Panasonic F77G, MN101C77C user manual bit Event Count, Count Timing TM7IO Input Timer

Chapter 7 16-bit Timer

7-4 16-bit Event Count

7-4-1 Operation

Event count operation has 2 types ; TM7IO input and synchronous TM7IO input can be selected as the count clock. Each type can select 1/1, 1/2, 1/4 or 1/6 as a count clock source.

„16-bit Event Count Operation (Timer 7)

Event count means that the binary counter (TM7BC) counts the input signal from external to the TM7IO pin. If the value of the binary counter reaches the setting value of the compare register (TM7OC), inter- rupts can be generated at the next count clock.

Table 7-4-1 Event Count Input Clock

Timer 7

TM7IO input

As an actual count clock, a

Event input

( P14 )

signal divided 1, 2, 4, or 16 is selected.

Synchronous

TM7IO input

„Count Timing of TM7IO Input (Timer 7)

When TM7IO input is selected, TM7IO input signal is directly input to the count clock of the timer 7. The binary counter counts up at the falling edge of the TM7IO input signal or at the falling edge of the TM7IO input signal that passed the divider.

TM7IO input

TM7EN flag

Compare

N

register 1

Binary	0000	0001	0002	N-1	N	0000 0001
counter

Interrupt request flag

Figure 7-4-1 Count Timing TM7IO Input (Timer 7)

If the binary counter is read out at operation, incorrect data at counting up may be read. To prevent this, use the event count by the synchronous TM7IO input as the following page.

16-bit Event Count VII - 15