MC9S12E32CFU FREESCALE [Freescale Semiconductor, Inc], MC9S12E32CFU Datasheet - Page 531

• Manufacturer Part Number: MC9S12E32CFU
• Description: HCS12 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

This register is not in the on-chip memory map in expanded and special peripheral modes. Therefore, these
accesses will be echoed externally.
18.3.2.11 Reduced Drive Register (RDRIV)
Read: Anytime (provided this register is in the map)
Write: Anytime (provided this register is in the map)
This register is used to select reduced drive for the pins associated with the core ports. This gives reduced
power consumption and reduced RFI with a slight increase in transition time (depending on loading). This
feature would be used on ports which have a light loading. The reduced drive function is independent of
which function is being used on a particular port.
This register is not in the on-chip memory map in expanded and special peripheral modes. Therefore, these
accesses will be echoed externally.
Freescale Semiconductor
PUPKE
PUPEE
PUPBE
PUPAE
Field
7
4
1
0
Reset
W
R
Pull resistors Port K Enable
0 Port K pull resistors are disabled.
1 Enable pull resistors for port K input pins.
Pull resistors Port E Enable
0 Port E pull resistors on bits 7, 4:0 are disabled.
1 Enable pull resistors for port E input pins bits 7, 4:0.
Note: Pins 5 and 6 of port E have pull resistors which are only enabled during reset. This bit has no effect on
Pull resistors Port B Enable
0 Port B pull resistors are disabled.
1 Enable pull resistors for all port B input pins.
Pull resistors Port A Enable
0 Port A pull resistors are disabled.
1 Enable pull resistors for all port A input pins.
RDRK
These bits have no effect when the associated pin(s) are outputs. (The pull
resistors are inactive.)
0
7
these pins.
= Unimplemented or Reserved
0
0
6
Figure 18-15. Reduced Drive Register (RDRIV)
Table 18-9. PUCR Field Descriptions
MC9S12E128 Data Sheet, Rev. 1.07
0
0
5
NOTE
RDPE
0
4
Description
Chapter 18 Multiplexed External Bus Interface (MEBIV3)
3
0
0
2
0
0
RDPB
0
1
RDPA
0
0
531