Thanks trag! Might the 53CF96 be a drop in rework replacement for the 53C96 on a 7100 board that might just work or is there a lot of othe junk on that second bus?
EveryMac lists my 81/110 as Fast SCSI, I'll have to check the boards? Doesn't matter, I've got the JackHammer/Studio Array, but I'm curious about what they did.
The 7100 only has the single slow bus. Only the 8100 and 9150 had two SCSI busses.
On the entire X100 family, the boring SCSI is in the AMD AM79K950 (? think the first two digits might be wrong but its the only big AMD chip) CURIO chip. There's no replacing the SCSI chip because it's embedded in taht much larger chip that does serial and ethernet as well. The 8100 and 9150 add a discrete 53CF96 for the separate Fast SCSI bus.
This model is also used on teh X500/X600 family, except, every member of that family has the second Fast bus, but not the 7200... EveryMac must be referring to just the extra internal-only bus, or it's wrong.
Apple started using CURIO (custom chip from AMD encompassing serial, SCSI, enet) in the Quadra AVs and continued through the end of the x600 family. Didn't change until Beige came out.
There was a lot of confusion when SCSI II was codified. The SCSI II standard is the one that introduced Fast and Fast & Wide SCSI, and lots of folks started calling things that newly met the SCSI II standard, "Fast SCSI" even though they just met the 5 MB/s SCSI II standard. They did not implement the optional 10 MB/s protocol. True, SCSI II was faster than what came before, but not all SCSI II is Fast SCSI II.
The 81/110 is just like the 8100. Exactly the same down to the tiny SM resistors. The only difference is the video out connector.