Acorn AKA31 SCSI Podule

Register description

IOC Address map :
  0000-1fff - ROM (banked)
  2000 - Interrupt status (read)
    bit 0 - IRQ occurred
    bit 1 - DMA terminal count IRQ
    bit 3 - SBIC IRQ
  2000 - Clear terminal count IRQ (write)
  3000 - Control
    bits 0-5 - page (used for both ROM & RAM)
    bit 6 - IRQ enable
    bit 7 - reset

MEMC Address map :
  0000-1fff - RAM (64kb, banked)
  2000-2fff - WD33C93A SBIC
  3000-3fff - D71071L DMA controller

Basic design

Uses a WD33C93A SBIC to implement SCSI handling. This is connected to the 64kb of onboard RAM via a D71071L DMA controller.

Notes

AKA30/31/32 all appear to be slight variants on the same basic design.

Links

Chris's Acorns: Acorn AKA31 SCSI Podule