CC2530 ADC problem

Part Number: CC2530

Hi,

I am using a CC2530F128 ADC, and I do not get to read the input (the values is always 0). I have tried using the ADC registers, using TIMAC ADC library and z-stack library and I always get the same result. I also try to read  the temperature sensor and the result is 0. But in all cases, the conversion has been completed because the ADCCON1.EOC is set.

The code for read temperature sensor:

  ADCCON3 = 0x3E;
  while (!(ADCCON1 & 0x80));
  // Use all 14 MSB of adcValue
  ADC_result = ADCL >> 2;
  ADC_result |= ADCH << 6;

The code for read channel 0:

    P0DIR = 0x00;   //todo entradas
    P0SEL = 0xFF;     //todo funcion periferico
    HalAdcSetReference( HAL_ADC_REF_125V );
    ADC_result = HalAdcRead(HAL_ADC_CHN_AIN0, HAL_ADC_RESOLUTION_14);

What it is wrong?

Thanks.

Ruben

Try to refer to sunmaysky.blogspot.tw/.../cc2530-adc-howto-in-ti-z-stack.html

Hi YiKai,

I have used the same code that the example:

HalAdcSetReference( HAL_ADC_REF_125V );
ADC_result = HalAdcRead(HAL_ADC_CHN_AIN0, HAL_ADC_RESOLUTION_10);

And ADC_result is always 0. In fact, I can not modify the variable ADC_result. I have defined as uint16 ADC_result = 0xFF; and In the watch window, I can see the value is 0. If I execute for example de code ADC_result = 1; , the value does not change (It is alway 0). Why have that ocurred?

Thanks.

Ruben

AIN0 is mapped to P0.0. Do you use multimeter to check voltage on it?

Make sure you have configured your pin as ADC, INPUT and as PERIPHERAL.

Below you can find an exemple for an ADC input at pin P0.4.
The ADC is configured to use the AVDD5 as voltage reference and 7bits ENOB setting

//ADC
APCFG = 0x10; //0b00010000; //[0] P0.4 Analog IO
ADCCON1 = 0x33; //0b00110011; //[7] EOC (read_only) | [6] Start_conversion | [5:4] Start Trigger (ADCCON1.ST) | [3:2] reserved (00) | [1:0] reserved (11)
ADCCON2 = 0x80; //0b10000000; //[7:6] AVDD5 REF | [5:4] 7bits | [3:0] Channel | (Single Conversion)

//I/O PINS
P0SEL = 0x3C; //0b00111100; //[7:0] {1}-Peripheral {0}-GPIO
P0DIR = 0xEA; //0b11101010; //[7:0] {0}-Input | {1}- Output

ADCCON2 |= 0x04; //Channel 4

if(ADCCON1 & 0x80) //Check EOC...
var = ADCH; //Read any "dummy" remaining value..

ADCCON1 |= 0x40; //Start Conversion

while( !(ADCCON1 & 0x80)); Wait for EOC

uint16 var;
var = ADCL; //Receive LSB
var |= ((uint16)ADCH << 8); //Receive MSB.
var = var >> 8; //Rotate 8 bits because they are dont care when using 7bits