Introduction
When
I got my Personal Iris 4D/25, I had no
keyboard for this machine. Unfortunately it needs a special keyboard
with a DB9 male connector - it's not just a different connector,
the communication protocol of the keyboard also differs from standard
PS/2 or AT keyobards. But luckily I own an SGI
Indigo 1 including a keyboard. This keyboard uses the same
protocol as the one of many other old SGI machines, but has a
different connector (it has a Mini-DIN-6 connector like a PS/2
keyboard). So I had to build an adaptor.
Pinouts of the Indigo Keyboard
Pin |
Description |
1 |
K_TXD/K_RXD |
2 |
M_TXD/M_RXD |
3 |
Ground |
4 |
+12 |
5 |
K_RXD/K_TXD |
6 |
-12 |
|
 |
 |
Pinouts of the Personal Iris Keyboard
Pin |
Description |
1 |
Ground |
2 |
K_TXD/K_RXD |
3 |
Ground |
4 |
-12 |
5 |
M_TXD/M_RXD |
6 |
Ground |
7 |
+12 |
8 |
K_RXD/K_TXD |
9 |
Ground |
|
 |
 |
Pinout of even older SGIs
Pin |
Description |
1 |
Ground |
2 |
Ground |
3 |
Ground |
4 |
K_RXD/K_TXD |
5 |
K_TXD/K_RXD |
6 |
N/C |
7 |
+12 |
8 |
+12 |
9 |
+12 |
10 |
M_TXD/M_RXD |
11 |
Reserved |
12 |
Reserved |
13 |
N/C |
14 |
N/C |
15 |
-12 |
|
 |
Pinout of Converter Cable
Knowing the pinouts of the connectors, an adaptor cable can be
assembled using 6 wires, one DB9 male connector and one Mini DIN6
female connector with the following table:
DB9 Pin |
Description |
DIN6 Pin |
1 |
Ground |
NC |
2 |
K_TXD/K_RXD |
1 |
3 |
Ground |
NC |
4 |
-12 |
6 |
5 |
M_TXD/M_RXD |
2 |
6 |
Ground |
3 |
7 |
+12 |
4 |
8 |
K_RXD/K_TXD |
5 |
9 |
Ground |
NC |
|
My converter cable looks this
simple:  |
If you even don't have an Indigo Keyboard
Then there is still a chance: There exists a tutorial
how to build a cnoverter for the SGI Indigo to plug in standard
PS/2 keyboards and mice. But this one is far trickier.
|