System Integration Unit (SIU)MPC5644A Microcontroller Reference Manual, Rev. 6Freescale Semiconductor 381Chapter 16System Integration Unit (SIU)16.1 OverviewThe System integration unit (SIU) controls this device’s reset configuration, pad configuration, externalinterrupt, general purpose I/O (GPIO), internal peripheral multiplexing, and the system reset operation.The reset configuration block contains the external pin boot configuration logic. The pad configurationblock controls the static electrical characteristics of I/O pins. The GPIO block provides uniform anddiscrete input/output control of the MCU I/O pins. The reset controller performs reset monitoring ofinternal and external reset sources, and drives the RSTOUT pin. The SIU is accessed by the core throughthe peripheral bus.16.2 Features• System configuration— MCU reset configuration via external pins— Pad configuration control• System reset monitoring and generation— Power-on reset support— Reset Status Register provides last reset source to software— Glitch detection on reset input— Software controlled reset assertion• External interrupt— 15 interrupt requests— 1 Non-Maskable/Critical Interrupt request (NMI)— Rising or falling edge event detection— Programmable digital filter for glitch rejection• GPIO— GPIO function on 163 I/O pins— Dedicated input and output registers for each GPIO pin• Internal multiplexing— Allows serial and parallel chaining of DSPIs— Allows flexible selection of eQADC trigger inputs— Allows selection of interrupt requests between external pins and DSPI— Allows selection of some eTPU inputs from external eTPU pins or deserialized output from theDSPI module— Allows selection of serialized data source for the DSPI
