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It is hard to answer your question. We do not know which microprocessor you are trying to operate, or how.
Do you just have one in hand, and need to know how to program it? If so, obtain the data sheet for the device, along with the appropriate programmer package from the manufacturer.
This instruction copies the contents of the source register into the destination register; the contents of the source register are not altered. If one of the operands is a memory location, its location is specified by the contents of the HL registers.
Example: MOV B, C or MOV B, M
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