Problem with using multiple ADC channels

Pak Hin Wong

Other Parts Discussed in Thread: CC2541

I want to use two ADC channels in cc2541 and keep reading data from those two ADC channels.

But those two results got switched sometimes.

For example,

valueOne = HalAdcRead(HAL_ADC_CHANNEL_3, HAL_ADC_RESOLUTION_8);
valueTwo = HalAdcRead(HAL_ADC_CHANNEL_5, HAL_ADC_RESOLUTION_14);

Sometimes, "valueOne" become channel 5 data. "valueTwo" become channel 3 data.

Is it because the ADC result have not cleared before next conversion??

Thanks,

Hin

over 9 years ago

0 Nathan Siegel over 9 years ago

TI__Genius 10980 points

Hi,

How are these being set multiple times? Are you reading the values on an interrupt? And when one value is wrong, is the other one also always wrong (do they both get the wrong value at the same time)?

-Nathan

0 Pak Hin Wong over 9 years ago in reply to Nathan Siegel

Prodigy 20 points

Thanks for the reply

I set a event for reading adc forever.

Like this

if(events & ADC_EVT ){

Read adc1

Read adc2

return (events); // do not cancel the ADC_EVT

}

Two situations

1. Both switch

2. Both correct

0 Nathan Siegel over 9 years ago in reply to Pak Hin Wong

TI__Genius 10980 points

Hi,

I would suggest using a delay to see if the issue is that the ADC result is not being cleared in time.

-Nathan

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Problem with using multiple ADC channels