AM6548: How to get ADC working on AM65xx_IDK Dev Board

Part Number: AM6548

Hello,

I'm trying to get ADC running on AM65xx_IDK Eval Board. For now I only found an example in <pdk>/packages/ti/diag/adc. Are there any other sources or even binaries? I cannot make this example to get any binary for debugging.

Until now I do the following in my source code (the code is mostly copied from <pdk>/packages/ti/diag/adc/src/adc_test_v2.c :

- call "BoardDiag_initADC" with the base address of ADC0. Which itself calls ADCClearIntrStatus() , ADCPowerUp(baseAdr,True) & ADCInit(baseAddress, FALSE, 0U, 0U)

- call ADCEnableIntr(adcBaseConf.baseAddress, (ADC_INTR_SRC_END_OF_SEQUENCE | ADC_INTR_SRC_OUT_OF_RANGE))

call

adcConfig.mode = ADC_OPERATION_MODE_SINGLE_SHOT;
adcConfig.openDelay = 0x1U;
adcConfig.sampleDelay = 0U;
adcConfig.rangeCheckEnable = 0U;
adcConfig.averaging = ADC_AVERAGING_NONE;
adcConfig.fifoNum = ADC_FIFO_NUM_0;
adcConfig.channel = static_cast<uint32_t>(channel);

configStatus = ADCSetStepParams(adcBaseConf.baseAddress,
            adcConfig.channel, &adcConfig);

where channel is the channel I want to read. For beginning I want to read only one channel

Then I get to start conversion:

- call ADCStepEnable(baseAddress, channel, TRUE);    adcStart(baseAddress);

After that and some time I want to read the value:

- call

intrStatus = ADCGetIntrStatus(adc[i].baseAddress);
while(!(ADC_INTR_SRC_END_OF_SEQUENCE == (intrStatus & ADC_INTR_SRC_END_OF_SEQUENCE)))
{
       intrStatus = ADCGetIntrStatus(.baseAddress);
}
fifoWordCnt = ADCGetFIFOWordCount(baseAddress, ADC_FIFO_NUM_0);
fifoData = ADCGetFIFOData(baseAddress, ADC_FIFO_NUM_0);

Is this implementaion correct? Or do I need to call something else?

Wiring:

I connected the middle pin of a poti to ADC0_Ch0. Poti is connected to GNC and 1.8V. For now I don't have a reference voltage connected. Poti is configured to provide something in the middle between GND & 1.8V.

Is it necessary to connect reference voltage to the pin header? Or does the SoC get some reference voltages internaly?

I assume I should get at least some changes in the digits. But I get only 0 or FFF depending of the poti state. But it is more like a hysteresis.

Also I don't understand the "Steps" of ADC. Whats is that in this case? Are these the channels? Would be nice if you could write more context in your manuals!!

Kind regrads

Andreas