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#include "Drivers/I2C_Communication/I2C.h"
#include <driverlib/sysctl.h>
#include <driverlib/rom_map.h>
#include <inc/hw_memmap.h>
#include <driverlib/i2c.h>
#include "include.h"
//#include "Common/Sys_Configuration/Configuration.h"
#define CONFIG_REGISTER_ADDRESS 0x01
#define LSB_BITMAP_CONFIGURATION_OF_CONFIG_REG 0x83
#define MSB_BITMAP_CONFIG_REG_SAMPELING_CHANEL_A0 0xc4
#define MSB_BITMAP_CONFIG_REG_SAMPELING_CHANEL_A1 0xd4
#define MSB_BITMAP_CONFIG_REG_SAMPELING_CHANEL_A2 0xe4
#define MSB_BITMAP_CONFIG_REG_SAMPELING_CHANEL_A3 0xf4
#define START_DATA_DELAY 1500
#define READ_DATA_DELAY 1000
#define END_DATA_DELAY 100000
#define SLAVE_ADDRESS_1 0x48
#define SLAVE_ADDRESS_2 0x4a
#define SLAVE_NUM_OF_CHAN 4
#define I2C_FIRST_CHANNEL_ADDR 0xc3
#define START_WRITING_TO_CONFIG_REG_IN_SLAVE 0x01
#define START_READ_FROM_CONVERSION_REG_IN_SLAVE 0x00 //read sampled results
void InitI2C(void)
{
//
MAP_SysCtlPeripheralReset(SYSCTL_PERIPH_I2C3);
//
// Stop the Clock, Reset and Enable I2C Module
// in Master Function
//
MAP_SysCtlPeripheralDisable(SYSCTL_PERIPH_I2C3);
MAP_SysCtlPeripheralReset(SYSCTL_PERIPH_I2C3);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C3);
//
// Wait for the Peripheral to be ready for programming
//
while(!MAP_SysCtlPeripheralReady(SYSCTL_PERIPH_I2C3));
//
// Initialize the I2C master module.
//
I2CMasterInitExpClk (I2C3_BASE, SYS_CLK_FREQ, true);
//
MAP_SysCtlPeripheralReset(SYSCTL_PERIPH_I2C4);
//
// Stop the Clock, Reset and Enable I2C Module
// in Master Function
//
MAP_SysCtlPeripheralDisable(SYSCTL_PERIPH_I2C4);
MAP_SysCtlPeripheralReset(SYSCTL_PERIPH_I2C4);
MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_I2C4);
//
// Wait for the Peripheral to be ready for programming
//
while(!MAP_SysCtlPeripheralReady(SYSCTL_PERIPH_I2C4));
//
// Initialize the I2C master module.
//
I2CMasterInitExpClk (I2C4_BASE, SYS_CLK_FREQ, true);
}
//each entry into the function reads result from one sampled channel in the USB
void SampleI2CData(uint32_t* resultData)
{
uint8_t _resultData[2];
static uint8_t _currSlaveAddress = SLAVE_ADDRESS_1;
static uint8_t _currChannel = 0;
uint8_t dataIndex = 0;
// modulo calculation used to take specific channel from ADC each time - channel 0,1,2,3
_currChannel = (_currChannel+1) & 0x3;
//if finished reading first ADC channels , reset the channel index to next ADC
if ((_currSlaveAddress == SLAVE_ADDRESS_2) && (_currChannel == 3))
{
_currChannel = 0;
}
// reset slave addres to next ADC card
if (_currChannel == 0)
{
_currSlaveAddress = (_currSlaveAddress == SLAVE_ADDRESS_1) ? SLAVE_ADDRESS_2 : SLAVE_ADDRESS_1;
}
//calculate index of where to write result data in the resultData array
dataIndex = (_currSlaveAddress == SLAVE_ADDRESS_2) ? SLAVE_NUM_OF_CHAN + _currChannel : _currChannel;
// Send slave address and config reg address
I2CMasterSlaveAddrSet (I2C0_BASE, _currSlaveAddress, false);
I2CMasterDataPut(I2C0_BASE, START_WRITING_TO_CONFIG_REG_IN_SLAVE);
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_SEND_START);
SysCtlDelay(1500);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
// while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
//Send MSB of config reg to current slave
uint32_t chanAddr = I2C_FIRST_CHANNEL_ADDR + 0x10*_currChannel;
I2CMasterDataPut(I2C0_BASE, chanAddr);
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_SEND_CONT);
SysCtlDelay(15000);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
// while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
//Send LSB of config reg to current slave
I2CMasterDataPut(I2C0_BASE, 0xe3);
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_SEND_FINISH);
SysCtlDelay(15000);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
// while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
// Send slave address and conversion reg address (reg for reading results)
I2CMasterSlaveAddrSet (I2C0_BASE, _currSlaveAddress, false);
I2CMasterDataPut(I2C0_BASE, START_READ_FROM_CONVERSION_REG_IN_SLAVE);
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_SINGLE_SEND);
SysCtlDelay(15000);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
//while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
// Start Read from configured slave
I2CMasterSlaveAddrSet(I2C0_BASE, _currSlaveAddress, true);
I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_BURST_RECEIVE_START);
SysCtlDelay(15000);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
// while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
//each read result is represented in 16 bit this why we read twise
//each time in 8 bits
//read MSB byte
_resultData[0] = I2CMasterDataGet(I2C0_BASE);
I2CMasterControl(I2C0_BASE, I2C_MASTER_CMD_BURST_RECEIVE_FINISH);
SysCtlDelay(15000);
// while (!(I2CMasterBusy(I2C0_BASE))); //Wait till end of transaction
// while (I2CMasterBusy(I2C0_BASE)); //Wait till end of transaction
//read LSB byte
_resultData[1] = I2CMasterDataGet(I2C0_BASE);
//concutenate 2 reads of 8 bytes into one read of 16 bytes
resultData[dataIndex] = _resultData[0] << 8 | _resultData[1];
}
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