1.8.13 Parallel Input/Output (PIO) Controller

The Parallel Input/Output Controller (PIO) manages up to 32 fully programmable input/output lines. Each I/O line may be dedicated as a general-purpose I/O or be assigned to a function of an embedded peripheral. This ensures effective optimization of the pins of the product.

Using The Library

The PIO peripheral library provides two kinds of functions which can be used to control PIO Pins:

  • Pin Functions.

  • Port Functions.

Pin functions take a particular pin as input and operates only on that pin without affecting any other pins. Whereas port functions can operate on multiple pins of the same port together.

The PIO peripheral library can generate a callback on a pin interrupt if the pin interrupt is enabled in the MHC.

Library Interface

peripheral library provides the following interfaces:

Functions

Name Description
PIO_Initialize Initialize the PIO library
PIO_PortRead Read all the I/O lines of the selected port port
PIO_PortWrite Write the value on the masked I/O lines of the selected port
PIO_PortLatchRead Read the latched value on all the I/O lines of the selected port
PIO_PortSet Set the selected IO pins of a port
PIO_PortClear Clear the selected IO pins of a port
PIO_PortToggle Toggles the selected IO pins of a port
PIO_PortInputEnable Enables selected IO pins of a port as input
PIO_PortOutputEnable Enables selected IO pins of a port as output(s)
PIO_PortInterruptEnable Enables IO interrupt on selected IO pins of a port
PIO_PortInterruptDisable Disables IO interrupt on selected IO pins of a port
PIO_PinWrite Writes the selected pin
PIO_PinRead Read the selected pin value
PIO_PinLatchRead Read the value driven on the selected pin
PIO_PinToggle Toggles the selected pin
PIO_PinSet Sets the selected pin
PIO_PinClear Clears the selected pin
PIO_PinInputEnable Enables selected IO pin as input
PIO_PinOutputEnable Enables selected IO pin as output
PIO_PinInterruptEnable Enables IO interrupt on selected IO pin
PIO_PinInterruptDisable Disables IO interrupt on selected IO pin
PIO_PinInterruptCallbackRegister Allows application to register callback for every pin

Data types and constants

Name Type Description
PIO_PORT Enum Identifies the available PIO Ports
PIO_PIN Enum Identifies the available PIO port pins
PIO_PIN_CALLBACK Typedef Pointer to a PIO Pin-Event handler function