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PDP-8/S Computer
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Here are some pictures of the PDP-8/S:
Like much of the stuff described on this site, this isn't working.
When I got it, one of the flip-chips had been removed, and was suspected
of not working:
Indeed, inspection revealed a problem:
After fixing that, I did some checkout of the power supply, reforming
the capacitors and determining that it was safe to power the machine.
With the machine powered up, it didn't take long to discover that the
bad card wasn't the only problem. Pressing LA and such doesn't accurately
copy the contents of the switch register to MA.
The 8/S is a serial machine, so it actually takes many clocks of the
shift registers even for such a simple operation. My next step will be to
check the power supply for ripple, then check the internal clocking to see
why it isn't reliable.
It came with a PT08 terminal controller and various extra flip-chips,
shown here piled on and around the machine:
The PT08 is necessary because it was not possible at the time to get
both the terminal controller and the CPU to fit into the nice desktop box.
Each PT08 controls a single serial terminal, usually an ASR33 with reader-run
control and interfaced with current loops.
Last updated on 02/25/23 02:21 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
