track           3.2        3.2

    Data Rate--Mb/sec
      Maximum burst           4.0        4.0
      multisector         1.4-1.9    1.4-1.9

    Rotation Speed RPM       3119       3119

    Latency in
     Milliseconds             9.6        9.6

    Number of Actuators         1          2

-------------------------
H.33 - Pin connections and tech. info on 6153, 6154 and 6155 monitors.

 IBM 6153 Advanced monochrome Graphics adapter. - P/N 00F2357

      Screen:
        - Etched surface for reduced glare.
        - 720 dots horizontal by 512 scan lines vertical.
        - 12 inch diagonal white phosphor monochrome CRT.
      Video Signal:
        - Two-level video.
        - Maximum bandwidth of approx 25.7 Mhz.
        - Compatible with standard TTL driver.
      Horizontal Drive:
        - Free running Oscillator
        - Normally low, positive TTL pulse
        - Nominal horizontal frequency of 24.68 Khz
        - Retrace blanking time of 8.0 usec.
      Vertical Drive:
        - Free running Oscillator
        - Normally low, positive TTL pulse
        - Nominal vertical frequency of 92 Khz
        - Nominal frame rate 46 Hz.

     Pinout:
          Looking into female connector on the display cable.
          (NOT into the adapter socket).
          +---------------------------+
          |  15 13 11  9  7  5  3  1  |
           | 16 14 12 10  8  6  4  2 |
           +-------------------------+

        1 = Signal ground for vertical sync
        2 = Vertical Sync
        3 = Signal ground
        4 = Reserved
        5 = Signal ground
        6 = Reserved
        7 = Signal ground for video.
        8 = Video
        9 = Signal ground
       10 = Reserved
       11 = Signal ground
       12 = Reserved
       13 = Signal ground
       14 = Reserved
       15 = Signal ground for horizontal sync
       16 = Horizontal Sync

  IBM 6154 Advanced Color Graphics adapter.   - P/N 00F2350

      Screen:
        - Etched surface for reduced glare.
        - 720 dots horizontal by 512 scan lines vertical.
        - 14 inch diagonal shadow mask color CRT.
      Video Signal:
        - Two-level video for 6 video lines.
        - Maximum bandwidth of approx 25.7 Mhz.
        - Compatible with standard TTL driver.
      Horizontal Drive:
        - Free running Oscillator
        - Normally low, positive TTL pulse.
        - Nominal horizontal frequency of 24.68 Khz
        - Retrace blanking time of 8.0 usec.
      Vertical Drive:
        - Normally low, positive TTL pulse
        - Nominal vertical frequency of 92 Khz
        - Nominal frame rate 46 Hz.
        - Retrace blanking time of 527.0 usec.

     Pinout:
          Looking into female connector on the display cable.
          (NOT into the adapter socket).

          +---------------------------+
          |  15 13 11  9  7  5  3  1  |
           | 16 14 12 10  8  6  4  2 |
           +-------------------------+

        1 = Signal ground for vertical sync
        2 = Vertical Sync
        3 = R1 signal ground
        4 = low order red bit (R1)
        5 = R2 signal ground
        6 = high order red bit (R2)
        7 = G1 signal ground
        8 = low order green bit (G1)
        9 = G2 signal ground
       10 = high order green bit (G2)
       11 = B1 signal ground
       12 = low order blue bit (B1)
       13 = B2 signal ground
       14 = high order blue bit (B2)
       15 = Signal ground for horizontal sync
       16 = Horizontal Sync

  IBM 6155 Extended Monochrome Graphics Display
      Low voltage   90 - 137 VAC  - P/N 6848215
      Hi  voltage  180 - 259 VAC  - P/N 6848216
      Power Frequency  48 - 62 Hz

      Screen:
        - 1024 dots horizontal by 768 scan lines vertical.
        - 14 inch diagonal shadow mask color CRT.
      Video Signal:
        - 60 Hz non-interlaced.
      Horizontal Drive:
      Vertical Drive:

