As with abounding added 8-bit processors, all instructions were encoded in a individual byte (including register-numbers, but excluding actual data), for simplicity. Some of them were followed by one or two bytes of data, which could be an actual operand, a anamnesis address, or a anchorage number. Like beyond processors, it had automated CALL and RET instructions for multi-level action calls and allotment (which could even be conditionally executed, like jumps) and instructions to save and restore any 16-bit register-pair on the apparatus stack. There were aswell eight one-byte alarm instructions (RST) for subroutines amid at the anchored addresses 00h, 08h, 10h,...,38h. These were advised to be supplied by alien accouterments in adjustment to adjure a agnate interrupt-service routine, but were aswell generally active as fast arrangement calls. The a lot of adult command was XTHL, which was acclimated for exchanging the annals brace HL with the amount stored at the abode adumbrated by the assemblage pointer.
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