MC68HC05B4 Datasheet, PDF (257/298 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit

H.4.4 Mask option register
Preliminary ^{Mask option register (MOR)(1)}
Address bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
State
on reset
$7FDE
RTIM RWAT WWAT PBPD PCPD Not affected
(1) Because this register is implemented in EPROM, reset has no effect on the individual bits.
RTIM
This bit can modify the time t_PORL, where the RESET pin is kept low after a power-on reset.
1 (set) – t_PORL = 16 cycles.
0 (clear) – t_PORL = 4064 cycles.
RWAT
This bit can modify the status of the watchdog counter after reset. Usually, the watchdog system
Preliminary ^{is disabled after power-on or external reset but when this bit is set, it will be active immediately}
after the following resets (except in bootstrap mode).
WWAT
This bit can modify the status of the watchdog counter in WAIT mode. Normally, the watchdog
system is disabled in WAIT mode but when this bit is set, the watchdog will be active in WAIT mode.
PBPD
This bit, when programmed, connects a resistive pull-down on all 8 pins of port B. This pull-down,
R_PD, is active on a given pin only while it is an input.
PCPD
This bit, when programmed, connects a resistive pull-down on all 8 pins of port C. This pull-down,
Preliminary ^{RPD, is active on a given pin only while it is an input.}
14
MC68HC05B6
Rev. 4
MC68HC705B32
TPG
MOTOROLA
H-11