MC9S12HZ256 Datasheet, PDF (146/692 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 4 Port Integration Module (PIM9HZ256V2)
4.3.5.5 Port S Pull Device Enable Register (PERS)
R
W
Reset
7
PERS7
0
6
5
4
3
2
0
0
PERS6
PERS5
PERS4
0
0
0
0
0
= Reserved or Unimplemented
Figure 4-34. Port S Pull Device Enable Register (PERS)
1
PERS1
0
0
PERS0
0
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated on configured input or
wired-or (open drain) output pins. If a pin is configured as push-pull output, the corresponding Pull Device
Enable Register bit has no effect.
Table 4-25. PERS Field Descriptions
Field
7:4
Pull Device Enable Port S
PERS[7:4] 0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
1:0
Pull Device Enable Port S
PERS[1:0] 0 Pull-up or pull-down device is disabled.
1 Pull-up or pull-down device is enabled.
Description
4.3.5.6 Port S Polarity Select Register (PPSS)
7
6
5
4
3
R
0
PPSS7
PPSS6
PPSS5
PPSS4
W
2
1
0
0
PPSS1
PPSS0
Reset
0
0
0
0
0
0
0
0
= Reserved or Unimplemented
Figure 4-35. Port S Polarity Select Register (PPSS)
Read: Anytime. Write: Anytime.
The Port S Polarity Select Register selects whether a pull-down or a pull-up device is connected to the pin.
The Port S 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.
MC9S12HZ256 Data Sheet, Rev. 2.04
146
Freescale Semiconductor