Part Number: LAUNCHXL-CC2640R2
Other Parts Discussed in Thread: CC2640R2F
I have developed code for ADC conversion for CC2640R2F microcontroller using CC2640R2 launchpad.
I have connected on-board 3.3V supply pin to DIO23 pin. When i compile the adc code in CCS IDE, I got ADC readings on UART terminal window.But there is variations in ADC readings.
I have attached screenshot of ADC readings, multimeter output, and adc code.
Multimeter is showing 3.24V constantly but digital value ie., ADC reading is varying. Why variations of ADC reading happening?
Will ADC readings be vary or constant?
Can any one solve my issue?
I have given files below:
cc2640r2f_adc_code_working.rtf
/*
* Copyright (c) 2015-2017, Texas Instruments Incorporated
* All rights reserved.
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* notice, this list of conditions and the following disclaimer.
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* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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*/
/*
* ======== empty.c ========
*/
/* For usleep() */
#include <unistd.h>
#include <stdint.h>
#include <stddef.h>
/* Driver Header files */
#include <ti/drivers/GPIO.h>
#include <ti/drivers/ADC.h>
#include <ti/display/Display.h>
// #include <ti/drivers/I2C.h>
// #include <ti/drivers/SDSPI.h>
// #include <ti/drivers/SPI.h>
// #include <ti/drivers/UART.h>
// #include <ti/drivers/Watchdog.h>
/* Board Header file */
#include "Board.h"
/* global variableS FOR GUI COMPOSER */
uint16_t adcValue = 0;
/*
* ======== mainThread ========
*/
void *mainThread(void *arg0)
{
/* 1 second delay */
uint32_t time = 100000;
/* Call driver init functions */
GPIO_init();
ADC_init();
// I2C_init();
// SDSPI_init();
// SPI_init();
// UART_init();
// Watchdog_init();
/* Open Display Driver */
Display_Handle displayHandle;
Display_Params displayParams;
Display_Params_init(&displayParams);
displayHandle = Display_open(Display_Type_UART, NULL);
/* Open ADC Driver */
ADC_Handle adc;
ADC_Params params;
ADC_Params_init(¶ms);
adc = ADC_open(Board_ADC0, ¶ms);
if (adc == NULL) {
// Error initializing ADC channel 0
while (1);
}
while (1) {
int_fast16_t res;
res = ADC_convert(adc, &adcValue);
if (res == ADC_STATUS_SUCCESS) {
Display_printf(displayHandle, 1, 0, "ADC Reading %d", adcValue);
}
usleep(time);
}
}
