Hey, the Spuds for the ZX80 & ZX81 have found their way here
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Do we need a driver board to repeat (amplify) the signals? https://sinclairzxworld.com/viewtopic.php?f=7&t=281&p=2046&hilit=spectrum+keyboard#p2046 Not if the wiring is kept as short as possible. If you do want longer wiring, or want to use a multicore cable, then it's the address lines that need b...
- Mon Feb 12, 2018 1:12 am
- Forum: Hardware
- Topic: My first wire wrap: Wilf's AT keyboard interface
- Replies: 43
- Views: 1446
The keyboard uses the Z80's I/O instructions. It is documented (but only in some of the Z80 documentation) that when an I/O instruction puts an address on address bus lines A0 to A7, it also puts a value on address lines A8 to A15. What is put on these depends on the instruction. For example: IN A,(...