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/**
* Maxim ADC has not so suitable default settings after startup.
* So we will create init function to tune this ADC.
*/
#include <stdlib.h>
#include "ch.h"
#include "hal.h"
#include "max1236.h"
#define max1236_addr 0b0110100
/* Data buffers */
static i2cblock_t max1236_rx_data[MAX1236_RX_DEPTH];
static i2cblock_t max1236_tx_data[MAX1236_TX_DEPTH];
/* ADC results */
static uint16_t ch1 = 0, ch2 = 0, ch3 = 0, ch4 = 0;
/* Error trap */
static void i2c_max1236_error_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
(void)i2cscfg;
int status = 0;
status = i2cp->id_i2c->SR1;
while(TRUE);
}
/* This callback raise up when transfer finished */
static void i2c_max1236_cb(I2CDriver *i2cp, const I2CSlaveConfig *i2cscfg){
(void)*i2cp;
(void)*i2cscfg;
/* get ADC data */
}
/* ADC maxim MAX1236 config */
static const I2CSlaveConfig max1236 = {
i2c_max1236_cb,
i2c_max1236_error_cb,
};
/**
* Initilization routine. See datasheet on page 13 to understand
* how to initialize ADC.
*/
void init_max1236(void){
/* this data we must send via IC to setup ADC */
max1236_tx_data[0] = 0b10000011; /* config register content. Consult datasheet */
max1236_tx_data[1] = 0b00000111; /* config register content. Consult datasheet */
/* transmit out 2 bytes */
i2cAcquireBus(&I2CD2);
i2cMasterTransmit(&I2CD2, &max1236, max1236_addr, max1236_tx_data, 2, max1236_rx_data, 0);
i2cReleaseBus(&I2CD2);
}
/* Now simply read 8 bytes to get all 4 ADC channels */
void read_max1236(void){
i2cAcquireBus(&I2CD2);
i2cMasterReceive(&I2CD2, &max1236, max1236_addr, max1236_rx_data, 8);
i2cReleaseBus(&I2CD2);
ch1 = ((max1236_rx_data[0] & 0xF) << 8) + max1236_rx_data[1];
ch2 = ((max1236_rx_data[2] & 0xF) << 8) + max1236_rx_data[3];
ch3 = ((max1236_rx_data[4] & 0xF) << 8) + max1236_rx_data[5];
ch4 = ((max1236_rx_data[6] & 0xF) << 8) + max1236_rx_data[7];
}
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