Device Class

Encapsulates the MCP23S17 SPI I/O GPIO Expander.

Inheritance Hierarchy

SystemObject
IO.Devices.MCP23S17Device

Namespace: IO.Devices.MCP23S17
Assembly: libsimpleio (in libsimpleio.dll) Version: 2.2025.76.2

Syntax

public class Device

The Device type exposes the following members.

Constructors

	Name	Description
	Device	Constructor for a single MCP23S17 device.

Properties

	Name	Description
	Direction	Data Direction Property (16 bits). Bits 0 to 7 correspond to PORT A and bits 8 to 15 correspond to PORT B. For each bit, 0=input and 1=output.
	DirectionA	Port A Data Direction Property (8 bits). For each bit, 0=input and 1=output.
	DirectionB	Port B Data Direction Property (8 bits). For each bit, 0=input and 1=output.
	Polarity	Data Polarity Property (16 bits). Bits 0 to 7 correspond to PORT A and bits 8 to 15 correspond to PORT B. For each bit, 0=input and 1=output.
	PolarityA	Port A Data Polarity Property (8 bits). For each bit, 0=input and 1=output.
	PolarityB	Port B Data Polarity Property (8 bits). For each bit, 0=input and 1=output.
	Port	Port Data Property (16 bites). Bits 0 to 7 correspond to PORT A and bits 8 to 15 correspond to PORT B.
	PortA	Port A Data Property (8 bits).
	PortB	Port B Data Property (8 bits).
	Pullups	Input Pullup Property (16 bits). Bits 0 to 7 correspond to PORT A and bits 8 to 15 correspond to PORT B. For each bit, 0=high impedance and 1=100k pullup.
	PullupsA	Port A Input Pullup Property (16 bits). For each bit, 0=high impedance and 1=100k pullup.
	PullupsB	Port B Input Pullup Property (16 bits). For each bit, 0=high impedance and 1=100k pullup.

Methods

	Name	Description
	GPIO_Create	Create an MCP23S17 GPIO pin object.

Fields

	Name	Description
	MaxChannel	Maximum I/O channel number.
	MinChannel	Minimum I/O channel number.
	SPI_Frequency	SPI maximum clock frequency in Hz.
	SPI_Mode	SPI transfer mode.
	SPI_WordSize	SPI transaction word size.