A2386SX Bridgeboard Information


        
Jumper Information.

    J101: (ON) Enables Pipeline mode. If removed, Pipeline mode is disabled.

    J501, J502: (1-2) Select the type of internal drive. Pins 1-2 for PC drives, Pins 2-3 for Amiga.
                      Both jumpers must be set the same.

    J506: (ON) Enabled on-board PC floppy drive access. If removed, the floppy drive controller DMA
               is disabled.

    J515: (1-2) Select which Amiga drive is used as the shared drive. Pins 1-2 for DF0,
                Pins 2-3 for DF1

    J601: (ON) Enables on board PC floppy drive access. 

Default positions in parentheses. The user should only need to change J501, J502 and J515.


Expansion Issues:

Here are memory locations, I/O ports and interrupts to avoid when adding PC peripherals.

Memory Locations to avoid:

 A0000 to AFFFF: If Janus handler load segment is set to A0000 in PCPrefs.
 B0000 to B1FFF: If Monochrome display adapter emulation is enabled in PCPrefs.
 B8000 to BFFFF: If Color display adapter emulation is enabled in PCPrefs.
 D0000 to DFFFF: If Janus handler load segment is set to D0000 in PCPrefs.

I/O Ports to avoid:

 000-00F            0F0
 0C0-0DE            0F1
 060                0F4
 061                0F5
 062                0F8-0FE
 064                2Fx
 070                37x
 087-08F            3Bx      If MDA emulation is enabled.
 092                3Dx      If CGA emulation is enabled.
 0E8-0EF            3F0-3F7  If on-board floppy access is enabled.

Interrupts to avoid:

 IRQ0
 IRQ1
 IRQ2
 IRQ3
 IRQ6  If on-board floppy access is enabled.
 IRQ7
 IRQ8
 IRQ13

Technical Specifications:

    Function: Provides an IBM-PC/AT compatible coprocessor system for a computer in the A2000, A3000
         and A4000 series.

    Processor: 80386SX

    Clock Speed: 16MHz, 20MHz or 25MHz

    Coprocessor: Optional 80387SX FPU supported

    Memory: 1MB supplied (expandable to 8MB) (possible A2386SX Memory Configurations)

    Memory type: uses 1MB x 4 or 256K x 4 ZIP chips. Recommended speeds are 80ns or faster for
                 20MHz or 25MHz models, 100ns or faster for 16MHz models

    Floppy Disks: Supports up to 2 floppy disk drive from the following:

      1. One PC-only external drive (3.5" or 5.25") using Amiga compatible external floppy port.

      2. Two PC-only internal drives of same computer type (PC or Amiga), 3.5" 1.44MB PC drive, 3.5"
         720KB/880KB PC or Amiga drive, 3.5" 880KB/1.76MB dual-speed Amiga drive, 5.25" high density,
         or 5.25" low density.

      3. One shared 3.5" Amiga drive (except in A4000T - see Common Problems and Questions)

    Card Type: Uses both Amiga bus and PC ISA bus. Occupies one of the two combined positions.

    Video Display:

      1. IBM-PC/AT MDA Monochrome 80x25 text mode.

      2. IBM-PC/AT CGA Color text (80x25 & 40x25) and graphics (640x200x2 & 320x200x4 color) modes 
         supported in Amiga windows simultaneously.

    Keyboard: IBM-PC/XT keyboard emulation using the Amiga keyboard

    Parallel Port: IBM-PC/AT compatible Centronics port emulation using the Amiga's parallel port.

    ROM: 64KB AT-compatible BIOS (A2386SX Bridgeboard Setup)

    Interprocessor Communications: 128K of shared memory, ability for PC to interrupt Amiga and 
                                   vice versa.

    Power: 2.5 amps @ 5.0V