NEC 78K0 Series User Manual page 275

<5> By performing procedures <3> and <4> repeatedly, a pulse with an arbitrary duty can be obtained.
<6> To stop the count operation, set TMHEn = 0.
If the setting value of the CMP0n register is N, the setting value of the CMP1n register is M, and the count
clock frequency is f
CNT
• PWM pulse output cycle = (N + 1)/f
• Duty = (M + 1)/(N + 1)
Cautions 1. The set value of the CMP1n register can be changed while the timer counter is operating.
However, this takes a duration of three operating clocks (signal selected by the CKSn2 to
CKSn0 bits of the TMHMDn register) from when the value of the CMP1n register is changed
until the value is transferred to the register.
2. Be sure to set the CMP1n register when starting the timer count operation (TMHEn = 1) after
the timer count operation was stopped (TMHEn = 0) (be sure to set again even if setting the
same value to the CMP1n register).
3. Make sure that the CMP1n register setting value (M) and CMP0n register setting value (N) are
within the following range.
00H ≤ CMP1n (M) < CMP0n (N) ≤ FFH
Remarks 1. For the setting of the output pin, see 9.3 (3) Port mode register 1 (PM1).
2. For details on how to enable the INTTMHn signal interrupt, see CHAPTER 19
FUNCTIONS.
3. n = 0, 1
CHAPTER 9 8-BIT TIMERS H0 AND H1
, the PWM pulse output cycle and duty are as follows.
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Preliminary User's Manual U17260EJ3V1UD
INTERRUPT
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