Hi
i am reading ADC121S101CIMF using spi but i not getting correct value at some different voltage .which is mention in below file. and input given by potentiometer ( 5 k ohm ) in analog pin of adc
1.output file
2 block diagram of setup
spi code:
/**
* Copyright (c) 2015 - 2018, Nordic Semiconductor ASA
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* 3. Neither the name of Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "nrf_drv_spi.h"
#include "app_util_platform.h"
#include "nrf_gpio.h"
#include "nrf_delay.h"
#include "boards.h"
#include "app_error.h"
#include <string.h>
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#define SPI_INSTANCE 0 /**< SPI instance index. */
static const nrf_drv_spi_t spi = NRF_DRV_SPI_INSTANCE(SPI_INSTANCE); /**< SPI instance. */
static volatile bool spi_xfer_done; /**< Flag used to indicate that SPI instance completed the transfer. */
#define TEST_STRING "Nordic"
//static uint8_t m_tx_buf[] = TEST_STRING; /**< TX buffer. */
//static uint8_t m_rx_buf[sizeof(TEST_STRING) + 1]; /**< RX buffer. */
//static const uint8_t m_length = sizeof(m_tx_buf); /**< Transfer length. */
/*
uint8_t m_tx_buf[255] = {1,2,3,4,5,6,7,9,10,11,12,13,14,15,16,17,18,19,20,8};
uint8_t m_rx_buf[255] = {0};
uint8_t m_length =255;
*/
uint8_t m_tx_buf[2] = {0,0};
uint8_t m_rx_buf[2] = {0};
uint8_t m_length =2;
uint8_t spi_data[8] = {0,0,0,0,0,0,0,0};
uint8_t spi_data1[8] = {0,0,0,0,0,0,0,0};
uint8_t spi_data2[8] = {0,0,0,0,0,0,0,0};
uint8_t spi_data3[8] = {0,0,0,0,1,0,1,1};
//uint8_t m_rx_buf[255] = {0};
//uint8_t m_length =255;
uint16_t rxbuff[255];
/**
* @brief SPI user event handler.
* @param event
*/
void spi_event_handler(nrf_drv_spi_evt_t const * p_event,
void * p_context)
{
spi_xfer_done = true;
//NRF_LOG_INFO("Transfer completed.");
if (m_rx_buf[0] != 0)
{
//NRF_LOG_INFO(" Received:");
//NRF_LOG_HEXDUMP_INFO(m_rx_buf, strlen((const char *)m_rx_buf));
}
}
int read_aadc_data()
{
uint16_t output=0;
uint8_t lsb[1]={0};
volatile uint8_t msb[2]={0,0};
uint8_t data[2]={0,0};
uint8_t data1[2]={0,0};
//nrf_gpio_pin_clear(SPI_SS_PIN);
spi_xfer_done = false;
APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi,&data[0],2,msb,2));
while (!spi_xfer_done)
{
// NRF_LOG_FLUSH();
__WFE();
}
// printf("msb=%d\n",msb[0]);
// printf("msb=%d\n",msb[1]);
output = ((msb[0] << 8)|msb[1]);
//nrf_gpio_pin_set(SPI_SS_PIN);
/*
APP_ERROR_CHECK(nrf_drv_spi_transfer(&spi,&data1[0],1,lsb,1));
while (!spi_xfer_done)
{
// NRF_LOG_FLUSH();
__WFE();
}
printf("lsb=%d\n",lsb[0]);
nrf_gpio_pin_set(SPI_SS_PIN);
//nrf_gpio_pin_clear(SPI_SS_PIN);
output=0;
output = ((msb[0] << 8)|lsb[0]);
//nrf_delay_us(1);
// printf("output=%d\n",output);
*/
return output;
}
int main(void)
{
nrf_drv_spi_config_t spi_config = NRF_DRV_SPI_DEFAULT_CONFIG;
spi_config.ss_pin = SPI_SS_PIN;
spi_config.miso_pin = SPI_MISO_PIN;
spi_config.mosi_pin = SPI_MOSI_PIN;
spi_config.sck_pin = SPI_SCK_PIN;
APP_ERROR_CHECK(nrf_drv_spi_init(&spi, &spi_config, spi_event_handler, NULL));
int i=0;
while(1)
{
uint16_t adcOut=0;
float value=0.0;
memset(data_buff,0,344);
adcOut=0;
adcOut=read_aadc_data();
printf("%d,",adcOut);
/*
i=i+1;
if(i==10)
{
printf("\n");
i=0;
}
*/
//nrf_delay_ms(1000000);
nrf_delay_us(500);
}
}
can you guide why i am getting multiple value and wrong value and same data reading from arduino board i am getting correct value .
BR
DG
