NXP Semiconductors MKW01Z128, Reference Manual

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System Considerations
MKW01xxRM Reference Manual, Rev. 3, 04/2016
4-14 Freescale Semiconductor, Inc.
— If ClkOut is used to drive the external clock source to the MCU, EXTAL (PTA18) is not
available as GPIO.
— PTA20 can be used as MCU reset.
• fourteen additional MCU GPIO are available for use in the SiP package. Four of them (PTB0,
PTB1, PTD6, PTD7) have 20mA drive capability and can drive LEDs directly.
NOTE
Unused GPIO pins should be disabled and if possible left unconnected.
NOTE
Four additional MCU GPIO are not pinned-out and cannot be used.
However, they must be initialized for low power operation.
— If a crystal is used with the MCU, PTA19/XTAL0 and PTA18/EXTAL0 pins cannot be used as
GPIO. These are available only using the internal clock reference.
— If ClkOut is used to drive the external clock source to the MCU, EXTAL0 is not available as
GPIO.
— PTA0, PTA3 and PTA20 are not commonly used as GPIOs because they are dedicated to the
MCU debug port (SWD).
4.5.1 MCU GPIO Characteristics
The internal MCU GPIO hardware consists of 5 ports with 32 signals per port for a total of 160 signals
(not all are available on the MKW01Z128). There are 8 signals from PTA, 5 from PTB, 9 from PTC, 5 from
PTD and 9 from PTE, many of which are dedicated to some function. This can be seen in
Figure 1-1 .
NOTE
To avoid extra current drain, all unused signals should be disabled. This
includes signals not pinned-out on the package.
• The GPIO ports share the pins with other modules and selection of either GPIO or a selection of
altenative modules signals are configured via the PORT control module. The PORT control
module provides up to 7 possible options for each external pin, and also provides optional
pull-up/pull-down devices when GPIO pin is input, and interrupt capability where available. See
section 7 of the MCU portion of this reference manual, Port Control.
• For information about how and when on-chip peripheral systems use these pins, refer to the
appropriate peripheral chapter of this document
4.5.2 Transceiver DIOX Characteristics
The transceiver status/GPIO consists of 6 signals total (DIO5-DIO0). DIO2 is bidirectional and all others
are output only. Immediately after reset, all the DIO are configured as outputs. Use of the DIO is controlled
by transceiver registers RegDioMapping1 and RegDioMapping2, see
Section 7.10, “IRQ and Pin
Mapping Registers” .