System Integration Unit (SIU)MPC5566 Microcontroller Reference Manual, Rev. 2Freescale Semiconductor 6-36.1.2 OverviewThe system integration unit (SIU) is accessed by the e200z6 core through the system bus crossbar switch(XBAR) and the peripheral bridge A (PBRIDGE_A). Table 6-1 lists the features the SIU configures::6.1.3 Modes of OperationThe MPC5500 family of devices has several operating modes for configuring and testing the chip:Table 6-1. SIU FeaturesFeature DescriptionMCU reset operations Controls the external pin boot logicSystem reset operations Monitors internal and external reset sources, and drives the RSTOUT signal• Power-on reset support• Reset status register providing last reset source to software• Glitch detection on reset input• Software controlled reset assertionPad configuration registers Enables the configuration and initialization of the I/O pin electrical characteristics usingsoftware to select the following:• Active function from the set of multiplexed functions• Pullup and pulldown characteristics of the pin• Slew rate for slow and medium pads• Open drain mode for output pins• Hysteresis for input pins• Drive strength of bus signals for fast padsExternal interrupt operations • 16 interrupt requests• Rising- or falling-edge event detection• Programmable digital filter for glitch rejectionGeneral-purpose I/O (GPIO) Provides uniform and discrete I/O control of 178 MCU general-purpose I/O pins, whereeach GPIO signal has an input register and an output register.Internal peripheral multiplexing Provides flexibility to customize signal/pin assignments for application development thatallows:• Serial and parallel chaining of DSPIs• Flexible selection of eQADC trigger inputs• Assignment of interrupt requests (IRQs) between external pins and DSPITable 6-2. SIU Operating ModesOperating Mode DescriptionNormal In normal mode, the SIU provides the register interface and logic that controls the device andsystem configuration, the reset controller, and GPIO. The SIU continues operation with nochanges in stop mode.Debug SIU operation in debug mode is identical to operation in normal mode.
