Q.What is the function of Register A?

Register A is the accumulator of the 8051 — the main working register through which most arithmetic and logic operations are carried out. It holds one operand before, and the result after, such operations. …

[!TLDR]

Register A is the 8051's accumulator — the central 8-bit register for arithmetic, logic and data-transfer operations.

The accumulator, register A, is the most frequently used register in the 8051. It is an 8-bit register that supplies one operand to, and receives the result of, almost every arithmetic operation (ADD, SUBB, MUL, DIV) and logical operation (ANL, ORL, and so on). Data moving to or from external memory (MOVX) and code memory (MOVC) also passes through A. Because so many i …