Editing Intel 8080 (section)

=====8-bit instructions=====
All 8-bit operations with two operands can only be performed on the 8-bit [[Accumulator (computing)|accumulator]] (the A register). The other operand can be either an immediate value, another 8-bit register, or a memory byte addressed by the 16-bit register pair HL. Increments and decrements can be performed on any 8 bit register or an HL-addressed memory byte. Direct copying is supported between any two 8-bit registers and between any 8-bit register and an HL-addressed memory byte. Due to the regular encoding of the {{code|MOV}} instruction (using a quarter of available opcode space), there are redundant codes to copy a register into itself ({{code|MOV B,B}}, for instance), which are of little use, except for delays. However, the systematic opcode for {{code|MOV M,M}} is instead used to encode the halt ([[HLT (x86 instruction)|{{code|HLT}}]]) instruction, halting execution until an external reset or interrupt occurs.