The controller always starts executing instructions from the very beginning of the code memory. Advanced Features & Pin Configuration 14. What is the function of the EA pin? Answer: External Access.

Core electronics companies (like Bosch, Intel, or TI) often test basic architecture. Exams: Standard part of the ECE/EEE curriculum. 💾 8051 Microcontroller MCQ PDF Download Link

When tied to GND, the 8051 fetches code from external memory; when tied to Vcc, it uses internal ROM first.

Answer: Accumulator (Reg A).

TMOD (Timer Mode) configures the gate, counter/timer selection, and the mode (0-3). 10. What is SBUF used for? Answer: Serial data buffer.

MOV A, source is the standard instruction for internal data transfer. 12. What does the instruction DJNZ stand for? Answer: Decrement and Jump if Not Zero.

Answer: 128 bytes of RAM and 4KB of ROM.