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//ADS1018 Configuration
//http://www.ti.com/lit/ds/symlink/ads1018.pdf
//Page 19-20
// |(1=Start Single-shot), (0=no effect)
// |
// | |Mux (000 = P is AIN0 N is AIN1, 001 = P is AIN0 N is AIN3, 010 = P is AIN1 N is AIN3 , 011 = P is AIN2 N is AIN3
// | | 100 = P is AIN0 N is GND, 101 = P is AIN1 N is GND, 110 = P is AIN2 N is GND, 111 = P is AIN3 N is GND)
// | |
// | | |PGA Gain (000 = ±6.144V, 001 = ±4.096V, 010 = ±2.048V, 011 = ±1.024V, 100 = ±0.512V, 101,110,111 = ±0.256V)
// | | |
// | | | |Mode (0 = Continuous conversion mode, 1 = Power-down and single-shot mode (default))
// | | | |
// | | | | |Data Rate (000 = 128SPS, 001 = 250SPS, 010 = 490SPS, 011 = 920SPS, 100 = 1600SPS, 101 = 2400SPS, 110 = 33005SPS, 111 = not used))
// | | | | |
// | | | | | |Sensor Mode (1=Internal Temp Mode, 0=ADC Mode)
// | | | | | |
// | | | | | | |PullUp (0 = Pullup resistor disabled on DOUT/DRDY pin, 1 = Pullup resistor enabled on DOUT/DRDY pin (default))
// | | | | | | |
// | | | | | | | |Update Config (01 = Valid data, update the Config register (default), 00,11,10 = do not update config register)
// | | | | | | | |
// | | | | | | | | |You must Always Write a 1 to this bit
// | | | | | | | | |
// 1 000 010 1 110 1 1 01 1 = 1000010111011011 = 0x85DB (this sets up a single shot for the internal temperature sensor 3300SPS)
// 1 100 101 1 110 0 1 01 1 = 1100101111001011 = 0xCBCB (this sets up a single shot for single ended AIN0, PGA 0.256V, 860SPS)
// 1 000 101 1 110 0 1 01 1 = 1000101111001011 = 0x8BCB (this sets up a single shot for differnetial AIN0 AIN1, PGA 0.256V, 860SPS)
#include <bcm2835.h>
#include <stdio.h>
#include <unistd.h>
int main(){
if (!bcm2835_init())
return 1;
bcm2835_spi_begin();
bcm2835_spi_setBitOrder(BCM2835_SPI_BIT_ORDER_MSBFIRST);
bcm2835_spi_setDataMode(BCM2835_SPI_MODE1);
bcm2835_spi_setClockDivider(BCM2835_SPI_CLOCK_DIVIDER_256);
bcm2835_spi_chipSelect(BCM2835_SPI_CS1);
bcm2835_spi_setChipSelectPolarity(BCM2835_SPI_CS0, LOW);
char txMSB[1], txLSB[1], rxMSB[1], rxLSB[1], configMSB[1], configLSB[1] ;
txMSB[0] = 0x85;
txLSB[0] = 0xDB;
rxMSB[0] = 0x00;
rxLSB[0] = 0x00;
configMSB[0] = 0x00;
configLSB[0] = 0x00;
printf("Intitial values \nmsb = %2.2X \nlsb = %2.2X\n", txMSB[0], txLSB[0]);
// int counter = 0;
// for (int i =0 ; i <100 ; i++){
while(1){
bcm2835_spi_transfernb(txMSB, rxMSB, 1);
usleep(350);
bcm2835_spi_transfernb(txLSB, rxLSB, 1);
usleep(350);
bcm2835_spi_transfernb(txMSB, configMSB, 1);
usleep(350);
bcm2835_spi_transfernb(txLSB, configLSB, 1);
printf("\nData \nmsb = %2.2X \nlsb = %2.2X \nconfig \nmsb = %2.2X \nlsb = %2.2X\n", rxMSB[0], rxLSB[0], configMSB[0], configLSB[0]);
}
printf("\nData \nmsb = %2.2X \nlsb = %2.2X \nconfig \nmsb = %2.2X \nlsb = %2.2X\n", rxMSB[0], rxLSB[0], configMSB[0], configLSB[0]);
bcm2835_spi_end();
bcm2835_close();
return 0;
}
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