Can I use any ASCII keyboard with an Apple-1?
In the Apple-1 Operating Manual, Wozniak indicates that any ASCII keyboard could be used with his Apple-1.
But in reading the posts in Applefritter and doing some reseach, it seems to me that most people use Datanetics, Amkey, or modified early Apple II keyboards with Apple-1s.
Is there something special on the encoder or to anything else in these keyboards that make them usable with an Apple-1?
If not, then I could use any ASCII-compliant keyboard, such as a TI-99 computer one.
I do not remember if the Apple-1 required 8-bit or 7-bit ASCII; but I am willing to place a bet on 7-bit.
The Apple II uses a dumb keyboard. This was probably done to same money. To use an Apple II keyboard; you will need to design hardware that scans the keyboard matrix and then does the ASCII encoding.
Just purchase a parallel ASCII keyboard.
Or Mike Willegal makes a great ps/2 to parallel keyboard adapter. Then you can just get a ps/2 keyboard.
I checked my old note books and found this:
14 - Strobe
5 - B1
4 - B2
3 - B3
2 - B4
6 - B5
7 - B6
8 - B7
9 - Gnd
16 - +5
This means that the Apple-1 uses 7-bit ASCII. You only need to use data-0 to data-6 from the parallel keyboard. The data-7 line is not needed because it applies to extended ASCII.