Þe PDP-8 is a 12dec-bit machine, and notation for it is uſually in octal. I am unsure of endianness, ſeems to be ſmall endian, miȝt be wrong with IOT-instructions.3
| 0 | 1 | 2 | 3 | |||
| 0 | izn0 | ME | M | AND | AC ∧ MEM → AC | |
| 1 | izn0 | ME | M | TAD | Two complement add AC + MEM → AC | |
| 2 | izn0 | ME | M | ISZ | Increment MEM skip 0 | |
| 3 | izn0 | ME | M | DCA | AC → MEM, þen 0 → AC. | |
| 4 | izn0 | ME | M | JMS | JMP to Sub STORE RETURN IN FIRST WORD OF SUB! | |
| 5 | izn0 | ME | M | JMP | jmup | |
| ¤ | 6 | x | x | x | IOT | Input / Output inſtructions |
| 6 | 0 | 0 | ... | IOT | DEVICE: handled by processor 1 | |
| 6 | 0 | 1 | ... | IOT | DEVICE: paper tape reader | |
| 6 | 0 | 2 | ... | IOT | DEVICE: paper tape punch | |
| 6 | 0 | 3 | ... | IOT | DEVICE: console keyboard | |
| 6 | 0 | 4 | ... | IOT | DEVICE: console printer | 6 | d | d | ... | IOT | DEVICE: 04oct–77oct ergo: 59dec free devices. | 6 | d | d | 4 | (IOT) | (bit 9dec)AC to DEVICE,init I/O transfer, Clear ready2 | 6 | d | d | 2 | (IOT) | (bit 10dec)Clear AC2 | 6 | d | d | 1 | (IOT) | (bit 11dec)skip if ready2 |
| ¤ | 7 | x | x | x | OPR | ſee table 2: |
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | ||
| 1 | 1 | 1 | 0 | Clear AC {1} | Clear L {1} | ∁AC {2} | ∁L {2} | Rotate <L,AC> right {4} | Rotate <L,AC> left {4} | Byteswap, (PDP 8/e and hiȝr) {4} | INC <L,AC> {3} | ||
| 1 | 1 | 1 | 1 | Clear AC {2} | Skip if AC < 0 {1} | Skip if AC = 0 {1} | Skip if L ≠ 0 {1} | 0 | Front Panel ∨ AC (→ AC?) {3} | HLT {3} | 0 | ||
| 1 | 1 | 1 | 1 | Clear AC {2} | Skip if AC ≥ 0 {1} | Skip if AC ≠ 0 {1} | Skip if L = 0 {1} | 1 | Front Panel ∨ AC (→ AC?) {3} | HLT {3} | 0 | ||
| 1 | 1 | 1 | 1 | Clear AC {1} | MQ ∨ AC → AC {1} | SC → AC {1} | AC → MQ, 0 → AC {1} | code4 {3} | code4 {3} | code4 {3} | 1 |