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Chapter 1 Device Overview MC9S12XE-Family
MC9S12XE-Family Reference Manual Rev. 1.07
Freescale Semiconductor
57
1.2.3.37
PJ3 / KWJ3 — PORT J I/O Pin 3
PJ2 is a general-purpose input or output pins. It can be configured as a keypad wakeup input.
1.2.3.38
PJ2 / KWJ2 / CS1 — PORT J I/O Pin 2
PJ2 is a general-purpose input or output pins. It can be configured as a keypad wakeup input. It can also
be configured as chip-select output.
1.2.3.39
PJ1 / KWJ1 / TXD2 — PORT J I/O Pin 1
PJ1 is a general-purpose input or output pin. It can be configured as a keypad wakeup input. It can be
configured as the transmit pin TXD of the serial communication interface 2 (SCI2).
1.2.3.40
PJ0 / KWJ0 / RXD2 / CS3 — PORT J I/O Pin 0
PJ0 is a general-purpose input or output pin. It can be configured as a keypad wakeup input. It can be
configuredasthereceivepinRXDoftheserialcommunicationinterface2(SCI2).Itcanalsobeconfigured
as chip-select output 3.
1.2.3.41
PK7 / EWAIT / ROMCTL — Port K I/O Pin 7
PK7 is a general-purpose input or output pin. During MCU emulation modes and normal expanded modes
of operation, this pin is used to enable the Flash EEPROM memory in the memory map (ROMCTL). At
the rising edge of RESET, the state of this pin is latched to the ROMON bit. The EWAIT input signal
maintains the external bus access until the external device is ready to capture data (write) or provide data
(read).
The input voltage threshold for PK7 can be configured to reduced levels, to allow data from an external
3.3-V peripheral to be read by the MCU operating at 5.0 V.
1.2.3.42
PK[6:4] / ADDR[22:20] / ACC[2:0] — Port K I/O Pin [6:4]
PK[6:4] are general-purpose input or output pins. During MCU expanded modes of operation, the
ACC[2:0] signals are used to indicate the access source of the bus cycle. This pins also provide the
expanded addresses ADDR[22:20] for the external bus. In Emulation modes ACC[2:0] is available and is
time multiplexed with the high addresses
1.2.3.43
PK[3:0] / ADDR[19:16] / IQSTAT[3:0] — Port K I/O Pins [3:0]
PK3-PK0 are general-purpose input or output pins. In MCU expanded modes of operation, these pins
provide the expanded address ADDR[19:16] for the external bus and carry instruction pipe information.
1.2.3.44
PL7 / TXD7 — Port L I/O Pin 7
PL7 is a general-purpose input or output pin. It can be configured as the transmit pin TXD of serial
communication interface 7 (SCI7).