Problems with 8/A Programmer's Panel

Johnny Billquist bqt at
Wed Sep 9 04:21:28 CDT 2015

On 2015-09-09 01:07, Charles wrote:
> Several years ago, Vince Slyngstad and I "cloned" the rare DKC8-AA
> Programmer's Panel for PDP-8 with some improvements (0.6 vs. 0.3" LED
> displays, real "click" buttons instead of that membrane keypad, and
> fixed a couple of bugs in the original design). Also, since 8235's were
> scarce even then, we used 74F244 buffers instead to gate the input vs.
> output of the switch register onto the bus back to the M8316 Option 1
> board.

Not sure what you mean by membrane keypad. My front panels certainly 
have real buttons, which makes a clicking noise and feeling when I press 
them. But maybe I'm confused and there is some membrane behind the keys 
or something?


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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