The IIC clock defaults to 100kb, need to increase it to ~200kb.

I've tried:

  • changing the constant TWI_CLOCK and rebuilding Wire.cpp
  • calling initMasterWIRE(200000) after Wire.begin().

I'm using a scope to verify the change, and thus far can't seen a change in the clock width.

I believe the pull resistors are 10k? Might need to decrease a bit to.

Looking for a very short example! TIA.


Looking for a very short example!


1) find out the mcu used by the board;

2) look up its datasheet;

3) go to the i2c section and find the register(s) that control the i2c clock speed;

4) change it/them.

alternatively, you can take a look at the i2c initialization code and go from there.

the likely solution will be a one liner: use a mask to clear bits and then set those bits depending on your desire i2c speed.

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