     Pinout:
          Looking into female connector on the display cable.
          (NOT into the adapter socket).
          +---------------------------+
          |  15 13 11  9  7  5  3  1  |
           | 16 14 12 10  8  6  4  2 |
           +-------------------------+

        1 = Signal ground for vertical sync
        2 = Vertical Sync
        3 = Reserved
        4 = Reserved
        5 = Reserved
        6 = Reserved
        7 = Video 1 Signal ground.
        8 = Video 1
        9 = Video 2 Signal ground
       10 = Video 2
       11 = Video 3 Signal ground
       12 = Video 3
       13 = Video 4 Signal ground
       14 = Video 4
       15 = Signal ground for horizontal sync
       16 = Horizontal Sync

-------------------------
H.34 - 5081 Display technical information.

        Horizontal Frequency  63.36 Khz
        Vertical   Frequence  60    Hz  non-interlaced
        Sync is on Green

        Seperate Red, Green and Blue input and output connections.

        Input  is labeled with circles with arrows pointing INTO the circles.
        Output is labeled with circles with arrows poinging OUT OF the circles.

        Output is intended to be used with daisy changed slave displays.

        Switch on back of display labeled "0 2 4" is called the "Gain" switch.
        It changes the termination value used for the video signals in the
        display.  Position 0 is used when hooking up a single display.

        RPQ 8K1679 modifies this display to 1280x1024 capability for
                   the model 016.
        RPQ 8K1680 modifies this display to 1280x1024 capability for
                   the model 019.

    NOTE: The 1280x1024 resolution is not available from the
              standard megapel display adapter.
              A Matrox PG1281/R display adapter and corresponding
              device drivers supported this adapter/display combination.

-------------------------
H.35 - Jumpers and documentation on the Ungermann-Bass IBM ethernet board.

  The IBM ethernet board was made by Ungermann-Bass, and is the exact same
  board as Ungarmann-Bass model 2273A NIC Baseband adapter.
  Ungarmann-Bass may be reached direct at 1-800-873-6381.
  With the gold fingers towards your stomach, and the bracket on the right
  with the electronics up, the IRQ jumpers are just above the gold contacts.
  The Address jumpers W10 thru W13 are to the left of the prom about the
  middle of the board.  The unlabeled jumpers (W14 on some boards) on the
  almost far left are the timer interrupt interval.  The jumper connects
  only one pair of pins.

          1    2    3    4
  W14    . .  . .  . .  . .    position 1 = interrupt ever  9.1 ms
                               position 2 = interrupt ever 18.3 ms
                               position 3 = interrupt ever 36.6 ms
                               position 4 = interrupt ever 73.2 ms

  IRQ jumpers are labeled:
   IR3 IR4 IR5 IR6 IR7 IR2 <--- IR2 is really IRQ 9, all others are correct.
    .   .   .   .   .   X      connect only one vertical pair of pins.
    .   .   .   .   .   X      IRQ9 is the factory default.

  I/O Memory address jumpers  (Labled W10 thru W13)

   W10   W11   W12   W13
   . .   . .   . .   . .

   XXXX     =  jumper is connected two adjacent pins together.

   X        =  Jumper is actually only jumpering ONE pin, the other side
   X           of the jumper is hanging off of the row of pins and is
               just there for future use.

   W10   W11   W12   W13    ADDR        W10   W11   W12   W13    ADDR

 ========================   ======  +   ======================   ======
   X     X     X     X              |   X     X     X
   X  .  X  .  X  .  X  .   080000  |   X  .  X  .  X  .  XXXX   0C0000
 ========================   ======  +   ======================   ======
         X     X     X              |         X     X
   XXXX  X  .  X  .  X  .   088000  |   XXXX  X  .  X  .  XXXX   0C8000
 ========================   ======  +   ======================   ======
   X           X     X              |   X           X
   X  .  XXXX  X  .  X  .   090000  |   X  .  XXXX  X  .  XXXX   0D0000
 ========================   ======  +   ======================   ======
               X     X              |               X
   XXXX  XXXX  X  .  X  .   098000  |   XXXX  XXXX  X  .  XXXX   0D8000
 ========================   ======  +   ======================   ======
   X     X           X              |   X     X
   X  .  X  .  XXXX  X  .   0A0000  |   X  .  X  .  XXXX  XXXX   0E0000
 ========================   ======  +   ======================   ======
         X           X              |         X
   XXXX  X  .  XXXX  X  .   0A8000  |   XXXX  X  .  XXXX  XXXX   0E8000
 ========================   ======  +   ======================   ======
   X                 X              |   X
   X  .  XXXX  XXXX  X  .   0B0000  |   X  .  XXXX  XXXX  XXXX   0F0000
 ========================   ======  +   ======================   ======
                     X              |
   XXXX  XXXX  XXXX  X  .   0B0000  |   XXXX  XXXX  XXXX  XXXX   0F8000
 ========================   ======  +   ======================   ======

