Datasheet

Chapter 22 DP512 Port Integration Module (S12XDP512PIMV2)
MC9S12XDP512 Data Sheet, Rev. 2.21
Freescale Semiconductor 841
22.3.2.19 Port T Data Direction Register (DDRT)
Read: Anytime.
Write: Anytime.
This register configures each port T pin as either input or output.
The ECT forces the I/O state to be an output for each timer port associated with an enabled output compare.
In this case the data direction bits will not change.
The DDRT bits revert to controlling the I/O direction of a pin when the associated timer output compare
is disabled.
The timer input capture always monitors the state of the pin.
76543210
R
DDRT7 DDRT6 DDRT5 DDRT4 DDRT3 DDRT2 DDRT1 DDRT0
W
Reset 00000000
Figure 22-21. Port T Data Direction Register (DDRT)
Table 22-23. DDRT Field Descriptions
Field Description
7–0
DDRT[7:0]
Data Direction Port T
0 Associated pin is configured as input.
1 Associated pin is configured as output.
Note: Due to internal synchronization circuits, it can take up to 2 bus clock cycles until the correct value is read
on PTT or PTIT registers, when changing the DDRT register.