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Text File | 1986-09-20 | 38KB | 1,154 lines

TURBO ROM Theory of Operation The TURBO ROM for Kaypro computers interfaces the CP/M operating system to the actual hardware such as video display and disk drives. It allows the addition of expansion hardware such as high capacity floppy disks, multiple hard disks and Advent Products RAM disks. It automatically senses the presence of this hardware and provides the appropriate drivers to allow the operating system to fully use these new devices. The following notes may be useful to those wishing to understand the operation of the ROM. COLD BOOT When power is applied, or the reset button is pressed, the following sequence of events is followed. 1/ A delay of 100 ms to allow for some of the peripheral chips to achieve equilibrium. (MOSTEK parts are much slower than Zilog) 2/ The peripheral devices are programmed with default values such as baud rate etc. 3/ The video driver is initialized and the screen cleared. 4/ The sign-on message is printed. 5/ The presence of the WD1002 hard disk controller is detected, by seeing if it comes not busy within 3 seconds. If so, drive one is tested for ready. We wait up to 20 seconds for it to come up to speed. (Note Drive One is connected to J2 of controller) When ready we issue a restore command and wait up to 25 seconds for the completion. (If any of these tests fail then we have no hard disk) 7/ An attempt is then made to read a 1024 byte sector (8) from the first cylinder of the disk. If this is successful then we check to see if the sector is a valid parameter sector. On 83 machines the main part of the hard disk initialization code is contained on the second half of the sector. The first 512 bytes of this parameter sector contain the characteristics of the drives and the bad track mappings. *84 Machines Only If this read fails we attempt to read a 512 byte sector (16) from the same cylinder. If this is successful we check for valid parameter sector. If we have a succesful 512 byte sector read but an invalid sector then we assume 512 byte sectors of standard Kaypro layout. 8/ *83 Machines Only The code read from the parameter sector is used to check for the presence of a second Hard disk. Parameter tabels for these drives are set up in memory along with bad track maps. 9/ The lowest (in terms of select logic 0,1,2,3) floppy drive is examined for the presence of a spinning diskette. If detected the logical drive ordering is as follows: A -> V = Floppy Drives X -> Y = Hard Drives (if present) Z = Ram Disk (if present) If no floppy detected the logical drive ordering is: A -> V = Hard Drives (if present) X -> Y = Floppy Drives Z = Ram Disk (if present) 10/ An attempt is then made to read the first sector of logical drive "A". This parameter sector conforms with the standard Kaypro layout, having the load address, execution address and the number of sectors to be loaded. If we are running on a Kaypro 10 with a 512 byte/sector hard disk a check is done to see if the system to be loaded will over-write the Host Buffer area (see memory layout for explanation), and if this occurs (generally only with a 63K system) the Host buffer is shortened to 512 bytes and floppy disk formats with > 512 bytes/sector are flagged as illegal. 11/ The system is then read into memory and control is tranferred to this system at the specified address. If the supplied TURBO-BIOS is used (highly recommended) then further initialization is performed. The nature of this initialization can be modified by the supplied configuration program TURBOCFG. WARM BOOT On a Warm Boot an attempt is made to read from the logical "A" drive a fresh copy of the Command Processor and Basic Disk Operating System (BDOS). The configuration program TURBOCFG can be used to change the default drive for this operation. We recommend using this advanced option only if you really know what you are doing. An example may be to warm boot from the RAM disk without making it drive A. However, it must be SYSGENed before the first warm boot takes place. DISK SELECT (and Deselect) Floppy drives have removable media while Hard Disks and Ram Disks have fixed media. Drives with removable media are treated differently at select time. If