UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 305

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

(3) Up to 1 count clock is required after an operation to start timer/counter 1 (CE1
(4) While an instruction that writes data to the compare register (CR1n: n = 0, 1) is executed, a match between CR1n, to which
(5) A match between timer register 1 (TM1) and compare register (CR1n: n = 0, 1) is detected only when TM1 is incremented.
1 actually starts (refer to Figure 9-30).
For example, when using timer/counter 1 as an interval timer, the first interval time is delayed by up to 1 clock. The second
and those that follow are at the specified interval.
the data is to be written, and timer register 1 (TM1) is not detected.
Write data to CR1n when timer/counter 1 is executing counting operation in the timing that the contents of TM1 do not match
the value of CR1n before and after writing (e.g., immediately after an interrupt request has been generated because TM1
and CR1n have matched).
Therefore, the interrupt request is not generated even if the same value as TM1 is written to CR1n.
Count Clock
TM1
CE1
Figure 9-30 Operation When Counting Is Started
CHAPTER 9 TIMER/COUNTER 1
0
Count Start Command (CE1
by Software
Timing to Start Actual Counting
0
1
1) has been performed before timer/counter
1)
2
3
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