SCSI to MFM/RLL schematic
cclist at sydex.com
Sun Nov 28 17:46:56 CST 2010
On 28 Nov 2010 at 22:50, Phill Harvey-Smith wrote:
> Does anyone happen to have the schematic of one of the SCSI->MFM/RLL
> boards ? I have the Adaptec ACB-4000 and Xebec S1410A board documents
> from bitsavers but thy only have the schematics for the computer end.
> All the talk of interfacing to SCSI has got me wanting to have a go
> :) I'm just want to look and see how it was done in the olden
> days....failing that I guess I'm gonna have to start tracing
I've got a couple of the OMTI 3127 RLL-to-SCSI converters. They
basically have the OMTI RLL hard disk controller, a Z8 MCU, some
EPROM, RAM and an NCR-licensed SCSI bus interface chip.
Another example of SCSI-to-something else can be found in the various
tape drive interfaces. Cipher used an 80188 and an NCR SCSI
interface for their M990 tape streamer (the drive controller itself
is a Z8002 MPU).
You can see a similar pattern in scanners and the like--an MPU, some
ROM, some RAM and a bus interface chip.
If I were to make a SCSI hard disk substitute today, I'd probably use
an ARM M3 with external RAM interface (for cache), some SRAM, an
SDHC for storage and whatever I could find for a bus interface IC.
On the other hand, SCSI-to-USB may be a more logical choice, given
the wider range of USB devices available.
More information about the cctech