IBM AT emulation

• 80386 SX @ 16 / 20 / 25 MHz (32 bit internally, 16 bit external bus)
• optional 80387 FPU
• sixteen ZIP sockets accept up to 8 MB RAM
• 1 MB factory installed
• supports 256k×4 or 1M×4 page mode ZIPs, 80-120 ns or faster
• accepts ZIPs in groups of four
• 64 kB AT compatible BIOS
  • upgrading the BIOS and fitting a ZIP to SIMM converter makes possible to use 16 MB RAM
• 128 kB dual-port RAM for data exchange between the BridgeBoard and the Amiga
• can use a PC hard disk (with additional ISA controller), virtual drives on Amiga partitions (hardfiles), you can even have an Amiga partition on the PC hard drive
• PC floppy drives can be used in an internal bay, Amiga floppy drives can be used as PC only or shared, external Amiga drives can be connected directly to DB23 floppy connector of the BridgeBoard
• only two floppy drives are accessible by the BridgeBoard
• the Amiga supports MDA (monochrome) and CGA modes through the native display (CGA 640x200x2 or 320x200x4 modes) – you can toggle between Amiga and PC screens
• with an ISA VGA board a separate monitor is needed
• the card uses the Amiga’s serial or parallel ports for printing
• for modems it can only use an internal ISA modem or serial card
• PC beeper on board
• much slower than a PC with the same processor
• card occupies 512kB in the Zorro II address space – when installed, only 7.5 MB of the address space is left for other expansion cards

Notes