Vfrdtyky

When I try to use i2cset on my raspberryPI with mode for SMBus block data it is saying Error: Adapter does not have SMBus block write capability.

# sudo i2cset -y 3 0x20 0x01 0xDE 0xAD 0xC0 0xDE 0x00 0xFF s

Error: Adapter does not have SMBus block write capability

I looked at the WiringPi code and it has 2 functions to write data on I2C. The first uses byte data and the second a word data. It is missing the (SMBus block data) and the (I2C block data). So I suppose that RaspberryPi's do not support it.

I want to implement a C++ code that write a double to the i2c on my raspberryPi. To write an int I am already doing.

root@sense4:~/i2c-tests# sudo i2cset -y 3 0x20 0x00 0x1f

root@sense4:~/i2c-tests# sudo i2cget -y 3 0x20 0x00

0x1f

C++ code:

int I2CTools::write8(int value) {

    union i2c_smbus_data data;



    data.byte = value;



    return i2c_smbus_access(i2cFileDescriptor, I2C_SMBUS_WRITE, 0x00, I2C_SMBUS_BYTE_DATA, &data);

}

int I2CTools::read8() {



    union i2c_smbus_data data;



    if (i2c_smbus_access(i2cFileDescriptor, I2C_SMBUS_READ, 0x00, I2C_SMBUS_BYTE_DATA, &data))

        return -1;

    else

        return data.byte & 0xFF;

}

Now I suppose that I have to loop over the address like this:

root@sense4:~/i2c-tests# sudo i2cset -y 3 0x20 0x00 0x1f ; sudo i2cset -y 3 0x20 0x01 0x85 ; sudo i2cset -y 3 0x20 0x02 0xeb ; sudo i2cset -y 3 0x20 0x03 0x51 ; sudo i2cset -y 3 0x20 0x04 0xb8 ; sudo i2cset -y 3 0x20 0x05 0x1e ; sudo i2cset -y 3 0x20 0x06 0x09 ; sudo i2cset -y 3 0x20 0x07 0x40

root@sense4:~/i2c-tests# sudo i2cget -y 3 0x20 0x00 ;sudo i2cget -y 3 0x20 0x01 ; sudo i2cget -y 3 0x20 0x02 ; sudo i2cget -y 3 0x20 0x03 ; sudo i2cget -y 3 0x20 0x04 ; sudo i2cget -y 3 0x20 0x05 ; sudo i2cget -y 3 0x20 0x06 ; sudo i2cget -y 3 0x20 0x07

0x1f

0x85

0xeb

0x51

0xb8

0x1e

0x09

0x40

But in C++ of course... Is this make sense for you? I am newbie with i2c devices and I suppose it is this direction that I have to do in my code. Thanks!

int I2CTools::writeDouble(double value) {

    union i2c_smbus_data data;



    doubleToCharArray.original = value;



    std::cout << "nBytes: ";

    for (unsigned long address = 0; address < sizeof(double); address++) {

        std::cout << (int) doubleToCharArray.output[address] << ' ';

        data.byte = (int) doubleToCharArray.output[address];

        // std::cout << hex(doubleToCharArray.output[address]) << ' ';

        i2c_smbus_access(i2cFileDescriptor, I2C_SMBUS_WRITE, address, I2C_SMBUS_BYTE_DATA, &data);

    }

    return 0;

}

double I2CTools::readDouble() {



    unsigned char charArray[sizeof(double)];

    std::cout << "nBytes: ";

    for (unsigned long address = 0; address < sizeof(double); address++) {

        union i2c_smbus_data data;

        if (i2c_smbus_access(i2cFileDescriptor, I2C_SMBUS_READ, address, I2C_SMBUS_BYTE_DATA, &data)) {

            return -1;

        } else {

            std::cout << (int) data.byte << ' ';

            charArray[address] = data.byte;

        }

    }

    return *reinterpret_cast<double *>(charArray);

}