TRS80 Model III Keyboard on my 6502 SBC

The time has come to add a keyboard. I scrounged up an old Radio Shack TRS-80 Model III last year. Alas, it arrived broken. The tube was completely smashed! Thanks, UPS! So I decided to repurpose the microcomputer to become my future casing for the 6502 SBC. Not sure what I'm going to do for the final display. I did get my hands on some TMS9918 chips and the Parallax Propeller. But that's another post for another time.

For now, the keyboard circuit is all done. It's fairly simple and the 8x8 keyboard matrix is directly connected to port A and port B of a second VIA chip. It did take me a while to map out the keyboard matrix. What is need about this keyboard is the integrated reset button.

TRS-80 Model III Keyboard Matrix
12KE010C (or is it I2KEOIOC ?) ALPS ELECTRIC CO., LTD. JAPAN
20 pin connector
	9	10	11	12	13	14	15	16
1	@	A	B	C	D	E	F	G
2	H	I	J	K	L	M	N	O
3	P	Q	R	S	T	U	V	W
4	X	Y	Z
5	0	1	2	3	4	5	6	7
6	8	9	: *	; +	, <	- =	. >	/ ?
7	Enter	Clear	Break	Up	Down	Left	Right	Space
8	L-Shift	R-Shift
Reset	18	Normally Closed
	19	Common
	20	Normally Open