UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 352

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

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If a value equal to or less than the TM2 value is written to CR20 before the CR20 and TM2 match, the duty of that
PPG cycle will be 100 %. CR20 rewriting should be performed by the interrupt due to a match between TM2 and CR20.
TM2
Count Value
Remark ALV2 = 0
Caution If the PPG cycle is extremely short as compared with the time required to acknowledge an interrupt,
CR20
TO2
0H
the value of CR20 cannot be rewritten by interrupt processing that is performed on match between
TM2 and CR20. Use another method (for example, to poll the interrupt request flags in software
with all the interrupts masked).
Figure 10-32 Example of 100 % Duty With PPG Output
CR21
n1
CHAPTER 10 TIMER/COUNTER 2
n1
CR21
n2
n3
When value n2 which is smaller than the TM2 value n3 is
written to CR20 here, the duty of this period will be 100 %.
n1
CR21
n2
n2
CR21
n2