this is the first select since a disk reset then we re-determine the format of the diskette in the drive. (This operation can be inhibited under special circumstances). If the format cannot be determined a BDOS Select error will occur, unlike most BIOS's which would generate a bad sector error. Naturally a select error will also occur if an attempt is made to access a non-existent drive. A period of time after the last disk operation, a deselect process occurs. This first makes sure the contents of the De-Blocking buffer are written back to the disk if required. Then the floppy motor is turned off and if needed both floppy drives are deselected (lights turned off). If Hard disks are present then each drive seeks the innermost formatted cylinder and then non-existent drive zero is selected. This final step deselects the actual hard drives. DEFINITION OF TABLES USED BY THE ROM DATA PARAMETER HEADERS (Commonly alled DPH's) The DPH for each logical drive is extended by 2 bytes compared to the standard DRI definition (see CP/M manual if you are not familiar with this). These 2 bytes preceed the normal 16 bytes. The first byte contains information on the logical/physical mapping of the drives. ------------------------------------------------------------ Byte0 - logical/physical drive mapping physical: bit 7 -- reserved for future use by Plu*Perfect Systems bit 6,5,4 000 = Advent Products RAM disk (up to 2 MBytes) 001 = reserved for future use 010 = Physical Hard Drive 0 (up to 56 MBytes) 011 = Physical Hard Drive 1 ( " " " ) 100 = Physical floppy 1 (48 or 96 TPI) 101 = Physical floppy 2 110 = Physical floppy 3 111 = Physical floppy 4 logical: bit 3-0 logical drive A-P 0000 = A 0001 = B 0010 = C . . . . . . 1111 = P ______________________________________ In the second byte, some physical charactistics of the Drive are coded. Byte1 - drive characteristics byte defined as follows:- ****************FLOPPY DRIVE bit 7 - 0 = if drive is 48 tpi 1 = " " 96 tpi bit 6 - 0 = redetermine media on fresh select(normal) 1 = don't redetermine media on fresh select (used when externally set disk format) bit 5 - unused *****************HARD DRIVE Advent Format - bit 7,6,5 number of heads (minus one) Kaypro 512 byte/sector format- bit 7 0 = platter A (heads 0,1) 1 = platter B (heads 2,3) bit 6,5 unused *****************RAM DRIVE bit 7,6,5 unused *********** All drive types bit 4 0 = Use ROM DPB tables 1 = Use RAM DPB tables bits 3,2,1,0 Use DPB 0-15 from rom or ram table Bytes 2 - 18 - Standard DRI data parameter header. DATA PARAMETER BLOCK (DPB's) The DPB's used by the ROM are 3 bytes longer than the standard definition given by DRI (see CP/M manual if you are not familiar with this). These 3 extra bytes precede the normal 15 bytes. There is a word which points to a sector translation table address. This may be zero, a ROM address which is not accessable to external programs without bank switching, or an externally loaded table in high RAM. There is then a Byte which characterizes the type of format associated with this DPB. The bits in this byte are interpreted as follows: 1/ For Floppy Drives: (Media) bit 7 - 0 = disk is in 48 tpi format 1 = disk is in 96 tpi format bit 6 - 0 = standard data sense 1 = inverted data bus (only available on 84 ROM) (used only on machines that used chips like 1771/91 without inverters) bit 5 - 1 = single density 0 = double density bit 4,3,2 - Use algorithm 0-7 to compute physical cylinder, track, sector and side. Note algorithm 7 is reserved for external code, which the user may load. See later for definition and how to load this code. Predefined Algorithms ----------------------------------------------- 000 - for 512 byte Kaypro hard disk format (see below) ----------------------------------------------- 001 - for 512/1024 byte Advent hard disk formats (see below) ----------------------------------------------- 010 - single sided floppy phy.cylinder =track phy.track =track phy.sector =sector phy.head(side) =0 ----------------------------------------------- 011 - double sided Kaypro/Advent floppy bias =10 phy.cylinder =int(track/2) phy.track =phy.cylinder phy.head(side) =mod(track,2) phy.sector =sector + side*bias ----------------------------------------------- 100 - Micro Cornucopia/Advent 96 