ETC EngineeringMCQs
Home › Microprocessors & Microcontrollers › Which 8051 port is open-drain in its basic I/O structure and generally requires external pull-up resistors when used as general-purpose I/O?
MCQ Practice Question
Microprocessors & Microcontrollers8051 I/O

Which 8051 port is open-drain in its basic I/O structure and generally requires external pull-up resistors when used as general-purpose I/O?

  • APort 0
  • BPort 1
  • CPort 2
  • DPort 3
Report an error
Correct Answer: A. Port 0
Explanation: Classic 8051 Port 0 uses open-drain outputs and needs external pull-ups for general-purpose I/O operation.
Reference: Standard microprocessors and microcontrollers: 8051 i/o
Continue practicing: Microprocessors & Microcontrollers MCQs or browse all MCQs.