Dave's Dev Lab-
Introduction to the WITCH-E Project
02/22/2017 at 01:00 • 0 comments -
Keypad Encoder
02/22/2017 at 00:38 • 0 commentsKeypad Encoder
Using basic diode steering, the keypad inputs are encoded to a 5-bit Baudot Code like code. The one that is used on the original WITCH is a variation of the standard Baudot code which was modified to make encoding of math operations easier. I could have made this board a lot smaller using some surface mounted device (SMD) diodes, but I had this vintage box of Texas Instruments 1N916A switching diodes that I thought would look nice to use. The date code on the box seems to indicate the middle of August 1970 as the production date....
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Manual Entry Keypad
02/22/2017 at 00:25 • 0 commentsManual Entry Keypad Assembled
Slowly moving along on WITCH-E... new PCBs arrived today...
The original WITCH has a manual input panel in order to input commands. this is manual for testing and selecting control of which tape readers to start executing from. For WITCH-E it is an intermediate step between having the tape readers working and being able to fully test the system... next board to be assembled is the keypad encoder which will take the keypad input and cover it to a 5-bit baudot like encoding...
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WITCH-E Decimal Based Computer
Document and create a modern replica of the Harwell Dekatron computer known as the WITCH
