Problem running TLC5940 and Ds1307 together.

We're working on at Arduino project which includes the LED shield 1.4 (3 x TLC5940) and the Ds1307 clock. Each part works fine separately but not when combined. After what we can track track down, the problem occurs when using the Tlc5940 library for the LED shield and the Wire library to communicate with the Ds1307. The problem is that the controller hangs when calling Wire.endTransmission();.

We have been googling and reading docs but no luck, so any inputs will be much appreciated.

Additional information:

When the LED shield has been initialized, values read from the analog input pins on the Arduino board is false. They seem to pick up some random values. Maybe thats why the clock does not work, since it uses the Wire lib, which uses two analog inputs on the Arduino board for the connection.

These are very specific hardware configurations can you post links to the boards you have. In general there is no reason why they should use the same pins but examine the schematics of both and see if there are common pins. There also might be an issue with both libraries requiring the use of the same timer but without the software of the actual libraries used it is hard to say. Can you also post the code you are using to tie them together, use the # icon when posting code.

Problem solved! For some reason, we started using the multiplex library Tlc5940Mux. Now using the Tlc5940 library instead everything works fine. Sorry for any inconvenience.