mc9s12e256 Freescale Semiconductor, Inc, mc9s12e256 Datasheet - Page 133

• Manufacturer Part Number: mc9s12e256
• Description: Hcs12 Microcontrollers 16-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

3.3.1.6
Read: Anytime. Write: Anytime.
The Port AD Polarity Select 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 (PERADx = 1). The Port AD Polarity
Select Register is effective only when the corresponding Data Direction Register bit is set to 0 (input).
In pull-down mode (PPSADx = 1), a rising edge on a port AD pin sets the corresponding PIFADx bit. In
pull-up mode (PPSADx = 0), a falling edge on a port AD pin sets the corresponding PIFADx bit.
Freescale Semiconductor
PPSAD[15:0]
Reset
Reset
Field
15:0
W
W
R
R
PPSAD15
PPSAD7
Polarity Select Port AD
0 A pull-up device is connected to the associated port AD pin, and detects falling edge for interrupt generation.
1 A pull-down device is connected to the associated port AD pin, and detects rising edge for interrupt
Port AD Polarity Select Register (PPSAD)
0
0
7
7
generation.
PPSAD14
PPSAD6
0
0
6
6
Figure 3-7. Port AD Polarity Select Register (PPSAD)
PPSAD13
Table 3-6. PPSAD Field Descriptions
PPSAD5
MC9S12E256 Data Sheet, Rev. 1.08
0
0
5
5
PPSAD12
PPSAD4
0
0
4
4
Description
PPSAD11
PPSAD3
3
0
3
0
Chapter 3 Port Integration Module (PIM9E256V1)
PPSAD10
PPSAD2
0
0
2
2
PPSAD9
PPSAD1
0
0
1
1
PPSAD8
PPSAD0
0
0
0
0
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