What are the XTAL 1 and XTAL 2 pins numbers for 8051?

Pin Diagram of 8051 microcontroller

1.) Pins 1 to 8: These pins are known as Port 1. This port doesn’t serve any other functions. It is an internally pulled-up, bi-directional I/O port

2.) Pin 9: It is a RESET pin, which is used to reset the microcontroller to its initial values.

3.) Pins 10 to 17: These pins are known as Port 3. This port serves some functions like interrupts, timer input, control signals, serial communication signals RxD and TxD, etc.

4.) Pins 18 & 19: The pins XTAL 1 and XTAL 2 are used for interfacing an external crystal to get the system clock.

5.) Pin 20: This pin provides the power supply to the circuit.

6.) Pins 21 to 28: These pins are known as Port 2. It serves as an I/O port. Higher-order address bus signals are also multiplexed using this port.

7.) Pin 29: This is the PSEN pin which stands for Program Store Enable. It is used to read a signal from the external program memory.

8.) Pin 30: This is the EA pin which stands for External Access input. It is used to enable/disable external memory interfacing.

9.) Pin 31: This is the ALE pin which stands for Address Latch Enable. It is used to demultiplex the address-data signal of the port.

10.) Pins 32 to 39: These pins are known as Port 0. It serves as an I/O port. Lower order address and data bus signals are multiplexed using this port.

11.) Pin 40: This pin is used to provide a power supply to the circuit.