GD32W51x User Manual
460
Figure 17-15. Output-compare in three modes
CEN
CNT_REG
00
01
02
03
04
05
.
62
63
Overflow
match toggle
CNT_CLK
OxCPRE
00
01
02
03
04
05
.
62
63
01
02
03
04
05
.
00
match set
match clear
OxCPRE
OxCPRE
PWM mode
In the output PWM mode (by setting the CHxCOMCTL bits to 3
’
b110 (PWM mode0) or to 3
’
b
111(PWM mode1), the channel can generate PWM waveform according to the TIMERx_CAR
registers and TIMERx_CHxCV registers.
Based on the counter mode, we can also divide PWM into EAPWM (Edge aligned PWM) and
CAPWM (Centre aligned PWM).
The EAPWM period is determined by TIMERx_CAR and duty cycle is determined by
TIMERx_CHxCV.
Figure 17-16. Timing chart of EAPWM
shows the EAPWM output and
interrupts waveform.
The CAPWM period is determined by 2*TIMERx_CAR, and duty cycle is by
2*TIMERx_CHxCV.
Figure 17-17. Timing chart of CAPWM
shows the CAPWM output and
interrupts waveform.
If TIMERx_CHxCV is greater than TIMERx_CAR, the output will be always active under PWM
mode0 (CHxCOMCTL==3
’
b110).
And if TIMERx_CHxCV is equal to zero, the output will be always inactive under PWM mode0
(CHxCOMCTL==3
’
b110).