C16/Plus4 Expansion Bus

Pinout

Available on Commodore C16, C116 and +4 computers.

50 PIN FEMALE EDGE (2 mm pitch) at the Computer.

Pin	Name	Description
1	GND	Ground
2	+5V	+5 VDC
3	+5V	+5 VDC
4	/IRQ	Interrupt
5	R/W	Read/Write (1=Read, 0=Write)
6	C1HIGH	External Cartridge Chip Selects C1 High
7	C2LOW	External Cartridge Chip Selects C2 Low (reserved)
8	C2HIGH	External Cartridge Chip Selects C2 High (reserved)
9	/CS1	Chip Select Line 1
10	/CS0	Chip Select Line 0
11	/CAS	Column Address Strobe
12	MUX	DRAM address multiplex control signal
13	BA	Bus Available (Low=DMA)
14	D7	Data 7
15	D6	Data 6
16	D5	Data 5
17	D4	Data 4
18	D3	Data 3
19	D2	Data 2
20	D1	Data 1
21	D0	Data 0
22	AEC	Address Enable Code
23	EAI	External Audio In
24	PHI 2	Artificial Phi 2 signal
25	GND	Ground
A	GND	Ground
B	C1LOW	External Cartridge Chip Selects C1 Low
C	/RESET	Reset
D	/RAS	Row Address Strobe
E	PHI 0	Artificial Phi 0 Signal
F	A15	Address 15
H	A14	Address 14
J	A13	Address 13
K	A12	Address 12
L	A11	Address 11
M	A10	Address 10
N	A9	Address 9
P	A8	Address 8
R	A7	Address 7
S	A6	Address 6
T	A5	Address 5
U	A4	Address 4
V	A3	Address 3
W	A2	Address 2
X	A1	Address 1
Y	A0	Address 0
Z	n/c	Not connected
AA	n/c	Not connected
BB	n/c	Not connected
CC	GND	Ground

PHI 2: Address valid on the rising edge, data valid on the falling edge

Usenet posting in comp.sys.cbm, Pinout specs for cbm machines needed by Lonnie McClure
SAMS Computerfacts CC8 Commodore 16
Article in C'T September 1986