10base2 / 10baseT (again)

From: Eric J. Korpela <korpela_at_ellie.ssl.berkeley.edu>
Date: Tue Nov 28 14:08:26 2000

> > Try to plug in a device with the Future Domain pinout. I don't know
> > which came first, I just know that they are incompatible to the point
> > of releasing the majic smoke.
>
> How strange! I have a Future Domain SCSI card (850-MEX?) that uses
> exactly the Apple pinout, and even carries a sticker on the rear
> bezel stating same!

The fact that there was an earlier Future Domain SCSI pinout is exactly
why there is a sticker pointing out the the newer card has the Apple
pinout. If there weren't another possibility, there wouldn't have been
a need for the sticker.

For example the TMC-850 has the Future Domain pinout and the TMC-850M
has the Apple pinout. I think it's pretty much the same for other
models, an M in the model number means Apple SCSI.

Here's the Future Domain Pinout

     ___________________
     | SCSI | |
     | SIGNAL| DB-25S |
     +-----------------+ DB-25S (female)
     | -DB(0)| 14 | _____________________________
     | -DB(1)| 2 | 13\ o o o o o o o o o o o o o /1
     | -DB(2)| 15 | 25\ o o o o o o o o o o o o /14
     | -DB(3)| 3 | ------------------------
     | -DB(4)| 16 | View from rear of computer.
     | -DB(5)| 4 |
     | -DB(6)| 17 |
     | -DB(7)| 5 |
     | -DB(P)| 18 |
     | GND |1,6,8,13 |
     | GND |13,19,25 |
     | -ATN | 20 |
     | BSY | 23 |
     | -ACK | 22 |
     | -RST | 10 |
     | -MSG | 21 |
     | -SEL | 7 |
     | -C/D | 11 |
     | -REQ | 24 |
     | -I/O | 12 |
     +-----------------+
     Pin 9 is NOT CONNECTED

Here's the Mac Pinout

     ___________________
     | SCSI | |
     | SIGNAL| DB-25S |
     +-----------------+ DB-25S (female)
     | -DB(0)| 8 | _____________________________
     | -DB(1)| 21 | 13\ o o o o o o o o o o o o o /1
     | -DB(2)| 22 | 25\ o o o o o o o o o o o o /14
     | -DB(3)| 10 | ------------------------
     | -DB(4)| 23 | View from rear of computer.
     | -DB(5)| 11 |
     | -DB(6)| 12 |
     | -DB(7)| 13 |
     | -DB(P)| 20 |
     | GND | 7,9,14 |
     | GND |16,18,24 |
     | -ATN | 17 |
     | BSY | 6 |
     | -ACK | 5 |
     | -RST | 4 |
     | -MSG | 2 |
     | -SEL | 19 |
     | -C/D | 15 |
     | -REQ | 1 |
     | -I/O | 3 |
     +-----------------+
     Pin 25 is NOT CONNECTED in the Mac Plus implementation. Newer Macs
     connect TERMPWR to pin 25, but are otherwise the same.
Received on Tue Nov 28 2000 - 14:08:26 GMT