Hi,
I'm using microC/OS on MSP430F1611 and have used semaphores in all of my SPI functions. Both the spi Tx and Rx use DMA.
I have an 8 channel external ADC and I want to sample my channels at some rate using interrupt and Timer B. But I can't request a semaphore in ISR.... So I was wondering if anyone has a good idea of implementing a stable sample rate on an external ADC while using microC/OS tasks (I don't need to use timers if there is a more efficient method.)
Thanks a lot.
The best way to do that is drive the ADC's start-conversion pin from the timer output pin, and drive an external interrupt from the ADC's end-of-conversion pin. That way you're controlling the sampling with a hardware timer.
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I'm using ADS8345 which triggers a conversion whenever SPI receives one byte. So to sample a channel, I write a byte to SPI. So I'm not sure how to implement your method... Please advise
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