List of Mnemonics

⇦ list 30...3F   ⇧ table   list 50...5F ⇨

Opcode Mnemonic Description
40 INCI Increment register I (number 00)
41 DECI Decrement register I
42 INCA Increment register A (number 02)
43 DECA Decrement register A
44 ADM Add accumulator to (internal) Memory register (p)
45 SBM Subtract accumulator from register (p)
46 ANMA And operation in register (p) with Accumulator
47 ORMA Or operation in register (p) with Accumulator
48 INCK Increment register K (number 08)
49 DECK Decrement register K
4A INCM Increment register M (number 0A)
4B DECM Decrement register M
4C INA store Input from port A in accumulator
4D NOPW No operation (two cycles)
4E #b WAIT #b Wait for #b processor cycles
4F WAIT1 Wait for input port Xin to become 1


Language Conventions.

I/O ports
The SC61860 processor is connected to external devices and chips like the keyboard (input ports A and B, output ports A, B, F, and C) and main data memory. The port Xin belongs to the pin connector that permits to load and store programs via audio signals. Xin = 1 (0) means something like „high (low) frequency“.
CPU clock
One cycle takes about 5.2µs. This can be measured with a mechanical stopwatch, repeating a WAIT statement for about 655 360 times.