Apollo 7121
Posted: 30 May 2021, 04:27
This is not a particularly nice keyboard to type on.
It uses a Micro Switch Silent Tactile membrane and is 106ST13-2E-J.
This particular board has some scratches.
There were also some broken keys that needed to be glued and even worse some that apparently already had something like that done to them and aren't straight any more.
On boot, it is 1200 baud, even parity, serial ASCII. As described in the Technical Reference, some function keys also send up transitions. But all the shifting is done inside the keyboard.
If that were all, it would end up in that pile with only a TTL serial to USB converter. But, as it turns out, this is only a compatibility mode 0 for use with older computers. It also has a mode 1 where every key sends both down and up transitions. CAPS LOCK is still handled in the keyboard, its up / down code effectively giving the on / off state of the LED. But other than that, there is no translation in this mode.
That is enough for a straightforward converter to USB keyboard.
And I admit that the left-hand navpad with its various kinds of arrow icons still has a cool tail-end of '80s feel from before everything became the same.
It also has a mouse port, which also uses a DE-9 connector, although it isn't a serial mouse. It would be straightforward to include support for this in the converter, but I don't hold out much hope of ever coming across an old Apollo mouse.
How the keyboard accomplishes all this is at once simple and surprising.
- Apollo-case.jpg (368.1 KiB) Viewed 1322 times
- 106ST13-2E-J.jpg (205.61 KiB) Viewed 1322 times
- Apollo-back.jpg (290.15 KiB) Viewed 1322 times
On boot, it is 1200 baud, even parity, serial ASCII. As described in the Technical Reference, some function keys also send up transitions. But all the shifting is done inside the keyboard.
If that were all, it would end up in that pile with only a TTL serial to USB converter. But, as it turns out, this is only a compatibility mode 0 for use with older computers. It also has a mode 1 where every key sends both down and up transitions. CAPS LOCK is still handled in the keyboard, its up / down code effectively giving the on / off state of the LED. But other than that, there is no translation in this mode.
That is enough for a straightforward converter to USB keyboard.
- Apollo-converter.jpg (514.4 KiB) Viewed 1322 times
It also has a mouse port, which also uses a DE-9 connector, although it isn't a serial mouse. It would be straightforward to include support for this in the converter, but I don't hold out much hope of ever coming across an old Apollo mouse.
How the keyboard accomplishes all this is at once simple and surprising.
Spoiler: