Signal Description
PXN20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor 3-21
3.4 Detailed Signal Description
This section provides detailed descriptions of the signal functions available for the device.
3.4.1 Port A Pins
3.4.1.1 PA0 to PA13 — GPI (PA[0:13]) / Analog Input (AN[0:13])
PA[0:13] are general-purpose input (GPI) pins. AN[0:13] are single-ended analog input pins.
3.4.1.2 PA14 — GPI (PA[14]) / Analog Input (AN[14]) / 32 kHz Crystal Input
(EXTAL32)
PA[14] is a general-purpose input (GPI) pin. AN[14] is a single-ended analog input pin. EXTAL32 is the
input pin for an external 32 kHz crystal oscillator.
3.4.1.3 PA15 — GPI (PA[15]) / Analog Input (AN[15]) / 32 kHz Crystal Output
(XTAL32)
PA[15] is a GPI pin. AN[15] is a single-ended analog input pin. XTAL32 is the output pin for an external
32 kHz crystal oscillator.
3.4.2 Port B Pins
3.4.2.1 PB0 — GPIO (PB[0]) / Analog Input (AN[16]) / Analog Input Channel for
External Mux (ANW)
PB[0] is a GPIO pin. AN[16] is a single-ended analog input pin. ANW is an input channel for the ADC
external multiplexer.
3.4.2.2 PB1 — GPIO (PB[1]) / Analog Input (AN[17]) / Analog Input Channel for
External Mux (ANX)
PB[1] is a GPIO pin. AN[17] is a single-ended analog input pin. ANX is an input channel for the ADC
external multiplexer.
3.4.2.3 PB2 — GPIO (PB[2]) / Analog Input (AN[18]) / Analog Input Channel for
External Mux (ANY)
PB[2] is a GPIO pin. AN[18] is a single-ended analog input pin. ANY is an input channel for the ADC
external multiplexer.