Description
VCC Supply voltage VSS Circuit ground Port 0 Port 0 is an 8-bit open drain bidirectional I O port As an output port each pin can sink several inputs Port 0 pins that have 1’s written to them float and in that state can be used as high-impedance inputs Port 0 is also the multiplexed low-order address and data bus during accesses to external Program and Data Memory In this application it uses strong internal pullups when emitting 1’s and can source and sink several inputs Port 0 also receives the
Features
- of the MCS-51 Family as listed below Port Pin P3 0 P3 1 P3 2 P3 3 P3 4 P3 5 P3 6 P3 7 Alternate Function RXD (serial input port) TXD (serial output port) INT0 (external interrupt 0) INT1 (external interrupt 1) T0 (Timer 0 external input) T1 (Timer 1 external input) WR (external data memory write strobe) RD (external data memory read strobe)
PIN.
87L54 Datasheet
