topic Re: K60 ADC's value read problem in Kinetis Microcontrollers

K60 ADC's value read problem

kkkk — Wed, 28 May 2014 06:44:10 GMT

I enable ADC1_DP1 & ADC2_DP0. I get the ADC key value by my code successfully. But I don't know how to enable multi-ADC pins, such as ADC1_DP1,ADC1_DP3,ADC1_SE18,ADC1_SE23. How do I get each single ADC pin value? Here is my code. Thanks a lot.

void api_ADC_Init(void)

{

SIM_SCGC3 |= SIM_SCGC3_ADC1_MASK;

ADC1_SC3 |= 0x80;//ADC1 self-calibration

while(ADC1_SC3&0x80)

_time_delay(100);

ADC1_CFG1 = ADC_CFG1_ADICLK(0) | ADC_CFG1_ADIV(1) | ADC_CFG1_MODE(2);

ADC1_SC2 = 0x00;

ADC1_SC1A = 0x41;//ADC1_DP1

SIM_SCGC6 |= SIM_SCGC6_ADC2_MASK;

ADC2_SC3 |= 0x80;//ADC2 self-calibration

while(ADC2_SC3&0x80)

_time_delay(100);

ADC2_CFG1 = ADC_CFG1_ADICLK(0) | ADC_CFG1_ADIV(1) | ADC_CFG1_MODE(2);

ADC2_SC2 = 0x00;

ADC2_SC1A = 0x40;//ADC2_DP0

}

SystemStatus api_GetADCValue(api_ADCChannel_t B_ADCChennel, WORD *Wp_ADCValue)

{

SelectADCConvertChannel((api_ADCChannel_t) B_ADCChennel);

cl_ForceDelay_us(15);

if ((B_ADCChennel == api_ADC_CH1)&&(ADC1_SC1A&ADC_SC1_COCO_MASK ))

{

*Wp_ADCValue = ADC1_RA;

ADC1_SC1A = 0x41;//initiate a new conversion

return OK;

}

if ((B_ADCChennel == api_ADC_CH2)&&(ADC2_SC1A&ADC_SC2_COCO_MASK ))

{

*Wp_ADCValue = ADC2_RA;

ADC2_SC1A = 0x40;//initiate a new conversion

return OK;

}

cl_ForceDelay_us(1);

return NO_DATA;

}

Re: K60 ADC's value read problem

Hui_Ma — Thu, 05 Jun 2014 02:31:04 GMT

It need to modify ADC Status and Control Registers 1 (ADCx_SC1n) [ADCH] bits to select the input ADC channel.

There is another way, which using DMA to help ADC do a scan work (multi channels can be sampled and conversion), more detailed info, please check below link:

http://cache.freescale.com/files/32bit/doc/app_note/AN4590.pdf

Wish it help.

best regards,
Ma Hui

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Re: K60 ADC's value read problem

samz — Thu, 03 Jul 2014 10:32:08 GMT

Generally, it trigger the ADC conversion, then check the status, read the ADC register when it finish conversion.

I use processor expert to generate ADC code, it seems not make sense.

The PE setting for ADC are:

Discontinuous Mode ===>yes

Static sample groups ===>Enabled

After generating code, it only have three function:

Init - LDD_TDeviceData* ADC_InputPS_Init(LDD_TUserData *UserDataPtr);

CreateSampleGroup - LDD_TError ADC_InputPS_CreateSampleGroup(LDD_TDeviceData *DeviceDataPtr,...

GetMeasuredValues - LDD_TError ADC_InputPS_GetMeasuredValues(LDD_TDeviceData *DeviceDataPtr,...

===========================================================================================

I can't find how to use CreateSampleGroup() to trigger and check status, is there any example for how to use the ADC?

Re: K60 ADC's value read problem

Hui_Ma — Fri, 04 Jul 2014 05:29:25 GMT

Hi Sam,

Please let us know which Kinetis product you are using?

Wish it help.

best regards,
Ma Hui

Re: K60 ADC's value read problem

samz — Sat, 05 Jul 2014 01:42:14 GMT

The MCU is MK60DX256VLL10.

Re: K60 ADC's value read problem

Hui_Ma — Thu, 10 Jul 2014 03:09:39 GMT

Hi Sam,

You can download K60 example code from below link:

KINETIS512_V2_SC : Kinetis 100MHz Rev 2 Example Projects.

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=K60_100&nodeId=01624698C9DE2DDDAF&fpsp=1&tab=Design_Tools_Tab

It includes ADC example code.

Wish it help.

best regards,
Ma Hui