
Rev. 2.0, 11/00, page 395 of 1037
Bit 7: Overflow Flag (OVF)
A status flag that indicates that WTCNT has overflowed from H'FF to H'00.
Bit 7
OVF
Description
0
[Clearing conditions]
(Initial value)
(1) Write 0 in the TME bit
(2) Read WTCSR when OVF = 1, then write 0 in OVF
1
[Setting condition]
When WTCNT overflows (changes from H'FF to H'00)
When internal reset request generation is selected in watchdog timer mode, OVF is
cleared automatically by the internal reset
Bit 6: Timer Mode Select (WT/
,7
,7)
Selects whether the WDT is used as a watchdog timer or interval timer. If used as an interval
timer, the WDT generates an interval timer interrupt request (WOVI) when TCNT overflows. If
used as a watchdog timer, the WDT generates a reset or NMI interrupt when TCNT overflows.
Bit 6
WT/
,7
,7
Description
0
Interval timer mode: Sends the CPU an interval timer interrupt request (WOVI) when
WTCNT overflows
(Initial value)
1
Watchdog timer mode: Sends the CPU a reset or NMI interrupt request when
WTCNT overflows
Bit 5: Timer Enable (TME)
Selects whether WTCNT runs or is halted.
Bit 5
TME
Description
0
WTCNT is initialized to H'00 and halted
(Initial value)
1
WTCNT counts
Bit 4: Reset Select (RSTS)
Reserved. This bit should not be set to 1.
Содержание Hitachi H8S/2191
Страница 123: ...Rev 2 0 11 00 page 96 of 1037...
Страница 149: ...Rev 2 0 11 00 page 122 of 1037...
Страница 197: ...Rev 2 0 11 00 page 170 of 1037...
Страница 247: ...Rev 2 0 11 00 page 220 of 1037...
Страница 249: ...Rev 2 0 11 00 page 222 of 1037...
Страница 347: ...Rev 2 0 11 00 page 320 of 1037...
Страница 357: ...Rev 2 0 11 00 page 330 of 1037...
Страница 417: ...Rev 2 0 11 00 page 390 of 1037...
Страница 431: ...Rev 2 0 11 00 page 404 of 1037...
Страница 439: ...Rev 2 0 11 00 page 412 of 1037...
Страница 457: ...Rev 2 0 11 00 page 430 of 1037...
Страница 525: ...Rev 2 0 11 00 page 498 of 1037...
Страница 543: ...Rev 2 0 11 00 page 516 of 1037...
Страница 639: ...Rev 2 0 11 00 page 612 of 1037 28 1 2 Block Diagram Figure 28 1 shows a block diagram of the servo circuits...
Страница 845: ...Rev 2 0 11 00 page 818 of 1037...