RTOS/CC2640R2F: How can I use “i2cTx()” in Sensor Controller Studio for read and write value from MPU6500

user5889149

Prodigy 10 points

Part Number: CC2640R2F

Tool/software: TI-RTOS

I.m trying to get MPU6500 connect to cc2640r2-LAUNCHXL using SCS

this is the help doc about i2cTx:

//////////////////////////////////////////////////////

i2cTx

Prototype: i2cTx(txValue)

Transmits a single byte over I2C. The received acknowledgment value is stored in state.i2cStatus.

Parameter value(s)

txValue - The value to be transmitted

////////////////////////////////////////////////////

And these is a example:

//////////////////////////////////////////////////

Examples

Accelerometer Polling

// Accelerometer (I2C address 0x86+W): Write X register address (0x04)

i2cStart();

i2cTx(0x86 | I2C_OP_WRITE);

i2cTx(0x04);

// If successful ...

if (state.i2cStatus == 0x0000) {

    // Accelerometer (I2C address 0x86+R): Read X/Y/Z register values

    i2cRepeatedStart();

    i2cTx(0x86 | I2C_OP_READ);

    i2cRxAck(output.x);

    i2cRxAck(output.y);

    i2cRxNack(output.z);

i2cStop();

// Handle errors, if any ...

if (state.i2cStatus != 0x0000) {

    ... Handle errors ...

} 
//////////////////////////////////////////////////////////////

so how to locate I2c address and register address by using i2cTx to read and write from sensor?

I can not find useful example for my project.

over 6 years ago

0 AB over 6 years ago

TI__Mastermind 23556 points

Hello,

See below for an example on how to write to a device with ADDRESS (ALS_I2C_ADDR) and Writing a 16bit value (ALS_CFG_ONE_SHOT) to a register location (ALS_REG_CFG).

Execution Code

// Configure and start the next measurement
i2cStart();
//This sends the address + write bit
i2cTx(I2C_OP_WRITE | ALS_I2C_ADDR);
//This sends register address you wish to write to
i2cTx(ALS_REG_CFG);
//This send the MSB value you wish to write to the register location
i2cTx(ALS_CFG_ONE_SHOT >> 8);
//This send the LSB value you wish to write to the register location
i2cTx(ALS_CFG_ONE_SHOT >> 0);
i2cStop();

// Read the result after ~100 milliseconds + a 20% margin
evhSetupTimer1Trigger(0, 120, 2);

// Schedule the next execution
fwScheduleTask(1);

Event Handler A Code

// If a measurement was successfully started during the last execution ...
if (state.i2cStatus == 0x0000) {
    
    // Select the result register
    i2cStart();
    //This sends the address + write bit
    i2cTx(I2C_OP_WRITE | ALS_I2C_ADDR);
    //This sends register address you wish to write to
    i2cTx(ALS_REG_RESULT);
    
    // If successful ...
    if (state.i2cStatus == 0x0000) {
        U16 resultRegH;
        U16 resultRegL;
        
        // Read the result
        i2cRepeatedStart();
        //This sends the address + read bit    
        i2cTx(I2C_OP_READ | ALS_I2C_ADDR);
        //This reads the first byte value and saves it in resultRegH
        i2cRxAck(resultRegH);
        //This reads the second byte value and saves it in resultRegH
        i2cRxNack(resultRegL);
        i2cStop();
    } else {
        i2cStop();
    }
}

I hope this helps,

Bluetooth®︎

Bluetooth forum

RTOS/CC2640R2F: How can I use “i2cTx()” in Sensor Controller Studio for read and write value from MPU6500