Question
Download Solution PDFHow many dual-purpose ports are there in the 8051 microcontroller?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFPorts in 8051:
- There are 4 ports in 8051 IC (Port 0, Port 1, Port 2 and Port 3); 32 pins function as I/O port lines and 24 of these lines are dual-purpose (P0, P1, P3).
- Each can operate as I/O, or as a control line or part of the address or data bus.
- Eight lines in each port can be used in interfacing to parallel devices like printers, DAC, etc., or each line the port can be used in interfacing to single bit devices like LED’s, switches, transistors, solenoid, motors, and loudspeakers.
Important:
In an 8051 microcontroller,
- Internal RAM (data memory) - 128 bytes
- Internal memory (code memory) - 4 kB (ROM)
- Timer/counter - 2
- No. of interrupt - 5
- I/O pins - 32
- Serial port - 1
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