tpi, Same as Kaypro except bias =20 ----------------------------------------------- 101 - double sided (single long track) Note that zero based sector numbering assumed, fits Legacy formats phy.cylinder =track phy.track =track phy.sector =sector phy.head(side) =0 if sector < phy_sect/side =1 if sector >= phy_sect/side ----------------------------------------------- 110 - double sided (odd tracks on back but no sector skew) Same as Kaypro except bias =0 ----------------------------------------------- 111 - External routine, parameters in registers on call and return. ENTRY EXIT HL none physical cylinder to seek DE HSTTRK physical track for floppy ctrl B HSTDRV (dph byte 1) physical head (side) C HSTSEC physical sector ------------------------------------------------ bit 1,0 - 00 = 128 physical sector length 01 = 256 10 = 512 11 = 1024 ------------------------------------- 2/ For Hard Disk Drives: bit 7,6,5 unused (These bytes compatible with floppy use) bit 4,3,2 000 -Kaypro 10 original format 512 byte sectors (algorithm for track sector) phy.cylinder = (track + offset)/2 offset = 0 if track < 4 offset = track - 4 if 3 < track < 8 offset = 4 if track > 7 phy.track = n/a phy.sector = sector phy.head = mod(track+offset,2) + drvbyt(7)*2 drvbyt(7) is bit 7 of byte 1 of DPH (note we abandon trying to maintain duplicate directory on back of platter, if problems, then reformat with our new format) 001 -Advent Hard disk format 512/1024 byte sectors phy.cylinder = trackx/#heads phy.track = n/a phy.sector = sector phy.head = mod(trackx,#heads) (Note trackx = badfnc(track). This corrects desired track for bad tracks. The bad track function is performed by the following algorithm. I:=0 TRACKX:=TRACK DO WHILE(BADTRK(I) >= TRACK) TRACKX:=TRACKX +1 I:=I + 1 END Where badtrk(i) is a list of bad physical tracks which is terminated with FFFFH entry. We support a maximum of 126 bad tracks per physical drive.) bit 1,0 - 00 = not supported 01 = not supported 10 = 512 byte sectors (only available on 84 ROMs) 11 = 1024 byte sectors ------------------------------------------------ 3/ Advent Ram Disk Drive: bit 7,6,5,4,3,2 unused bit 1,0 - 00 = 128 byte sectors 01 = not supported 10 = " " 11 = " " ------------------------------------------------- In ROM we have a maximum of 16 DPB's DPB# 0 Standard Kaypro SS (512 byte sectors) floppy 1 Standard Kaypro DS (512 byte sectors) floppy 2 Advent SSDD 448 tpi(1024 byte sectors) ( handles Osborne SSDD) floppy 3 Advent DSDD 48tpi (1024 byte sectors) floppy 4 Advent DSDD 96tpi (1024 byte sectors) floppy 5 Micro C DSDD 96tpi (512 byte sectors) floppy 6* Xerox 820 SSSD (128 byte sectors) floppy 7* Osborne SSSD (256 byte sectors) floppy 8* Epsom QX-10 (U.S. format - not European) floppy 9* Kaypro 10 (original hard disk format) hard 10* 11* 12* 13* reserved for future expanison 14* 15* * only available on 84 ROMS In high memory we store the DPB's who have to be dynamically changed/added. The first DPB is a reserved entry for use by external programs who wish to set up a foreign floppy format for the ROM to work with. The second is always the RAM disk if it exists. Following this are the various Hard disks (Advent Format only) which are actually read in from the parameter sector of the hard disk. These DPB's are stored in descending memory order (unlike DPH's above). HIGH MEMORY ARRANGEMENT The ROM uses the very top of the Kaypro RAM for its working storage. The amount of memory used depends on the physical configuration, but in all cases, memory is dynamically allocated at cold boot time so that the amount of memory available to user programs is maximized. The very top of memory is of fixed layout (which varies slightly between 83 and 84 ROMs) and this is useable by programs which need to find out about the current environment. topmem equ 0FFFFH ;************************* ;ROMID is 8 byte string of following layout ; db checksum ;zero sum of top 8 bytes in memory ; jmp romentry ;general ROM entry point ; db version ; BCD ver.rev, (hi bit set '84) ; db 'PPS' ;************************* ;fixed pointers and storage which are guarranteed to be preserved in ;future releases of the ROM dphptr: dw numdrv ;pointer to start of DPH table dpbptr: dw numdpb ;pointer to start of RAM DPB's hstptr: dw hstbuf ;pointer to Host buffer ;This is the lowest area used by ROM intptr: dw intvec ;pointer to start of interrupt vector extptr: dw tsalgr ;pointer to external trk/sctor code hrdptr: dw badtr0 ;pointer to hard/floppy disk parameters ;fixed storage that varies between 83 and 84 machines 83 84 -------- --------- safptr: dw safcod dw x ;reserved cursor: dw x cursor: dw x ;video cursor clkent: dw clkdrv ;routine to ;clock curmin: db minutes ;current time db hours ;*********************** Interrupt vector for all devices. 