I use FTM to configure PWM combined.
When the PWM module controls burping, the duty cycle of the first wave on and the last wave off is random. Two PWM circuits do not switch simultaneously.
waveform：
Hiccup control：
if(flag == 1) //“flag” changes before 0 and 1
{
FTM0->SC &= 0xFF0FFFF; //disable pwm ch 0123
}
else
{
FTM0->SC |= 0x00F0000; //enable pwm ch0123
}
FTM0->SYNC |= 0x80;
PWM configuration：
I want both PWM circuits to switch on and off simultaneously with the same duty cycle。thanks。
Hi WEIFAN,
Sorry, can you tell me what or what is the relationship between C1 and C4?
C1 and C4 seems not in Complementary mode, otherwise the channel (n+1) output should be the inverse of the channel (n) output.
Seems that you are using FTM_SC[PWMENn] control the value of channel output. But it will disable or enable the output immediately after you write to the register, it will not wait for FTM_CNT=CNTIN to change the output.
Sorry I may not understand what kind of PWM waveform you expect to generate? Is it convenient to draw your desired waveform on the oscilloscope waveform graph?
Have a look at 47.5.15 Software Output Control Mode, do the channel (n) and channel (n+1) output after the software output control shown in Figure 47-74 is the waveform what you want?
Best Regards,
Robin
Hi，
I am very happy to receive your reply.
Sorry, I didn't find the waveform I needed。
As shown in the above figure,CH1-CH4 is enable or disable at the rising or falling edge to ensure complete duty cycle。
Figure 2，I drew a waveform myself。
Best Regards,
WeiFan
