| Pin |
Symbol |
Description |
| 1 |
D2 |
Data Line 2 To CPU (Bi-Directional) |
| 2 |
D7 |
Data Line 7 To CPU (Bi-Directional) |
| 3 |
D6 |
Data Line 6 To CPU (Bi-Directional) |
| 4 |
CE
|
Chip Enable Input (Active Low) |
| 5 |
C/D
|
Control/Data Select (High = Ctrl, Low = Data) |
| 6 |
B/A
|
Port A or B Select (Low = A, High = B) |
| 7 |
PA7 |
Peripheral Port A Line 7 (Bi-Directional) |
| 8 |
PA6 |
Peripheral Port A Line 6 (Bi-Directional) |
| 9 |
PA5 |
Peripheral Port A Line 5 (Bi-Directional) |
| 10 |
PA4 |
Peripheral Port A Line 4 (Bi-Directional) |
| 11 |
GND |
Power Ground |
| 12 |
PA3 |
Peripheral Port A Line 3 (Bi-Directional) |
| 13 |
PA2 |
Peripheral Port A Line 2 (Bi-Directional) |
| 14 |
PA1 |
Peripheral Port A Line 1 (Bi-Directional) |
| 15 |
PA0 |
Peripheral Port A Line 0 (Bi-Directional) |
| 16 |
ASTB
|
Port A Strobe Input from Peripheral (Active Low) |
| 17 |
BSTB
|
Port B Strobe Input from Peripherial (Active Low) |
| 18 |
ARDY |
Register A Ready Output (Active High) |
| 19 |
D0 |
Data Line 0 To CPU (Bi-Directional) |
| 20 |
D1 |
Data Line 1 To CPU (Bi-Directional) |
| 21 |
BRDY |
Register B Ready Output (Active High) |
| 22 |
IEO |
Interrupt Enable Output (Active High) |
| 23 |
INT
|
Interrupt Input (Active Low) |
| 24 |
IEI |
Interrupt Enable Input (Active High) |
| 25 |
CLK |
System Clock Input |
| 26 |
+5V |
Power 5V DC |
| 27 |
PB0 |
Peripheral Port A Line 0 (Bi-Directional) |
| 28 |
PB1 |
Peripheral Port A Line 1 (Bi-Directional) |
| 29 |
PB2 |
Peripheral Port A Line 2 (Bi-Directional) |
| 30 |
PB3 |
Peripheral Port A Line 3 (Bi-Directional) |
| 31 |
PB4 |
Peripheral Port A Line 4 (Bi-Directional) |
| 32 |
PB5 |
Peripheral Port A Line 5 (Bi-Directional) |
| 33 |
PB6 |
Peripheral Port A Line 6 (Bi-Directional) |
| 34 |
PB7 |
Peripheral Port A Line 7 (Bi-Directional) |
| 35 |
RD
|
Read Request Input from CPU (Active Low) |
| 36 |
IORQ
|
Input/Output Request Input from CPU (Active Low) |
| 37 |
M1
|
Machine Cycle 1 Input from CPU (Active Low) |
| 38 |
D3 |
Data Line 3 To CPU (Bi-Directional) |
| 39 |
D4 |
Data Line 4 To CPU (Bi-Directional) |
| 40 |
D5 |
Data Line 5 To CPU (Bi-Directional) |