NeXT
Veteran Member
Yes. The parallel port does operate and is completely functional with the resistors removed and the cuts repaired.
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Modified Lisa Backplane
- Thread starter NeXT
- Start date
stepleton
Veteran Member
As you said the signals were going through the resistors, I'm guessing that they may have been installed as series termination to attenuate reflections on the parallel port lines. I've done a similar same thing with that goal in mind, albeit on the device end, in a ProFile emulator, and not by hacking up a Lisa motherboard.
Pin 13 is data bit 7, the highest-order bit (counting up from 0). I have no idea why you would ever want to cut it.
Maybe this Lisa was sending signals down a long parallel cable, and whatever equipment receiving it couldn't handle 8-bit bytes? It's pretty odd.
Pin 13 is data bit 7, the highest-order bit (counting up from 0). I have no idea why you would ever want to cut it.
Maybe this Lisa was sending signals down a long parallel cable, and whatever equipment receiving it couldn't handle 8-bit bytes? It's pretty odd.