System Integration Unit (SIU)MPC5566 Microcontroller Reference Manual, Rev. 26-4 Freescale Semiconductor6.2 External Signal DescriptionTable 6-3 lists the external pins used by the SIU.6.2.1 Detailed Signal Descriptions6.2.1.1 Reset Input (RESET)RESET is an active-low input signal asserted by an external device during a power-on reset (POR) orexternal reset. If RESET asserts for ten clock cycles only, the internal reset signal asserts. Asserting theRESET signal while the device is processing a reset restarts the reset process at the beginning.RESET has a glitch detector logic that senses electrical fluctuations on the VDDEH input pins that dropbelow the switch point value for more than two clock cycles. The switch point value is between themaximum VIL and minimum VIH specifications for the VDDEH input pins.Table 6-3. SIU Signal PropertiesName Function I/OTypePadTypePullupPulldown 11 Internal weak pullup/down. The reset weak pullup/down state for the primary signal function is given. For example, the resetweak pullup/down state of the BOOTCFG[0:1]_GPIO[211:212] signal is weak pulldown enabled.ResetsRESET Reset input Input — UpRSTOUT Reset output Output Slow —System ConfigurationGPIO[0:210] General-purpose I/O I/O Slow Up/downBOOTCFG[0:1]_GPIO[211:212]Boot configuration inputGeneral-purpose I/OInputI/OSlow DownUp/downWKPCFG_GPIO[213]Weak-pull configurationGeneral-purpose I/OInputI/OSlow UpUp/downExternal InterruptIRQ[0:15] 22 The GPIO and IRQ signals are multiplexed with other functions on the device.External interrupt request input Input Slow — 33 The weak pullup/down state at reset for the IRQ signals depends on the muxed signals that share the pin. The weakpullup/down state for these pins is as follows:IRQ[0, 1, 4, 5, 6, 7, 12:14]UpIRQ[2, 3, 15] DownIRQ[8:11] WKPCFG
