PCF8574 I2C Interface 8bit IO MCU Expansion Board I/O Expander I2C Bus Evaluation Development Module AVR STM8 C8051F For Arduino

Description

PCF8574 is an IO port expansion module that uses the I2C protocol. It has three address pins and can allocate up to 8 addresses simultaneously. The board includes 8-bit bidirectional IO ports (P0-P7), each of which can be separately assigned as an input or output without the need for data direction control signals. When powered on, all IO levels default to high level

Supply voltage: 3.3V/5V

Communication interface: I2C interface, 8-bit parallel port

Interface type: pin or socket

Interrupt output: connected to MCU interrupt pin, low level is valid

I2C Address Setting Instructions

The default I2C address of the module is 0x20

The I2C address can be set to 8 different addresses through A0-A2, as shown in the figure

All jumpers are set on the “-” side, meaning LOW is a low level

The “+” side is HIGH, which is a high level

The range of addresses from 0x20 to 0x27 is shown in the table below, which means that one development board can simultaneously connect 8 PCF8574 modules