Binary keypad front panel

ben bfranchuk at
Fri Mar 3 16:11:21 CST 2017

On 3/3/2017 12:58 PM, John Wilson via cctalk wrote:
> I made this as a joke, but also as a simple test device for a NatInst
> PCI-DIO-96 GPIO card I was writing a driver for:
> It occurred to me that lots of old machines had binary front panels
> (switches and lights) and lots of machines had keypad front panels (octal
> or hex, with 7-segment LEDs), but I'd never seen a binary keypad front
> panel.  Plus I wanted to experiment with Cherry MX keyswitches, and try out
> wasdkeyboards's custom keycaps (but they're $7/ea so I didn't want to try
> anything too big the first time).  That plus two 74LS132s, four 74LS240s,
> and two 74LS273s, discrete stuff and cabling, and a PCI-DIO-96 that was
> $25 on eBay, and it works.
> "set dr dio96:" in the DOS and stand-alone versions of E11 V7.3 makes it
> (or anyone else's homemade doohicky) appear at 777570 as usual (or you can
> add "set dr r0" to get the R0-during-WAIT display like on a PDP-11/70 --
> whatever your OS's NULJOB uses).  I'd give Gerbers to anyone who cares
> but really it's just a dumb joke.  Fun one though.
> John Wilson
> D Bit

Use a TELEPHONE keypad 0-7 OCTAL 8 and 9 binary. :)

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