| Pin number | Signal description |
| 1 | Handshake output |
| 2 | Handshake input |
| 3 | Transmit data * |
| 4 | Ground |
| 5 | Receive data * |
| 6 | Transmit data + |
| 7 | General-purpose input |
| 8 | Receive data + |
| 9 | +5 volts |
| Pin number | Name | Description |
| 1 | ADB | Bidirectional data bus used for input and output. It is an open-collector signal pulled up to +5 volts through a 470-ohm resistor on the main logic board. |
| 2 | PSW | Power-on signal that generates reset and interrupt key combinations |
| 3 | +5V | +5 volts from the computer. |
| 4 | GND | Ground from the computer. |
| Pin Number | Signal Name | Singnal Description |
| 8 | /DB0 | Bit 0 of SCSI data bus |
| 21 | /DB1 | Bit 1 of SCSI data bus |
| 22 | /DB2 | Bit 2 of SCSI data bus |
| 10 | /DB3 | Bit 3 of SCSI data bus |
| 23 | /DB4 | Bit 4 of SCSI data bus |
| 11 | /DB5 | Bit 5 of SCSI data bus |
| 12 | /DB6 | Bit 6 of SCSI data bus |
| 13 | /DB7 | Bit 7 of SCSI data bus |
| 20 | /DBP | Parity bit of SCSI data bus |
| 25 | n.c. | Not connected |
| 25 | TPWR | +5 V terminator power |
| 17 | /ATN | Attention |
| 6 | /BSY | Bus busy |
| 5 | /ACK | Handshake acknowledge |
| 4 | /RST | Bus reset |
| 2 | /MSG | Message phase |
| 19 | /SEL | Select |
| 15 | /C/D | Control or data |
| 1 | /REQ | Handshake request |
| 3 | /I/O | Input or output |
| 20, 22, 24, 28, 30, 34, and all odd pins except pin 25, 7, 9, 14, 16, 18, and 24 | GND | Ground |
| Pin number | Signal name | Description |
| 1 | RED.GND | Red video ground |
| 2 | RED.VID | Red video signal |
| 3 | /CSYNC | Composite synchronization signal |
| 4 | SENSE0 | Monitor sense signal 0 |
| 5 | GRN.VID | Green video signal |
| 6 | GRN.GND | Green video ground |
| 7 | SENSE1 | Monitor sense signal 1 |
| 8 | n.c. | Not connected |
| 9 | BLU.VID | Blue video signal |
| 10 | SENSE2 | Monitor sense signal 2 |
| 11 | GND | CSYNC and VSYNC ground |
| 12 | /VSYNC | Vertical synchronization signal |
| 13 | BLU.GND | Blue video ground |
| 14 | HSYNC.GND | HSYNC ground |
| 15 | /HSYNC | Horizontal synchronization signal |
| Shell | SGND | Shield ground |