8051 MICROCONTROLLER
ARCHITECTURE OF 8085
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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copy R1 to the accumulator
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copy the accumulator to R1
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copy the contents of memory whose address is in R1 to the accumulator
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copy the accumulator to the contents of memory whose address is in R1
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Detailed explanation-1: -In the instruction MOV A, R1; R1 stores the address from where the contents must be copied and stored in the accumulator. The sign is used to register indirect addressing in the instructions. Hence, Option (C) is the correct answer.
Detailed explanation-2: -MOV A, R0 Here the value inside R0 is considered as an address, which holds the data to be transferred to accumulator. Example: If R0 holds the value 20H, and we have a data 2F H stored at the address 20H, then the value 2FH will get transferred to accumulator after executing this instruction.
Detailed explanation-3: -The R0 and R1 are used for 8-bit addresses, and DPTR is used for 16-bit addresses, no other registers can be used for addressing purposes. Let us see some examples of this mode. In the instructions, the symbol is used for register indirect addressing.