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Programmer's Manual

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Overview

Each instruction (with no exception) takes one word in memory for the operational code (Op Cod). Some instructions take another word for additional data, which we call an "operand".

Arguments (as seen in assembly code) and operands do not necessarilly relate directly since, in most cases, arguments are embedded within the operational code.

Examples:

    mvi a, 0x03ff     ; The argument 0x03ff represents an operand. The 'a' is embedded in the Op Cod.
    mov a, b       ; Both arguments (a, b) are embedded within the Op Cod. No operand is employed.

The operational code is fetched in 3 clock periods (750 ns). Instructions with operand employ other 3 clock periods for operand fetching (for a total of 1.5 microseconds). Execution takes between 1 and 8 clock periods depending on the instruction. Average duration for an instruction (both fetch and exec cycles) is 6.5 clock cycles that is 1.6 microseconds.

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