The MCP23017-E/SP has several 8-bit configuration registers for selecting input, output, and polarity. By writing the I/O configuration bits (IODIRA/B), the system master can activate the I/Os as either inputs or outputs. Each input or output register stores the data for that input or output. The Polarity Inversion register can be used to invert the polarity of the Input Port register. The system master has access to all registers.
- 16-bit remote bidirectional I/O port
- High-speed I2C interface
- Three hardware address pins to allow up to eight devices on the bus
- Configurable interrupt output pins
- INTA and INTB can be configured to operate independently or together
- Configurable interrupt source
- Polarity Inversion register to configure the polarity of the input port data
- External Reset input
- Low standby current: 1µA max.
- 1 x MCP23017-E/SP