NEC 78K0S/KB1+ User Manual page 91

Figure 6-5. Format of 16-bit Timer Mode Control Register 00 (TMC00)
Address: FF60H After reset: 00H
Symbol 7 6 5
TMC00 0 0 0
TMC003 TMC002 TMC001
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
OVF00
0 Overflow not detected
1 Overflow detected
Cautions 1. The timer operation must be stopped before writing to bits other than the OVF00 flag.
2. If the timer is stopped, timer counts and timer interrupts do not occur, even if a signal is
input to the TI000/TI010 pins.
3. Except when the valid edge of the TI000 pin is selected as the count clock, stop the timer
operation before setting STOP mode or system clock stop mode; otherwise the timer may
malfunction when the system clock starts.
4. Set the valid edge of the TI000 pin with bits 4 and 5 of prescaler mode register 00 (PRM00)
after stopping the timer operation.
5. If the clear & start mode entered on a match between TM00 and CR000, clear & start mode at
the valid edge of the TI000 pin, or free-running mode is selected, when the set value of CR000
is FFFFH and the TM00 value changes from FFFFH to 0000H, the OVF00 flag is set to 1.
6. Even if the OVF00 flag is cleared before the next count clock is counted (before TM00
becomes 0001H) after the occurrence of a TM00 overflow, the OVF00 flag is re-set newly and
clear is disabled.
7. The capture operation is performed at the fall of the count clock. An interrupt request input
(INTTM0n0), however, occurs at the rise of the next count clock.
Remark TM00: 16-bit timer counter 00
CR000: 16-bit timer capture/compare register 000
CR010: 16-bit timer capture/compare register 010
CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
R/W
4 3 2 1 <0>
0 TMC003 TMC002 TMC001 OVF00
Operating mode and clear
mode selection
Operation stop
(TM00 cleared to 0)
Free-running mode
Clear & start occurs on valid
edge of TI000 pin
Clear & start occurs on match
between TM00 and CR000
Overflow detection of 16-bit timer counter 00 (TM00)
User's Manual U17446EJ3V1UD
TO00 inversion timing selection
No change
Match between TM00 and
CR000 or match between
TM00 and CR010
Match between TM00 and
CR000, match between TM00
and CR010 or TI000 pin valid
edge
−
Match between TM00 and
CR000 or match between
TM00 and CR010
Match between TM00 and
CR000, match between TM00
and CR010 or TI000 pin valid
edge
Interrupt request generation
Not generated
<When operating as compare
register>
Generated on match between
TM00 and CR000, or match
between TM00 and CR010
<When operating as capture
register>
Generated on TI000 pin and
TI010 pin valid edge
91