Amiga Hardware DatabaseCompany Norman Jackson / MegaMicro, Australia | Amiga A500 | Interface side expansion port | Autoconfig ID 4096 / 3,4 |
- SCSI + RAM for A500, a public domain kitware project
- schematics, building instructions and driver software are all published
- custom logic (GALs, PALs, etc.) are not published, these chips have to be ordered from the author
- the four custom logic chips:
- Bertie - controls the memory autoconfigure logic
- Cyril - 8 bit SCSI autoboot controller chip
- Griswold - master timing controller for the DRAMs
- Humphrey - controls RAM operation
- SCSI controller
- National Semiconductor DP8490V SCSI controller IC - an enhanced version of NCR 53C80
- autoboot ROM - autobooting requires Kickstart 1.3
- autoboot disable switch for older Kickstarts or for game compatibility
- supports the Rigid Disk Block standard
- external DB25 SCSI connector
- SCSI access LED
- termination power option - jumper selectable +5V on pin 25 for using passive terminator
- non-DMA transfer
- custom synchronising logic
- memory
- 16 ZIP sockets accept up to 8 MB RAM
- takes 256k×4 or 1M×4 ZIPs
- ZIP sizes cannot be mixed
- possible configurations are 0, 2, 4 or 8 MB
- static column ZIPs work, but not improve performance
- zero wait state
- RAM access LED
- autoconfigure LED
- notes
- connects to the side expansion port
- passthrough connector is optional
- the case is wide enough for a companion board, the SCRAM-Jet - a 030 accelerator with 32 bit RAM, but it was never published
- works with the A1000
- SCRAM500.lzh
building instructions, schematics
user manual
driver software
676 kB
Advert (AU)
1991-12
Advert (AU)
1992-06