UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 230

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

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(a) Processing when count is started
(b) Processing when count value is read
Figure 8-12 To Distinguish Whether One or No Valid Edge Has Been Input with External Event Counter
Read TM0 contents
Count value read
AX AX+1
AX TM0
AX = 0 ?
End
NO
Clear INTP3 interrupt
request flag
YES
CHAPTER 8 TIMER/COUNTER 0
Start count
Start count
CE0 1
; Assign the number of input valid edges to AX register
PIF3 0
End
YES
PIF3 = 1 ?
; Clear PIF3 to 0
; Set CE0 to 1
NO
; Check TM0 value
If 0, check interrupt
request flag
; Check PIF3 contents
If 1, there is a valid
edge