NEC PD78214 - Manual (Page 147)

118
µ
PD78214 Sub-Series
Fig. 7-10 TM0 Cleared After a Coincidence Is Detected
Remark CLR01 = 1
(2) Capture operation
The 16-bit timer/counter performs a capture operation to load the count value of the timer into the capture
register in synchronism with an external trigger.
As an external trigger, a valid edge detected on the external interrupt request (INTP3) input pin is used (capture
trigger). In synchronism with a capture trigger, the count value of 16-bit timer 0 (TM0) in count operation is
loaded and held in the CR02 capture register. Until the next capture trigger occurs, the value of the CR02
register is held.
A valid edge used as a capture trigger is set using external interrupt mode register 1 (INTM1). When both a
rising edge and falling edge are set as capture triggers, the pulse width of an applied external signal can be
measured. When a capture trigger is generated using one edge, the period of an input pulse signal can be
measured.
For the detailed format of the INTM1 register, see Fig. 11-2 in Chapter 11.
TM0
count value
Count starts
INTC00
interrupt request
INTC01
interrupt request
0H
CE0 ←1
CR00
CR01 CR01
CR00
Cleared Cleared