83 84 -------- -------- pioBvc ;modem dialer pioAvc ;RTC interface sioCv3 ;serial printer sioCv2 sioCv1 sioCv0 pioDvc ;unused sioDv3 ;Modem or Unused serial pioCvc ;printer sioDv2 pioBvc ;unused sioDv1 pioAvc ;system port sioDv0 ; sioAv3 sioAv3 ;serial data char rec.(error) sioAv2 sioAv2 ;serial data char rec. sioAv1 sioAv1 ;serial data ext. status sioAv0 sioAv0 ;serial data Tx buffer sioBv3 sioBv3 ;keyboard char rec. (error) sioBv2 sioBv2 ;keyboard char rec. sioBv1 sioBv1 ;keyboard ext. status sioBv0 sioBv0 ;keyboard Tx buffer intvec: ;start of vectors aligned on ;16 byte boundary ;********************* Stack space for interrupt handlers and ROM ;******************** Code, DIRBUF and other variables ;******************** Area for externally defined floppy drive information xtran: ds 36 ;36 bytes of physical translation table ds 55 ;SPACE for code referred by labels ; invmap and mapit db fmt ;current format number jmpr invmap ;inverse trk/sector/side tsalgr: jmpr mapit ;cylinder/sector/head ;******************** Miscellaneous disk/video/and other variables which may change with future ROMS implementation. ----------- However the following structure will remain intact though it will doubtless move. disblk: db .. ;84 machine video blanking disable (00/FF) (not currently used) smflag: db .. ;84 machine retricted to 512 byte sectors stldly: db z ;current floppy head settling delay (ms) hldly: db y ;current floppy head load delay(ms) fstprt: db x ;current floppy step rate (ms) ftime4: db x,y,z ;array of floppy time constants for each drive ftime3: db x,y,z ftime2: db x,y,z ftime1: db x,y,z muxflg: db .. ;flag for presence of Advent decoder board fstat: db .. ;current floppy arrangement ;7 - Drive 4 96 tpi ;6 - Drive 4 exists ;5 - Drive 3 96 tpi ;4 - Drive 3 exists ;3 - Drive 2 96 tpi ;2 - Drive 2 exists ;1 - Drive 1 96 tpi ;0 - Drive 1 exists (always true) wdflag: db .. ;7 - if parameter sector successfully read ;0 - WD 1002 controller detected sltmsk: db .. ;floppy select mask ; 00000011B ;normal 2 lines ; 00000001B ;Kaypro 10 hard disk connected precp1: db .. ;Hard Drive 2 precomp cylinder(coded) step1: db .. ; " " " step rate (coded) mxcyl1: dw ... ; " " " maximum formatted cylinder badtr1: dw list1 ; " " " pointer to start of bad track table precp0: db .. ;as above for drive 1 step0: db .. mxcyl0: dw ... badtr0: dw list0 ;POINTED TO BY HRDPTR AT TOP OF MEMORY polflg: db .. ;set to 00 if type-ahead keyboard (else FF) belchr: db .. ;bell character for keyboard, may have click bit --------------- ******************************** ************************************** * Run time determined storage areas * ************************************** Actual list of n*18 drive descriptor bytes where n is logical number of drives. These are arranged as described above. numdrv: db n ;logical number of drives ;pointed to by dphptr Followed by DPH for each drive as described above. NOTE that DPH's ascend in memory above the NUMDRV byte. ************************************************************ In RAM DPB tables decribed above -- note they descend in memory though the number of DPBs byte is still at bottom of list each DPB of following layout dw xtran ptr db media byte ds 15 ;normal DRI definition Actual list of RAM dpb's in following order (descending in memory) 0 - always externally definable floppy 1 - RAMDISK (computed at cold boot) 2-15 up to 14 more formats read in from hard disk parameter sector (future ROM releases may limit number of logical hard disks to 13) numdpb: db ;number of RAM dpbs in this ;configuration, the first ;is always the externally ;definable floppy ;*********************** ;Hard Disk bad track lists (if any) list1: dw ... dw ... dw FFFFH list0: dw ... dw ... dw FFFFH ************************ hstbuf: ds 1024 ;deblocking buffer ;init code changes to 512 ;bytes if system loaded too high ;on Kaypro 10 with 512 ;byte sectors ************************ lowest area used in high Ram by ROM ADVENT PRODUCTS ELECTRONIC RAM DISK The RAM disk is located at ports 88H thru 8BH. 88H - data bi-directional 89H - sector (6 lo bits only) 8AH - track register (7 lo bits per board, hi bit board select) 8BH - status register (bit 0,1 00,01,10,11 are 256,512,768,1024K respectively. Bit 2 is 0 if board is present and otherwise is pulled up. Status register returns xxxxx000 = 256k xxxxx001 = 512k xxxxx010 = 768k xxxxx011 =1024k xxxxx1xx = ram disk not present Then we write 8AH with 80H and repeat read of 8BH for second board. RAMDISK has following DPH XLT ptr 0000 ;no sector translation SCRATCH 0000 0000 0000 DIRBUF ;pointer to directory buffer CURDPB ;always points to DPB current 0000 ;no directory checksum ALVRAM ;pointer to size dependent area RAMDISK has following DPB XTRN: dw 0000 ;no sector translation MEDIA: dw 00 ;128 byte sectors SPT: dw 64 BSH: db x ;x = 3 for 256K ; = 4 for 512K ; = 5 for 768,1024K ; = 6 for > 1024K BLM: db 2**x - 1 EXM: db 2**(x-3) - 1 DSM: dw 2**(6-x).(n+1).2**5 - 1) - 1 DRM: dw 2**(3+x) - 1 AL0: db 0C0H AL1: db 000H CKS: dw 0000 OFF: dw 0001 Sector 63 of track 0 is initialized with a copy of the first 128 byte of the ROM. On subsequent resets this is compared and if a match is detected the directory of the RAM disk is not erased. ************************************************* FLOPPY DISK FORMATS The Turbo ROM will recognize and can use directly the following floppy disk formats:- 83 84 --------- --------- Kaypro SSDD Kaypro SSDD Kaypro DSDD Kaypro DSDD Advent SSDD Advent SSDD Advent DSDD 48 Advent DSDD 48 Advent DSDD 96 Advent DSDD 96 Micro Cornucopia 96 Micro Cornucopia 96 Epson QX-10 DSDD 48 (U.S.) Osborne SSSD Xerox 820-1 SSSD In addition any other CP/M 5.25" soft sector format may be set up using the TURBOSET program which is available separately as part of the Plu*Perfect Systems' MULTI-COPY package. The Advent formats mentioned above have the following description. 1) SSDD Physical Sector Length 1024 bytes Physical Sector Order 1,4,2,5,3 Logical Sectors/Track 40 Number of Cylinders 40 Reserved Tracks 3 CP/M allocation size 1K Directory Entries 64 Reserved Directory Groups 2 Total size 185K *note that this format is identical to the Osborne SSDD except for the physical sector order 2) DSDD 48 Physical Sector Length 1024 bytes Physical Sector Order 1,4,2,5,3 -side 0 11,14,12,15,13 -side 1 Logical Sectors/Track 40 Logical Tracks 80 Number of Cylinders 40 Reserved Tracks 2 CP/M allocation size 2K Directory Entries 256 Reserved Directory Groups 4 Total size 390 K 3) DSDD 96 Physical Sector Length 1024 bytes Physical Sector Order 1,4,2,5,3 -side 0 21,24,22,25,23 -side 1 Logical Sectors/Track 40 Number of Cylinders 80 Number of Logical Tracks 160 Reserved Tracks 2 CP/M allocation size 2K Directory Entries 256 Reserved Directory Groups 4 Total size 790 K TURBO ROM VIDEO FEATURES The Turbo ROM provides a number of new video features compared with the standard Kaypro. These differ between the 83 and 84 versions. Video Blanking: Both ROM's provide a screen saving video blanking after about ten minutes of waiting for keyboard input. However, on 83 machines this feature requires a modification to the video circuit. This is optional and the blanking will not occur unless the change has been made. Because the ROM has no way of knowing whether the change has been made, the unblanking keystroke will not be ignored as it is with the 84 ROM. The 83 video change is made simply by purchasing a replacement character generator ROM and putting it into the circuit. Alternatively, people with electronic circuit experience, can make a small modification to the main circuit board to achieve the same effect. Details are available on request. Screen Dump: While not a direct feature of the Turbo ROM, the TURBO BIOS supplied with the ROM has character (not graphic) screen dump to printer capability. The ROM actually provides the support for this feature but it must be externally activated, for more details see the source code to the BIOS and the following description of the ROM Entry Points. The