Cyberamic control computer lights board

The last board variant I have done is the 0021 lights board. Architecturally this is very similar to the character board, but even from the earliest variant this board never had audio functionality. That means the designers used all 16 outputs from the PIA on this card to drive 24v controlled lights.

The lion’s share of 0021 rev.a is shared with the character card, in fact even the chip locations are shared with 0004 rev.b. If you look at the two unused chip locations on this board, they used to be populated on the character card. The upper one does not have power to it because it was originally an op-amp chip and did not have power on the diagonal opposite pins. The power that did run there was 12v and -12v and that is now gone.

This is the modification for this card to give it 16 outputs. We now use two of the open collector outputs from the 7406 instead of adding another uln2003. That means these outputs are not as powerful, but I think the lights were relay controlled so in this case the high current is not as needed.

The final board is 0021 rev.f, and I think that naming is probably misleading. This board is part of the post-1993 redesign so it is based off the 0034 rev.e. I think these boards were designed at the same time because 0034 rev.e changes the DIP resistor packs to be 7 resistors per for LEDs and then those two remaining resistors are used on 0021 rev.f. This board includes all the changes from 0034 rev.e except it removes the jumpers for 5v/24v. These boards were never used to drive something like the A/V switcher, so that’s not needed.

That’s it for all the boards I have re-made in KiCAD. If you want a lights board there is no functional difference between rev.a and rev.f. They both have the same electrical interface, they fit the same connector, and all software that talks to one talks to the other. I have the boards up here on github, but feel free to ask me about any issues you may have with one of these setups. I may know something after digging so deep into all this.