ADC configuration for ADC1_7 pin

lpcware — Wed, 15 Jun 2016 19:01:55 GMT

Content originally posted in LPCWare by LPC_beginner on Sun Jun 23 04:30:32 MST 2013

I am very new to LPC43xx series processors. My problem is with reading ADC using a specific channel.

After going thorough the user guide and examples provided, I have come up with following steps.

/* get scu base */
p = (LPC_SCU_Type*)(LPC_SCU_BASE);

* Select ADC function

*/
p->ENAIO1 |= 0x80; //Enable ADC function for ADC1_7 (pad PF_7 in BGA256 package)

/*
* Disable internal pullup
  * Disable internal pull down
* Select  function as GPIO
*/
   p->SFSPF_7 = 0x14; // Is this configuration is correct??


/* Set GPIO as input mode */
GPIO_SetDir(GPIO_PORT_7,(1<< 21), INPUT_MODE);

/* disable band gap option */
p->ENAIO2 = 0;

/* ADC initialize */
ADC_Init(LPC_ADC1, 200000, 10); /* Initialize ADC1 */
/* Disable ADC Interrupt *
ADC_IntConfig(LPC_ADC1,ADC_ADINTEN7,DISABLE);

ADC_ChannelCmd(LPC_ADC1,ADC_CHANNEL_7,ENABLE);
ADC_StartCmd(LPC_ADC1,ADC_START_NOW);
/*

* Wait for conversion to complete

   */
  while (!(ADC_ChannelGetStatus(LPC_ADC1,ADC_CHANNEL_7,ADC_DATA_DONE)));
  ADC_val = ADC_ChannelGetData(LPC_ADC0,ADC_CHANNEL_7);

}

I have measured the pad PF_2 which is having voltage of 1.56, but I always get 0 in adc register.

Verified that DONE bit is getting set after the adc conversion start.

Do I missed any initialization.

Appreciate any pointers on this issue...

topic ADC configuration for ADC1_7 pin in LPC Microcontrollers

ADC configuration for ADC1_7 pin