MC9S12KG128 Datasheet, PDF (165/600 Pages) Freescale Semiconductor, Inc – Microcontrollers

4.3.5.5
Chapter 4 Port Integration Module (PIM9KG128V1)
Port H Pull Device Enable Register (PERH)
Module Base + 0x0024
7
R
PERH7
W
6
PERH6
5
PERH5
4
PERH4
3
PERH3
2
PERH2
1
PERH1
0
PERH0
Reset
0
0
0
0
0
0
0
0
Figure 4-35. Port H Pull Device Enable Register (PERH)
Read: Anytime. Write: Anytime.
This register configures whether a pull-up or a pull-down device is activated, if the port is used as input.
This bit has no effect if the port is used as output. Out of reset no pull device is enabled.
Table 4-32. PERH Field Descriptions
Field
Description
7–0
Pull Device Enable Port H
PERH[7:0] 0 Pull-up or pull-down device is disabled.
1 Either a pull-up or pull-down device is enabled.
4.3.5.6 Port H Polarity Select Register (PPSH)
Module Base + 0x0025
7
R
PPSH7
W
6
PPSH6
5
PPSH5
4
PPSH4
3
PPSH3
2
PPSH2
Reset
0
0
0
0
0
0
Figure 4-36. Port H Polarity Select Register (PPSH)
Read: Anytime. Write: Anytime.
1
PPSH1
0
0
PPSH0
0
This register serves a dual purpose by selecting the polarity of the active interrupt edge as well as selecting
a pull-up or pull-down device if enabled.
Table 4-33. PPSH Field Descriptions
Field
Description
7–0
PPSH[7:0]
Polarity Select Port H
0 Falling edge on the associated port H pin sets the associated flag bit in the PIFH register. A pull-up device is
connected to the associated port H pin, if enabled by the associated bit in register PERH and if the port is used
as input.
1 Rising edge on the associated port H pin sets the associated flag bit in the PIFH register. A pull-down device
is connected to the associated port H pin, if enabled by the associated bit in register PERH and if the port is
used as input.
MC9S12KG128 Data Sheet, Rev. 1.15
Freescale Semiconductor
165