chipKIT® Development Platform

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I2C bus Frequency

Created Sun, 04 Mar 2012 21:20:22 +0000 by nuxeh


Sun, 04 Mar 2012 21:20:22 +0000


Is there any way to change the I2C bus frequency on a ChipKit? It seems to be 100 kHz by default.

I have tried changing the frequency in the twi.h header file in the MPIDE distribution, which doesn't appear to change the bus frequency, as it does for Arduino.



Mon, 05 Mar 2012 18:28:02 +0000

Which twi.h file did you alter? The one in: \mpide-0022-windows-20111212-test\hardware\pic32\libraries\Wire

or the one in:


The first should be the correct one for the Chipkit.


Mon, 05 Mar 2012 22:21:06 +0000

Aha! Yes, that solved it. I had never thought there was a separate set of libraries for the PIC32 architecture, but it makes quite a lot of sense that there is.

It even seems to work for a 1 MHz bus speed. Very nice indeed.

Thanks for your help, dangeljs