29.1 Overview

The I/O Pin Controller (PORT) controls the I/O pins of the device. The I/O pins are organized in a series of groups, collectively referred to as a PORT group. Each PORT group can have up to 32 pins that can be configured and controlled individually or as a group. The number of PORT groups on a device may depend on the package or number of pins. Each pin may either be used for general purpose I/O under direct application control or be assigned to an embedded device peripheral. When used for general purpose I/O, each pin can be configured as input or output, with a highly configurable driver and pull settings.

All I/O pins have true read-modify-write functionality when used for general purpose I/O. The direction or the output value of one or more pins may be changed (set, Reset or toggled) explicitly without unintentionally changing the state of any other pins in the same port group by a single, atomic 8-bit, 16-bit, or 32-bit write.

The PORT is connected to the high-speed bus matrix through an AHB/APB bridge.