CoCo and Dragon keyboard matrix

One of the only hardware differences between the Tandy Color Computer and the Dragon32/64 is that of the physical keyboard wiring. An adapter can be made to wire between the two, allowing the use of a Dragon keyboard on a CoCo and vice-versa. The rewiring modifies the bottom 7 pins of the keyboard connector, with the bottom 5 pins of the CoCo shifted up by 2 pins for the Dragon:

	Pins
Dragon	6	7	1	2	3	4	5	8	9	10	11	12	13	14	15	16
CoCo	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16

The resulting keyboard matrix for each machine is:

Tandy Color Computer - CoCo

		Row (PIA0 $ff00)
Column (PIA0 $ff02)		0	1	2	3	4	5	6	7
	0	@	A	B	C	D	E	F	G
	1	H	I	J	K	L	M	N	O
	2	P	Q	R	S	T	U	V	W
	3	X	Y	Z	Up	Dwn	Lft	Rgt	Spc
	4	0	1	2	3	4	5	6	7
	5	8	9	:	;	,	-	.	/
	6	Ent	Clr	Brk					Shft
	7	Comparator input

Dragon32/64

		Row (PIA0 $ff00)
Column (PIA0 $ff02)		0	1	2	3	4	5	6	7
	0	0	1	2	3	4	5	6	7
	1	8	9	:	;	,	-	.	/
	2	@	A	B	C	D	E	F	G
	3	H	I	J	K	L	M	N	O
	4	P	Q	R	S	T	U	V	W
	5	X	Y	Z	Up	Dwn	Lft	Rgt	Spc
	6	Ent	Clr	Brk					Shft
	7	Comparator input

See also

• Dragon32/64 detailed memory map