MC9S12E128CFUE Datasheet, PDF (160/606 Pages) Freescale Semiconductor, Inc – MC9S12E128 Data Sheet

Chapter 3 Port Integration Module (PIM9E128V1)
PTIx
0
1
PTx
0
1
PAD
DDRx
0
1
Digital ^{data out}
Module ^{output enable}
module enable
Figure 3-49. Illustration of I/O Pin Functionality
Figure 3-50 shows the state of digital inputs and outputs when an analog module drives the port. When the
analog module is enabled all associated digital output ports are disabled and all associated digital input
ports read “1”.
Digital
Input
11
0
Module
Enable
Analog
Module
Analog
Output
Digital
Output
0
1
PAD
PIM Boundary
Figure 3-50. Digital Ports and Analog Module
3.4.4 Reduced Drive Register
If the port is used as an output the Reduced Drive Register allows the configuration of the drive strength.
3.4.5 Pull Device Enable Register
The Pull Device Enable Register turns on a pull-up or pull-down device. The pull device becomes active
only if the pin is used as an input or as a wired-or output.
MC9S12E128 Data Sheet, Rev. 1.07
160
Freescale Semiconductor