S912XEG384J3VA Datasheet, PDF (133/1324 Pages) Freescale Semiconductor, Inc – MC9S12XEP100 Reference Manual Covers MC9S12XE Family

Chapter 2 Port Integration Module (S12XEPIMV1)
Table 2-35. DDRM Register Field Descriptions (continued)
Field
4
DDRM
3
DDRM
2
DDRM
1
DDRM
0
DDRM
Description
Port M data direction—
This register controls the data direction of pin 4.
The enabled CAN2, routed CAN0, or routed CAN4 forces the I/O state to be an input. Depending on the configuration
of the enabled routed SPI0 this pin will be forced to be input or output.In those cases the data direction bits will not
change. The DDRM bits revert to controlling the I/O direction of a pin when the associated peripheral module is
disabled.
1 Associated pin is configured as output.
0 Associated pin is configured as input.
Port M data direction—
This register controls the data direction of pin 3.
The enabled CAN1 or routed CAN0 forces the I/O state to be an output. Depending on the configuration of the
enabled routed SPI0 this pin will be forced to be input or output. In those cases the data direction bits will not change.
The DDRM bits revert to controlling the I/O direction of a pin when the associated peripheral module is disabled.
1 Associated pin is configured as output.
0 Associated pin is configured as input.
Port M data direction—
This register controls the data direction of pin 2.
The enabled CAN1 or routed CAN0 forces the I/O state to be an input. Depending on the configuration of the enabled
routed SPI0 this pin will be forced to be input or output.In those cases the data direction bits will not change. The
DDRM bits revert to controlling the I/O direction of a pin when the associated peripheral module is disabled.
1 Associated pin is configured as output.
0 Associated pin is configured as input.
Port M data direction—
This register controls the data direction of pin 1.
The enabled CAN0 forces the I/O state to be an output. In those cases the data direction bits will not change. The
DDRM bits revert to controlling the I/O direction of a pin when the associated peripheral module is disabled.
1 Associated pin is configured as output.
0 Associated pin is configured as input.
Port M data direction—
This register controls the data direction of pin 0.
The enabled CAN0 forces the I/O state to be an input. In those cases the data direction bits will not change. The
DDRM bits revert to controlling the I/O direction of a pin when the associated peripheral module is disabled.
1 Associated pin is configured as output.
0 Associated pin is configured as input.
NOTE
Due to internal synchronization circuits, it can take up to 2 bus clock cycles
until the correct value is read on PTM or PTIM registers, when changing the
DDRM register.
MC9S12XE-Family Reference Manual Rev. 1.25
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