HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 438

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

Bit 7—Overflow Flag (OVF): This status flag indicates that the timer counter has overflowed
from H'FF to H'00.
Bit 7
OVF
0
1
Bit 6—Timer Mode Select
interval timer. If used as an interval timer, the WDT generates an interval timer interrupt request
when TCNT overflows. If used as a watchdog timer, the WDT generates a reset signal when
TCNT overflows.
Bit 6
WT/IT
0
1
Bit 5—Timer Enable (TME): Selects whether TCNT runs or is halted.
When WT/IT = 1, clear the SYSCR software standby bit (SSBY) to 0, then set the TME to 1.
When SSBY is set to 1, clear TME to 0.
Bit 5
TME
0
1
Bits 4 and 3—Reserved: Read-only bits, always read as 1.
Description
[Clearing condition]
Cleared by reading OVF when OVF = 1, then writing 0 in OVF
[Setting condition]
Set when TCNT changes from H'FF to H'00
Description
Interval timer: requests interval timer interrupts
Watchdog timer: generates a reset signal
Description
TCNT is initialized to H'00 and halted
TCNT is counting and CPU interrupt requests are enabled
(WT/IT): Selects whether to use the WDT as a watchdog timer or
426
(Initial value)
(Initial value)
(Initial value)