描述 Description

The MCP23X08 device provides 8-bit, general purpose, parallel I/O expansion for I2C bus or SPI applications. The two devices differ in the number of hardware address pins and the serial interface:
? MCP23008 – I2C interface; three address pins
? MCP23S08 – SPI interface; two address pins The MCP23X08 consists of multiple 8-bit configuration registers for input, output and polarity selection. The system master can enable the I/Os as either inputs or outputs by writing the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register. All registers can be read by the system master.

特性 Features

8-bit port expander with interrupt output
3 address inputs for up to 8 devices on one bus
25mA sink/source capability per I/O
Supports 100kHz, 400kHz and 1.7MHz I2C?Compatible modes
Internal power-on-reset (POR)

簡(jiǎn)介

MCP23008屬于集成電路（IC）的I/O擴(kuò)展器。由制造生產(chǎn)的MCP23008I/O 擴(kuò)展器該系列器件可與微控制器、微處理器或類似器件結(jié)合使用，目的是增加可用于連接外設(shè)的信號(hào)連接數(shù)量。典型的工作概念涉及使用串行通信，只需主機(jī)設(shè)備上的幾根 I/O 線，即可讀/寫擴(kuò)展器設(shè)備上的許多輸入/輸出引腳的狀態(tài)。該技術(shù)的通信速度不佳，但連通性較高，最適合快速響應(yīng)不是很關(guān)鍵的應(yīng)用，例如許多人機(jī)界面應(yīng)用。