Panasonic F77G User Manual page 311

Count Timing of Timer Operation (Time Base Timer)
The counter counts up with the selected clock source as a count clock.
14 13 12 11 10
13
15
1/2 1/2
Figure 8-4-1
When the selected interrupt cycle has passed, the interrupt request flag of the time base
interrupt control register (TBICR) is set to "1".
An interrupt may be generated at switching of the clock source. Enable interrupt after switch-
ing the clock source.
Time base timer cannot stop the operation.
The initialization can be done by writing an arbitrary value to the time base timer clear control
register (TBCLR).
9 8 7 6 5 4
10 8
9 7
1/2 1/2 1/2 1/2
Count Timing of Timer Operation (Time Base Timer)
Chapter 8 Time Base Timer / 8-bit Free-running Timer
3 2 1 0
MUX
fosc
fx
VIII - 13
Time Base Timer