| AC | accumulator |
| ALF | ALU function selector |
| ALU | arithmetic and logic unit |
| AL1 | first operand of ALU |
| AL2 | second operand of ALU |
| AR | address recognizer; portion of decoder |
| dba | destination bus address |
| E | extra or error output of ALU |
| FGI | input device flag |
| FGO | output device flag |
| INPR | input port |
| INT | micro address for interrupt |
| IR | instruction register |
| MAR | memory address register |
| MBR | memory buffer register |
| muPC | micro program counter |
| MUX | multiplexer |
| MS | multiplexer select input |
| M0 | multiplexer input, select with 0 |
| M1 | multiplexer input, select with 1 |
| OUTR | output port |
| PC | program counter |
| PG | pulse generator |
| RAM | random-access memory |
| ROM | read-only memory |
| sba | source bus address |