August 2014
Beginner
504 pages
11h 2m
English
Content preview from Mastering the Raspberry Pi
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
Start your free trial
CHAPTER 23
MCP23017 GPIO Extender
Microchip’s MCP23017 provides 16 additional GPIO pins that can be purchased for as little as $1.99. The chip communicates using the I2C bus. (The companion MCP23S17 is available for SPI bus.) The I2C bus allows the chip to be remote from the Raspberry Pi, requiring only a four-wire ribbon cable (power, ground, and a pair of I2C bus lines). This chapter explores the features and limits of this peripheral.
DC Characteristics
When shopping for chips or interface PCBs based on a particular chip, the first thing I look at is the operating supply voltage. 5 V parts are inconvenient for the Pi because of its 3.3 V GPIO ...