MC9S12E256 Datasheet, PDF (153/602 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

3.3.6.5
Chapter 3 Port Integration Module (PIM9E256V1)
Port T Pull Device Enable Register (PERT)
R
W
Reset
7
PERT7
0
6
PERT6
5
PERT5
4
PERT4
3
PERT3
2
PERT2
0
0
0
0
0
Figure 3-40. Port T Pull Device Enable Register (PERT)
1
PERT1
0
0
PERT0
0
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input pins. If
a pin is configured as output, the corresponding Pull Device Enable Register bit has no effect.
Table 3-29. PERT Field Descriptions
Field
7:0
Pull Device Enable Port T
PERT[7:0] 0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
Description
3.3.6.6 Port T Polarity Select Register (PPST)
R
W
Reset
7
PPST7
0
6
PPST6
5
PPST5
4
PPST4
3
PPST3
2
PPST2
0
0
0
0
0
Figure 3-41. Port T Polarity Select Register (PPST)
1
PPST1
0
0
PPST0
0
Read: Anytime. Write: Anytime.
The Port T Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port T Polarity Select Register is effective only when the corresponding Data Direction Register bit
is set to 0 (input) and the corresponding Pull Device Enable Register bit is set to 1.
Table 3-30. PPST Field Descriptions
Field
Description
7:0
Pull Select Port T
PPST[7:0] 0 A pull-up device is connected to the associated port T pin.
1 A pull-down device is connected to the associated port T pin.
MC9S12E256 Data Sheet, Rev. 1.08
Freescale Semiconductor
153