Interfacing a Sensor Hub with TWI drivers?

[polimarte]

Hi,

I am trying to adapt the read register function that use the TwoWire lib of Arduino in order to read a Sensor Hub Response Byte of a defined Host Command :

uint8_t readByte(uint8_t _familyByte, uint8_t _indexByte,\
                                           uint8_t _writeByte)
{

    uint8_t returnByte;
    uint8_t statusByte;

    _i2cPort->beginTransmission(_address);
    _i2cPort->write(_familyByte);
    _i2cPort->write(_indexByte);
    _i2cPort->write(_writeByte);
    _i2cPort->endTransmission();
    delay(CMD_DELAY);

    _i2cPort->requestFrom(_address, sizeof(returnByte) + sizeof(statusByte));
    statusByte = _i2cPort->read();
    if (statusByte)// SUCCESS (0x00)
        return statusByte; // Return the error, see: READ_STATUS_BYTE_VALUE 

    returnByte = _i2cPort->read();
    return returnByte; // If good then return the actual byte. 

}

to have a function that uses the nrf_dr_twi, like this: 

uint32_t nrf_drv_read_registers(uint8_t reg, uint8_t* p_data, uint32_t length)
{
    uint32_t err_code;
    uint32_t timeout = OXI_TWI_TIMEOUT;

    err_code = nrf_drv_twi_tx(&m_twi_instance, OXI_ADDRESS, &reg, 1, false);
    if (err_code != NRF_SUCCESS) return err_code;

    while ((!twi_tx_done) && --timeout) ;
    if (!timeout) return NRF_ERROR_TIMEOUT;
    twi_tx_done = false;

    err_code = nrf_drv_twi_rx(&m_twi_instance, OXI_ADDRESS, p_data, length);
    if (err_code != NRF_SUCCESS) return err_code;

    timeout = OXI_TWI_TIMEOUT;
    while ((!twi_rx_done) && --timeout) ;
    if (!timeout) return NRF_ERROR_TIMEOUT;
    twi_rx_done = false;

    return err_code;
}

Have you some ideas on how i can use the family and index byte of the Sensor Hub in order to retrieve the correct byte? 

Thank you very much in advance,

Kind regards

[awneil]

polimarte said:

Arduino

Note that Arduino is not supported by Nordic - you need to go to the Arduino forums for Arduino support.

polimarte said:

how i can use the family and index byte of the Sensor Hub in order to retrieve the correct byte?

What does the documentation for this unspecified "Sensor Hub" tell you?

Note that the "Sensor Hub" neither knows nor cares what microcontroller you use, so this is all down to the particular "Sensor Hub - not specific to the microcontroller.

[Karl Ylvisaker]

Hello Polimarte,

Have you some ideas on how i can use the family and index byte of the Sensor Hub in order to retrieve the correct byte? 

It is as @awneil says - we do not support Arduino, unfortunately.
However, as awneil mentions, I would recommend reading the Sensor Hubs documentation, to figure out how to implement the interface.
It will be easier for you to see what the Sensor Hub is expecting to receive from its datasheet, rather than reading it and translating it directly from an Arduino implementation.

Best regards,
Karl

[awneil]

Karl Ylvisaker said:

I would recommend reading the Sensor Hubs documentation, to figure out how to implement the interface.

Absolutely!

That is always the basic first step in interfacing to any device!

How To Interface Anything To Anything Else

And don't forget to look at the Product Page on the manufacturer's websites:  that is where the manufacturers will present all their supporting collateral - including datasheets, application notes, example code, etc: 

https://www.avrfreaks.net/commen...

 

https://www.avrfreaks.net/commen...

 

Again, this is a key first step in working with any new part.

[Karl Ylvisaker]

If I could have upvoted your answers twice, or otherwise highlighted your answers here I definitely would have, @awneil !


Best regards,
Karl

[awneil]