Component: IO Expander (MCP23017) (Comms: System)

Author	Matrix TSL
Version	1.0
Category	Comms: System

IO Expander component

Provides 16 digital input/output pins arranged into two 8-bit ports using a I2C bus connection. Up to eight expanders can be connected to the same I2C peripheral by means of three address pins.

Component Pack

COMMSA

Detailed description

No detailed description exists yet for this component

Examples

No additional examples

Downloadable macro reference

	ReadPort
Reads a value to one of the ports with a mask. Configures the masked bits to be inputs before reading the input value.
- BYTE	Port
0=PortA, 1=PortB
- BYTE	Mask
Allows port bits to be modified without effecting other bits, 255 = write full port.
- BYTE	Return

	ConfigureInversion
Configures the pin inversion for the two ports. Disabled on all pins by default.
- BYTE	PortA
Port A inversion sent as an 8-bit value, 0 = Disabled, 1 = Enabled
- BYTE	PortB
Port B inversion sent as an 8-bit value, 0 = Disabled, 1 = Enabled
- VOID	Return

	ReadPortPin
Reads a single port pin from one of the ports. Configures the pins to be an input before reading the input value. Returns 0 or 1 corresponding to the value on the port pin.
- BYTE	Port
0=PortA, 1=PortB
- BYTE	Pin
Port pin to read. Range: 0-7
- BYTE	Return

	WritePortPin
Writes a single port pin on one of the ports. Configures the pins to be an output before writing the input value.
- BYTE	Port
0=PortA, 1=PortB
- BYTE	Pin
Port pin to read. Range: 0-7
- BYTE	Value
Value to output on the selected pin. Range: 0-1
- VOID	Return

	WritePort
Writes a value to one of the ports with a mask. Configures the masked bits to be outputs before writing the output value.
- BYTE	Port
0=PortA, 1=PortB
- BYTE	Mask
Allows port bits to be modified without effecting other bits, 255 = write full port.
- BYTE	Value
Value to write. Range 0-255
- VOID	Return

	ConfigurePullups
Configures the pullups for the two ports. Disabled on all pins by default.
- BYTE	PortA
Port A pull ups sent as an 8-bit value, 0 = Disabled, 1 = Enabled
- BYTE	PortB
Port B pull ups sent as an 8-bit value, 0 = Disabled, 1 = Enabled
- VOID	Return

	ReadRegister
Reads an 8-bit value from a register on the I/O expander device.
- BYTE	Address
Register address to write to. Range: 0-15
- BYTE	Return

	SetAddress
Allows the slave address to be overridden to allow multiple modules to be controlled using a single component.
- BYTE	Address
Range: 0-7
- VOID	Return

	WriteRegister
Writes an 8-bit value to a register on the I/O expander device.
- BYTE	Address
Register address to write to. Range: 0-15
- BYTE	Value
Value to write. Range: 0-255
- VOID	Return

	Initialise
- VOID	Return

Property reference

	Properties
	I²C Communications
	External Address
Selects the value of the three address pins for the MCP23S17.
	Channel
Channel selection
	Stop Delay
On older microcontroller devices there is a potential for the I2C hardware channel to lock up if there is not a 10ms delay between an I2C stop event and the next I2C start event. Most modern microcontrollers will not have a problem so this property can be disabled to speed up the I2C communications.
	Baud Select
Baud rate option selector
	Baud Rate
Baud rate to be used
	SDA
Pin used for SDA (data signal)
	SCL
Pin used for SCL (clock signal)
	Use Reset
	Simulation
	Label
	Scope Traces
Selects if the scope traces are automatically generated or not
	Console Data
Selects if the console data is automatically generated or not
	API