Screen Dump must be explicitly enabled by using TURBOCFG. Changes to Video Control Codes and Escape Sequences: Some changes to the behaviour of the video compared to the standard Kaypro ROM's have been made. These are generally for consistency or to correct bugs in the original implementation. a) Control Characters that are not used by the video are now "swallowed" rather than generating Greek characters or Fine Line graphics. b) On 83 machines the underline cursor no longer destroys true underline characters on the screen when moved through their positions. c) On 84 machines the ESC G/ESC A sequences are implemented identically to the 83 machines. That is the 32 characters (lower case) from the grave accent (60 Hex) through the DELete (7F Hex) will produce the the corresponding graphic character in position 0-31 (decimal) in the character ROM if the video sequence ESC G has been recieved. When the sequence ESC A is recieved the lower case characters produce themselves. On the 83 character ROM's thes 32 characters are normally greek and mathematical symbols. On the 84 character ROM's these characters are normally the Fine Line graphic set. On Foreign Language Kaypro's these characters are selected european characters. d) On 84 machines the sequences ESC B 7/ESC C 7 have a slightly different effect. The standard video defaulted to a 24 line scrolling window with the 25th line also scrolling. The Turbo ROM is either a 25 line scrolling display or a 24 line scrolling display with the 25th line locked. The difference is minor unless you wish to reconfigure some of your application programs to make use of the 25 line screen. Note that the ROM scrolling is much faster if a 25 line scrolling region is enabled. Also, scrolling is much faster if no video attributes have been used since the last clear screen. New Features: a) Hard Tabulations. The standard video ignored the tabulation character, "^I". Both 83 and 84 ROM's expand this to 8 column fixed tabs. This is mostly of use to user's of Plu*Perfect Systems NOTEPAD module of the Backgrounder, as most programs expand tabs in software. b) Insert and Delete Character. Two new control codes are now interpreted to insert and delete characters. "^A" will cause the next character recieved to be inserted at the current cursor position. "^B" will delete the character currently at the cursor position. Both of these controls are limited to the current line, i.e. inserting characters will move the characters to the right of the cursor but will not cause any that are displaced past the end of the line to wrap. These new features are again of interest to users of Plu*Perfect Systems' NOTEPAD module of the Backgrounder. c) On 84 machines there is now a method of dynamically modifying the type of cursor used. ESC U n will cause a new cursor whose characteristics are defined by the ascii character "n". The cursor is bit encoded into this character and the bit positions have the following meaning. bits 6,5 - blinking 00 - no blinking 01 - no cursor 10 - fast blinking 11 - slow blinking bits 4,3,2,1,0 - cursor height 00000 - full block cursor (16 scan lines) 00001 - 00010 - ..... 01110 - thicker underline (2 scan lines) 01111 - thin underline cursor (1 scan line) d) Disable on screen clock display. On 84 machines which have either a built in Kaypro clock or and Advent Products clock, the on screen display of the time may be temporarily disabled with ESC C 8 and re-enabled with ESC B 8 Note that the clock display is automatically disabled if a 25 line scrolling screen is selected. e) Switch character generators. On 84 machines which are correctly wired, an altenate character set may be chosen with the following ESC B 9 and the original re-selected with ESC C 9 This additional character set would normally reside in the other half of a 27644 character ROM. True 84 machines are actually wired to accept this chip but unfortunately Kaypro did not test the circuit and a minor modification is required. On older Kaypro 10's a small circuit modification is required, please contact Advent Products if you wish to make use of this feature of the TURBO ROM. ENTRY POINTS INTO THE TURBOROM The TURBO ROM in general preserves the standard entry points that have been used with only small differences