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How do I enable ADC0 input trigger on FRDM_K64F

Question asked by Mark Haines on Oct 14, 2014
Latest reply on Nov 4, 2014 by Mark Haines

In Processor Expert, I'm using the ADC_LDD Component with DMA1 for a FRDM-K64F.  I selected PDB0 as trigger since I wanted to use the external trigger (PDB0_EXTTRG pin), but I got no samples. Using method AD0_StartLoopMeasurement( ) instead of AD0_StartLoopTriggeredMeasurement( ) (i.e. an untriggered data acquisition) I get 256 samples in my input buffer, taken at back-to-back conversion rate.  So, everything works but the trigger. I turned on the PDB0 interrupt and set Debug breakpoint and sure enough the PDB counted down and the ADC should have seen the trigger.  I thought the PDB might be the problem and selected the PIT timer as the ADC trigger, and even though the PIT interrupt can blink an LED, the ADC never gets a trigger.  I initialized with AD0_Init().  I have done a similar setup on the TWR-K20D50M chip (simpler ADC), and had no problems. Either I'm missing how to enable the trigger or I have a defective device.  Any hints?

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