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Noamko / Quad-Copter

Prototype quad copter
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No need to wait after Wire.requestFrom(). #1

Open Koepel opened 6 years ago

Koepel commented 6 years ago

In the file "Quad-Copter/QuadM3/IMU.cpp" there is waiting after the Wire.requestFrom(). You may remove the "while(SWire.available() < 14);" and all the "while(!SWire.available()) {};" after a Wire.requestFrom(), regardless which (software) Wire library you use. Explanation: Common-mistakes#1

Noamko commented 6 years ago

Thank you for your comment Koepel! the Issue has been fixed.

Koepel commented 6 years ago

I think I did not look at it very well the first time. In the function "readRegister16()" and "readRegister24()" there is a Wire.beginTransmission() and Wire.endTransmission() around the Wire.requestFrom(). However, the Wire.beginTransmission() and Wire.endTransmission() should only be use when writing data. Explanation: Common-mistakes, number 2 and 3.

I also prefer not to shift a 8-bit variable 8 bits to the left. The compiler will solve that, so it will work.

For example:

uint16_t IMU::readRegister16(uint8_t reg)
{
    SWire.beginTransmission(MS5611_ADDRESS);
    SWire.write(reg);
    SWire.endTransmission();

    SWire.requestFrom(MS5611_ADDRESS, 2);
    uint16_t value = SWire.read();
        value <<= 8;
    value |= SWire.read();

    return value;
}