UPSD3422_06 Datasheet, PDF (179/293 Pages) STMicroelectronics – Turbo Plus Series Fast Turbo 8032 MCU with USB and Programmable Logic

uPSD34xx
Programmable counter array (PCA) with PWM
Figure 60. PWM mode - (x8), fixed frequency
CAPCOMHn
8
CAPCOMLn
ENABLE _{8-bit COMPARATORn} MATCH
OVERFLOW
8
PCACLm
S ^SET Q
R _CLR Q
CEXn
TCMMODEn EINTF E_COMP CAP_PE CAP_NE MATCH TOGGLE PWM1
0
0
0
0
0
PWM0
Note:
m = 0: n = 0, 1, or 2
m = 1: n = 3, 4, or 5
AI07859
27.8
Note:
PWM mode - (x8), programmable frequency
In this mode, the PWM frequency is not determined by the overflow of the low byte of the
Counter. Instead, the frequency is determined by the PWMFm Register. The user can load a
value in the PWMFm Register, which is then compared to the low byte of the Counter. If
there is a match, the Counter is cleared and the Load registers (PWMFm, CAPCOMHn) are
re-loaded for the next PWM pulse. There is only one PWMFm Register which serves all 3
TCM in a PCA block.
If one of the TCM modules is operating in this mode, the other modules in the PCA must be
configured to the same mode or left not to be used. The duty cycle of the PWM can be
specified in the CAPCOMHn Register as in the PWM with fixed frequency mode. Different
TCM modules can have their own duty cycle.
The value in the Frequency Register (PWMFm) must be larger than the duty cycle register
(CAPCOM).
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