A2091 rev 4.1
Company
Commodore, USA |
Date
1991 |
Amiga
A2000, A3000, A4000 |
Interface
Zorro II |
Autoconfig ID
514 / 2,3,10 |
SCSI controller
- Western Digital 33C93
- uses the same DMAC custom chip for DMA transfers as the A3000
- knows the Rigid Disk Block and SCSI Direct protocols
- built in XT IDE (8 bit) hard disk controller – the connectors and LED are not installed but their place is visible on the card
- 50 pin internal SCSI header
- DB25 external connector
- a 3.5″ hard disk can be mounted on the card
- 16 kB autoboot ROM (can be disabled) – autobooting requires at least Kickstart 1.3
- revision 7.0 of the ROM is necessary for 68040 machines
- supports SCSI network sharing
- supported by Linux, NetBSD and OpenBSD
- A-Max II driver (scsi.amhd)
memory
- sixteen DIP sockets accept 0.5, 1 or 2 MB RAM
- supports 256k×4 (44256) chips, 120 ns or faster
- cannot use DMA to transfer data to 32 bit fast RAM
- if Zorro II DMA memory is not available the driver falls back to programmed I/O transfers
- performs extremely slow in the A4000 because of the above mentioned two problems
recapped with Rubycon brand 105° type