-------------------------
H.36 - RT Token Ring card jumpers and addressing.

    The Token-Ring card has a 9-pin female connector, and usually a green
    dot sticker on the metal plate, but not always.
    The adapter card had two versions, early and late.

    For both versions, with J1 and J2 to the left, indiates no proms located
    in the sockets shown by the XXX's.

      ----------------------------------------------------- ---
      |       ...  ...  +---------+            ...         ||
      |       J1   J2   |         |            J5          ||=|  9-pin connector
      |                 +---------+                        ||=|
      |  XXX                                               ||
      |  XXX                                               ||    early card
      |   XXX                 YYYZZZ J3                    ||
      --------------------------+     +--+            +----+|
                                |_____|  |____________|     |

      ----------------------------------------------------- ---
      |       ...  ...                      ...  ...       ||
      |       J1   J2                       J5   J6        ||=|  9-pin connector
      |                                                    ||=|
      |  XXX                                               ||
      |  XXX                                               ||    late card
      |   XXX                 YYYZZZ J8                    ||
      --------------------------+     +--+            +----+|
                                |_____|  |____________|     |


-------------------------
H.37 - What are the differences between the 032, APC and EAPC processor types.

    The standard 032 processor in the original models of the RT had the
    following features:
      * 170 Nanosecond processor cycle time.
      * 16  32-bit general purpose registers
      * 16  32-bit system control registers, including:
            - countdown timer register
            - exception control registers
            - interrupt request buffer register
            - instruction address register
      * 118  2 and 4 byte instructions with storage, branch, control, and
        integer math, including multiply and divide step instruction.
      * Memory Managment Unit with translation look-aside buffers, and
        address translation including:
            - 40-bit virtual address.
            - 256 Megabyte memory segments.
            - Multiple independent virtual address spaces.
            - address space size of 4 gigabytes.
            - demand paging.
            - page size of 2048 or 4096 bytes.
            - Memory protection.
            - Real memory addressability of up to 16 Megabytes.
            - Hardware assist for load real address

    The Advanced processor (APC) has these enhancements to the original
     processor.
      * 100 Nanosecond processor cycle time.
      * Overlapped Load and Store operations.
      * Several instructions are serialized to allow for better memory and I/O
        operations.
      * Additional exception control register information.
      * Instruction prefetch, and 16 byte loop detection.
      * MMU allows multiple outstanding load and store requests
      * On board 20 Mhz MC68881 floating point processor.
            - Trigonometrice and transcendental functions.
        - Seven different data types and conversions.
      * I/O interface enhancements.

    The Enhanced Advanced processor (EAPC) has these changes from the
    original and APC processor.
      * 80 Nanosecond processor cycle time.
      * 16 Megabytes main memory on the processor board.
      * Faster operation of the MMU.
      * MC68881 and one I/O chip removed.
      * Intended to be used with an Advanced Floating Point Accellerator.

-------------------------
H.38 - Speed and capability of the Floating Point options for
              the RT computers.  FPA, MC68881, AFPA.

    All models of the RT systems running AIX can run with no floating
    point hardware assist and provide for simulation routines for floating
    point operations.

    The standard Floating Point Accellerator (FPA) contains instructions
    for general floating point operations, but does not include direct
    hardware support for trancendental functions (sin, cos, tan, ect..).