by all CP/M Kaypros since the KAYCOMP. There are naturally some extensions which provide additional features. One major addition is the creation of a standard entry mechanism that can be used regardles of whether an 83 or 84 machine is being used. If a utility wishes to call the ROM it should load the page zero address it wishes to call into the L register and then call 0FFFCH in high memory. All the bank and stack switching tasks will be automatically taken care of. However, direct calls to the ROM should be avoided in normal application programs as they severely limit portability of the program. Entry Points: 0000 Machine Restart, cold boot 0003* Disk Reset 0006 Initialized video driver 0009* Initialize unit record hardware 000C* Deactivate Host buffer if not written (HOME) 000F Select disk for next access 0012 Set Track for next disk access 0015 Set Sector for next disk access 0018 Set DMA address for next disk access 001B Read Sector 001E Write Sector 0021* Sector Translation (dummy, delayed to SETSEC) 0024 Turn on the Floppy drive motor 0027* Turn off floppy motors, Deselect hard drives, flush Host buffer 002A Keyboard input status 002D Keyboard input 0030 Keyboard serial output, use with caution 0033 Serial Data port input status (TTY) 0036 Serial Data port input (TTY) 0039 Serial Data port output (TTY) 003C Centronics printer output status (LPT) 003F Centronics printer output (LPT) 0042 Serial Data port output status (TTY) 0045 Video output (CRT) 0048* Ten millesecond delay 004B# Serial Printer input status (UL1) [83=TTY] 004E# Serial Printer input (UL1) [83=TTY] 0051# Serial Printer output (UL1) [83=TTY] 0054# Serial Printer output status (UL1) [83=TTY] 0057# Reload system 005A# Get next screen dump character 005D# Set cursor type 0060# One millesecond delay 0063# Initialize DPH -----DO NOT USE 83 Roms 84 Roms 0067# Hard Disk Seek -----DO NOT USE 0067# Kaypro Clock 006A# Hard Disk Setup-----DO NOT USE 006A# Advent Clock 006D# Kenmore CLock Rom Entry Point Specifications: (* Changes from Original Kaypro) (# New entry points) 0003 Disk Reset -- ENTRY - none, EXIT - none Simply resets the Host Buffer Active flag and the Unallocated Sector Counter. This follows exactly the definition in the latest versions of DRI documentation (warm boot). The Kaypro ROM's used this entry point for other internal purposes. 0009 Initialize Hardware -- ENTRY -- DE points to list of port,data pairs A number of entries in list (len/2) (see TURBO-BS.PRN for example of use) EXIT -- none This entry allows the physical devices to be set up with any byte pattern. The original Kaypro entry point always used its default values. 000C Home -- ENTRY -- none, EXIT -- none This entry point follows the DRI definition, of reseting the Host Buffer Active flag if the buffer does not have a pending write. It also calls the set track entry with an argument of zero. The Kaypro ROM's in many cases also performed a physical seek to track zero. This is unnecessary. 000F Select Disk -- ENTRY -- C - desired logical drive 0-15 E - bit 0=0 if this is first select else bit 0=1 EXIT -- HL = points to DPH for this drive if select was successful = 0000 if either drive does not exist or the floppy format was not determinable The main differences from almost all of the Kaypro ROM's is the correct use of the lo order bit of the E register as specified by Digital Research. This means that any program that correctly uses the BDOS facilities to log in a new drive will have the media correctly determined after a disk change. On the Kaypro ROM's the only time a change could be made between say single and double sided disks was after a warm boot. Popular programs like SWEEP could not be used with a mixture of disk formats. (Note that Plu*Perfect Systems' CP/M enhancements included a BDOS patch to correct this, when the TURBOBIOS is installed this patch is overwritten and original contents replaced) 0015 Set Sector -- ENTRY -- BC = logical sector for next request EXIT -- none This routine combines the functions of the old Sector Translation routine. It must be called after the select disk function has been called, so that the correct sector translation table can be used. This is identical to the BDOS use of the original two separate entry points. 