Part Number: TMS320F28379D
Hello experts,
in my application I have to run the time-base submodule in up-down-count mode.
At the time points 1, 2, 1, 2, ... (see picture) the interrupt routine MyInterrupt() should be triggered.
The event for interrupt at time point 1:
Time-base counter equal to compare B register (CMPB_1) when the timer is incrementing.
The event for interrupt at time point 2:
Time-base counter equal to compare B register (CMPB_2) if the timer is decrementing.
Because I can only set one event as interrut source in the event trigger submodule, I have the following in mind to trigger the interrupts in the time points 1 and 2.
At time 1, at the beginning of the interrupt routine MyInterrupt():
Counter-Compare B shadow register = CMPB_2
ETSEL[INTSELCMP] = 0
ETSEL[INTSEL] = 111
At time 2, at the beginning of the interrupt routine MyInterrupt():
Counter-Compare B shadow register = CMPB_1
ETSEL[INTSELCMP] = 0
ETSEL[INTSEL] = 110
The loading of Counter-Compare B register from its shadow register ist done when Time-Base counter is equal to zero or period (TBCTR = 0x00 || TBCTR = TBPRD).There must be no problem here.
My question is about updating register ETSEL. Is it possible to update this register "on the fly" as I have described above. Can there be problems or unpredictable behavior here?
Thank you in advance for your reply - Bui
