PXD10RM Datasheet, PDF (1195/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

Chapter 37
System Integration Unit Lite (SIUL)
37.1 Introduction
This chapter describes the System Integration Unit Lite (SIUL), which is used for the management of the
pads and their configuration. It controls the multiplexing of the alternate functions used on all pads as well
as being responsible for the management of the external interrupts to the device.
37.2 Overview
The SIUL controls the MCU pad configuration, ports, general-purpose input and output (GPIO) signals
and external interrupts with trigger event configuration. Figure 37-1 is a block diagram of the SIUL and
its interfaces to other system components.
The module provides dedicated general-purpose pads that can be configured as either inputs or outputs.
When configured as an output, you can write to an internal register to control the state driven on the
associated output pad. When configured as an input, you can detect the state of the associated pad by
reading the value from an internal register. When configured as an input and output, the pad value can be
read back, which can be used a method of checking if the written value appeared on the pad.
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
37-1