2.3 Data Visualizer
Now it´s later ;-) (see Data Visualizer)
We now have the option to display the data both with the "Data Visualizer" and with the LCD. But to do this, you have to make yourself an additional board, on which the display is attached. Of course you can also use a conventional I2C LCD. But, it's slow and you have to program it yourself...
Attention: If you didn´t connect the LCD board, you have to unable the TWI (see line 84 to 89). Of course it is possible to build a programm, which will know if the LCD is connected or not. Perhaps I will do it in the next version...
The advantage of the board is that it has an I2C distributor additionally, to which you can connect up to seven I2C devices. (EAGLE below) For "normal" LCD you need to short out R1 and R3. Some LCD needs to short R2 and R4. Or you solder resistors (0805) with zero ohms.
I'm not going to explain the LCD program, it's too complex. To implement it in other programs, you have to include the header "I2C.h", add the "Init.h" with lines 22 - 26. Then you have to implement lines 121 - 141 in the interrupt service routine "TIMER2_OVF_vect", and of course lines 151 - 178. Good luck!