Port Integration Module (S12XSPIMV1)
S12XS Family Reference Manual, Rev. 1.13
122
Freescale Semiconductor
NOTE
Due to internal synchronization circuits, it can take up to 2 bus clock cycles
until the correct value is read on port data or port input registers, when
changing the data direction register.
Figure 2-73. Illustration of I/O pin functionality
2.4.2.4
Reduced drive register (RDRx)
If the pin is used as an output this register allows the configuration of the drive strength independent of the
use with a peripheral module.
2.4.2.5
Pull device enable register (PERx)
This register turns on a pull-up or pull-down device on the related pins determined by the associated
polarity select register (
The pull device becomes active only if the pin is used as an input or as a wired-or output. Some peripheral
modules only allow certain configurations of pull devices to become active. Refer to the respective bit
descriptions.
2.4.2.6
Polarity select register (PPSx)
This register selects either a pull-up or pull-down device if enabled.
It only becomes active if the pin is used as an input. A pull-up device can be activated if the pin is used as
a wired-or output.
PT
DDR
output enable
module enable
1
0
1
1
0
0
PIN
PTI
data out
Module
Summary of Contents for MC9S12XS128
Page 4: ...S12XS Family Reference Manual Rev 1 13 4 Freescale Semiconductor ...
Page 168: ...Interrupt S12XINTV2 S12XS Family Reference Manual Rev 1 13 168 Freescale Semiconductor ...
Page 736: ...Ordering Information S12XS Family Reference Manual Rev 1 13 736 Freescale Semiconductor ...
Page 737: ......