
Chapter 2 Port Integration Module (S12XEPIMV1)
MC9S12XE-Family Reference Manual , Rev. 1.07
128
Freescale Semiconductor
2.3.40
Port M Reduced Drive Register (RDRM)
2.3.41
Port M Pull Device Enable Register (PERM)
Address 0x0253
Access: User read/write
1
1
Read: Anytime.
Write: Anytime.
7
6
5
4
3
2
1
0
R
RDRM7
RDRM6
RDRM5
RDRM4
RDRM3
RDRM2
RDRM1
RDRM0
W
Reset
0
0
0
0
0
0
0
0
Figure 2-38. Port M Reduced Drive Register (RDRM)
Table 2-35. RDRM Register Field Descriptions
Field
Description
7-0
RDRM
Port M reduced drive
—Select reduced drive for outputs
This register configures the drive strength of Port M output pins 7 through 0 as either full or reduced. If a pin is used
as input this bit has no effect.
1 Reduced drive selected (1/6 of the full drive strength).
0 Full drive strength enabled.
Address 0x0254
Access: User read/write
1
1
Read: Anytime.
Write: Anytime.
7
6
5
4
3
2
1
0
R
PERM7
PERM6
PERM5
PERM4
PERM3
PERM2
PERM1
PERM0
W
Reset
0
0
0
0
0
0
0
0
Figure 2-39. Port M Pull Device Enable Register (PERM)
Table 2-36. PERM Register Field Descriptions
Field
Description
7-0
PERM
Port M pull device enable
—Enable pull-up devices on input pins
These bits configure whether a pull device is activated, if the associated pin is used as an input or wired-or output.
This bit has no effect if the pin is used as push-pull output. Out of reset no pull device is enabled.
1 Pull device enabled.
0 Pull device disabled.