    The model 115 and 125 computers, with the Advanced Processor card
    include a Motorola MC68881 chip running at 20 Mhz.  This chip is
    faster than the FPA, but not as fast as the Advanced Floating
    Point Accellerator (AFPA).

    In genral the FPA is slower than the MC68881, which in turn is
    slower than the AFPA.   The FPA advantange is it can run in
    parallel with the processor, providing some overlap of operations.

-------------------------
H.39 - Where can I obtain a replacement battery?

   The battery located under the front cover of the tower model RT next to
   the keylock, and inside the case on the desktop unit behind the keylock
   mounting bracket. It maintains the real-time clock for the system when
   the power is off.  It also maintains the non-volatile ram (NVRAM) contents.
   The NVRAM contains several items, among which are:
   the last error record, and the current list of boot devices.

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: Matt "C P." Rush <[e-mail]>
   Subject: RT batteries through Radio Shack
   Date: 26 Oct 93 21:10:43 GMT

    Just in case anyone out there needs to replace the battery in
    their RT, they can be Special Ordered through your local Radio Shack.
    Amazingly, the IBM-RT is actually listed in their battery cross-
    reference, but in case YOUR Radio Shack is lame,
    the part no. is:   CLB-5293/W

    The painful thing is the PRICE:  $15.99.  I decided that it
    wasn't that bad to do a 'date' command every time I booted up. :-)
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

  My notes here..
    This is average price for a lithium computer battery.
    The batteries on some RT systems that I have used, have lasted as long as
    6 years before needing replacement, others are still going strong,
    so it is a relatively small price comared to other replaceables.

    Someone asked:
    > Are these batteries any different from garden-variety AT batteries?

    There IS NO one common AT battery.  Some are 3V some a 6V.  Some are plug
    in, some snap in more traditional battery carriers.

    The RT battery (IBM P/N 6299201) for the RT is 6.8 volts!

    Last I heard, IBM wanted $25.00 US for a RT battery.  The Radio Shack
    battery sounds like a good deal, if it is a proper replacement.
    I have seen FIRES start in an RT that had an improper battery!

    At least one user has reported using AA batteries in a traditional
    carrier.
    As always.. caveat emptor, user beware, your milage may vary, ect..
    - MW.

-------------------------
9.0   Credits, Acknowledgements and other information.

X.1 - Acknolowgements and copyright information.

This file is provided AS IS with no warranties of any kind as to the
usefullness/correctness of these procedures/questions.  The author
shall have no liability with respect to the infringement of copyrights,
trade secrets or any patents by this file or any part thereof.  In no
event will the author be liable for any lost revenue or profits or
other special, indirect and consequential damages.

IBM, AIX, AT, XT, RT, RT PC and RT Personal Computer are trademarks of
  International Business Machines Inc.
UNIX is a registered trademark of American Telephone & Telegraph in the
  United States of America and other countries.
Any other trademarks not specifically mentioned are owned by their respective
  companies.

Credits:
        The following people have either submitted articles for
        inclusion, made suggestions, or had parts of old articles
        included within re-arranged information.
        If you want your name dropped please let me know.

Marc Brett              <[e-mail]>
Jon Brinkmann
John Carr               <[e-mail]>
David L. Crow           <[e-mail]>
Bjorn Engsig            <[e-mail]>
eliot                   <[e-mail]>
Mike Johnson            <[e-mail]>
John R. Moore           <[e-mail]>
Francois Normant        <[e-mail]>
Gerald Oskoboiny        <[e-mail]>
Richard Rogers          <[e-mail]>
Matt Rush               <[e-mail]>
Russell Schulz          <[e-mail]>
David Snearline         <[e-mail]>
John Tracey             <[e-mail]>
Pim Zandbergen          <[e-mail]>

====================== end of FAQ ibm-rt-faq/hardware =========================

AIX..... NOT just another UNIX.
Mark Whetzel                          | My own RT system.. My own thoughts..
DOMAIN: [e-mail]      | IBM RT/135 running AIX 2.2.1
UUCP ..!menudo!lobster!antimatr!markw | comp.sys.ibm.pc.rt FAQ maintainer