SparkFun Forums

[tbriseb]

Hi there,

I am trying to do a design where I am taking an MSP430 Demo board with LCD that already has a RTC which displays the time on it. What I am trying to do is every few minutes output a PWM signal that will drive a DC motor driver. The problem is that the interupt for the PWM comes, it screws up the RTC since it's processing the PWM interupt.

Is there a way to make both interoperable together?
I guess I can increase the DCO for quicker processing of the interupt and then hope I can do what needs to be done in less than 1 second to guarantee that it doesn't affect the RTC.

Does anyone have any other ideas?

Thanks
Todd

[OldCow]

Timers (or other peripherals) can work simultaneously. But if they need CPU to service interrupts, they need to tolerate interrupt latencies caused by all interrupts. PWM interrupts are usually very simple and does not take much CPU time, and RTC usually can tolerate long latencies. I do not see any problem.

[tbriseb]

Thanks for the clarification. After some digging into the code I realized I had some other stuff going on which affect the I/O port being used as TA PWM output.

Thanks
tB