UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 306

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

(6) When using timer/counter 1 as an external event counter, the status where no valid edge is input cannot be distinguished
266
from the status where only one valid edge has been input, by using timer register 1 (TM1) alone (refer to Figure 9-31),
because the contents of TM1 are 0 in both the cases. To make a distinction, use the interrupt request flag of INTP0, as
shown in Figure 9-32.
Figure 9-31 Example Where Whether One or No Valid Edge Has been Input Cannot Be
Distinguished with External Event Counter
INTP0
TM1
Count Start
0
Cannot be
Distinguished
CHAPTER 9 TIMER/COUNTER 1
0
1
2