0021 Sector Translation -- ENTRY -- BC = logical sector for next request DE = pointer to translation table EXIT -- HL = logical sector This routine is a totally dummy routine and for efficiency all of its functions are now performed in the Set Sector Routine. 0027 Motor Off -- ENTRY -- none, EXIT -- none Before performing its major deselect function this entry check the Host Buffer for a pending write and if there is one the buffer will be written to disk. This ensures that whenever the select lights are off that disk accurately reflects the contents of the Host Buffer. It is thus good practice to remove floppy diskettes from the drives only when the select light(s) are off. This entry will then turn off the floppy drive spindle motor, and, if the Advent Personality Decoder board is not present will deselect the floppies so that the select light goes off. If Hard Disks are present then each drive seeks its innermost cylinder and then non existant drive 0 is selected which will turn off the select lights on the drives. 0048 Ten Millesecond Delay -- ENTRY -- A = multiplier for delay EXIT -- none This entry point provides the correct delay regardless of processor clock speed. All Kaypro ROM's assume a 4 MHz clock. In addition, if the keyboard type-ahead is enabled then the keyboard is continually polled during the delay and any keypresses are serviced and placed in the buffer. The accuracy of this timer is within 4%, note that it reflects the effective CPU speed at cold boot and if the speed is changed (as is possible with some speed up modifications) the timing will no longer be accurate. (# New Entry Points available in TURBO ROM) 004B Serial Printer input status -- ENTRY -- none EXIT -- A = 00 and Z if no character ready = FF and NZ if character ready This entry allows use of the extra serial printer port on 84 machines. On 83 ROMs this entry is double mapped to the serial data port. 004E Serial Printer port input -- ENTRY -- none EXIT -- A = character recieved 0051 Serial Printer port output -- ENTRY -- C = character to be sent EXIT -- none 0054 Serial Printer output status -- ENTRY -- none EXIT -- A = 00 and Z if not ready = FF and NZ if ready for next 0054 Reload System -- ENTRY -- DE = Address to load system tracks B = number of sectors to load C = starting sector to load A = logical drive to load from EXIT -- none, any errors force cold boot This entry point will reload all or part of the operating system from the system tracks of the specified drive. The usual conditions of 40 sectors/track will cause floppy type load and > 55 sectors/track will cause RAMDISK or Hard disk reload. 005A Next Screen Dump Character -- ENTRY -- C = FF if first screen character EXIT -- A = character (masked with 7FH) L = column (00 means new line) Z flag set if end of screen This entry allows external programs to read the screen whether this is an 84 or 83 machine. The flashing attirbute on the 83 machines is removed and on 84 machines all pixel graphics are replaced with blanks. It is the responsibilty of the calling program to insert new line characters if needed. 005D Set Cursor Type --- ENTRY -- A= cursor definition EXIT -- none This entry is machine dependent. On 83 mahines the definition is simply the character itself (with or without the hi bit set for flashing). On 84 machines the definition character has the same meaning as the "n" used in the ESC U n cursor setting sequence. 0060 One Millesecond Delay -- ENTRY -- A=delay multiplier EXIT -- none See description of Ten Millesecond above. 0063-6A on 83 machines are not to be used. These are used internally by the ROM initialization code and will have unpredictable results if called by external routines. -- 84 machines only --- All the entry points below have the same parameter interface ENTRY -- none EXIT -- H = BCD hours L = BCD minutes 0067 Kaypro Clock -- Returns current time from built-in Kaypro clock 006A Advent Products Clock -- Returns current time from Advent clock 006D Kenmore Z- TIME Clock -- Returns current time from Kenmore clock NOTE: Clock must exist as no internal checking is done, and unpredictable results are possible if wrong clock is read. r itself (with or without the hi bit set for flashing). On 84 machines the definition character has the same meani