A4091 / ReA4091

Description

Please note that you need a Super Buster 11 chip in your Amiga 3000(T) and A4000(T) for the A4091 to function properly.

The A4091 is a full-length Zorro-III DMA Fast SCSI-II hard drive controller designed for the Amiga 3000(T) and A4000(T). It is based on the NCR 53C710 chip. The A4091 package includes an active terminator.

This new edition of the A4091, called the ReA4091 has additional features and bug-fixes over the original A4091. The key features are:

• Fast SCSI-II (10MB/s max) controller for Amiga Computers
• One of only two Zorro-III SCSI controllers ever designed
• Full-length Zorro-III with DMA
• Designed for the Amiga 4000; works in the Amiga 3000 (but please check the note below!)
• Requires Super Buster 11
• Based on NCR 53C710 chip
• Reproduction based on an old board and PAL source code released as part of the Dave Haynie Archives.
• 80 components on the top; 147 components on the bottom
• The ReA4091 has been fully open sourced. Check out the ReA4091 GitHub project
• Two versions: ReA4091 and the shorter ReA4091 Mini to keep your ISA/PCI slots available.
• Modern Autoboot ROM (Open Source!)
  • TD64 and NSD64 support for hard disks larger than 4GB
  • Early Boot Diagnostics menu (press right mouse button during boot)
  • CDROM boot support
  • Also works on original A4091 boards

Important note for Amiga 3000 users:

The A4091 will not solve any SCSI hang-ups on Amiga 3000 upgraded with 68040/68060 processor boards. To solve these SCSI problems, you will definitely need to upgrade your Amiga 3000’s DMAC chip. Please keep track of the fabulous project called ReSDMAC. It’s a great effort to replace the buggy DMAC revision 2 chip with a revision 4 variant.

Credits

Many thanks to Stefan Reinauer and Chris Hooper for their tremendous efforts!