Datasheet
Bus Control and Input/Output (I/O)
MC68HC812A4 Data Sheet, Rev. 7
72 Freescale Semiconductor
6.3.13 Reduced Drive Register
Read: Anytime, if register is in the map
Write: Anytime, in normal modes; never in special modes
This register is not in the map in peripheral mode.
These bits select reduced drive for the associated port pins. This gives reduced power consumption and
reduced RFI with a slight increase in transition time (depending on loading). The reduced drive function
is independent of which function is being used on a particular port.
RDPJ — Reduced Drive of Port J Bit
1 = Reduced drive for all port J output pins
0 = Full drive for all port J output pins
RDPH — Reduced Drive of Port H Bit
1 = Reduced drive for all port H output pins
0 = Full drive for all port H output pins
RDPG — Reduced Drive of Port G Bit
1 = Reduced drive for all port G output pins
0 = Full drive for all port G output pins
RDPF — Reduced Drive of Port F Bit
1 = Reduced drive for all port F output pins
0 = Full drive for all port F output pins
RDPE — Reduced Drive of Port E Bit
1 = Reduced drive for all port E output pins
0 = Full drive for all port E output pins
RDPD — Reduced Drive of Port D Bit
1 = Reduced drive for all port D output pins
0 = Full drive for all port D output pins
RDPC — Reduced Drive of Port C Bit
1 = Reduced drive for all port C output pins
0 = Full drive for all port C output pins
RDPAB — Reduced Drive of Port A and Port B Bit
1 = Reduced drive for all port A and port B output pins
0 = Full drive for all port A and port B output pins
Address: $000D
Bit 7654321Bit 0
Read:
RDPJ RDPH RDPG RDPF RDPE PRPD RDPC RDPAB
Write:
Reset:00000000
Figure 6-13. Reduced Drive Register (RDRIV)
