87L58 - Intel Corporation

87L58 LOW VOLTAGE CHMOS SINGLE-CHIP 8-BIT MICROCONTROLLERS

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 .

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 DESCRIPTIONS 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-impe.