Pin assignments of SCSI connecter
| Internal (50 pins) | External(25 pins) | Signal name | Detail |
| 2 | 8 | /DB0 | Bit 0 of SCSI data bus |
| 4 | 21 | /DB1 | Bit 1 of SCSI data bus |
| 6 | 22 | /DB2 | Bit 2 of SCSI data bus |
| 8 | 10 | /DB3 | Bit 3 of SCSI data bus |
| 10 | 23 | /DB4 | Bit 4 of SCSI data bus |
| 12 | 11 | /DB5 | Bit 5 of SCSI data bus |
| 14 | 12 | /DB6 | Bit 6 of SCSI data bus |
| 16 | 13 | /DB7 | Bit 7 of SCSI data bus |
| 18 | 20 | /DBP | Parity bit of SCSI data bus |
| 20 | - | N.C. | Not connected |
| 22 | - | N.C. | |
| 24 | - | N.C. | |
| 26 | 25 | TPWR | +5V terminal power |
| 28 | - | N.C. | |
| 30 | - | N.C. | |
| 32 | 17 | /ATN | Attention |
| 34 | - | N.C. | |
| 36 | 6 | /BSY | Bus busy |
| 38 | 5 | /ACK | Handshake acknowledge |
| 40 | 4 | /RSR | Bus reset |
| 42 | 2 | /MSG | Message phase |
| 44 | 19 | /SEL | Select |
| 46 | /C /D | Control or data on SCSI bus | |
| 48 | /REQ | Handshake request | |
| 50 | /I/O | Controls the direction of data movement | |
| All odd pins | 7,9,14,16,18 and 24 | GND | Ground |