Hi,
I hv a LED project that need to control 8 Nano that drives 12 digital pins.
The shortest distance is 2m away and the furthest is 8m away ...
Need some advise on :-
What is Max distance for I2C ?
Will it help to increase the range is I hv I2C pullup resistors at all the 8 I2C slaves ?
Any other protocols can I use if I hv exceed the max distance of I2C protocol ?
Thanks
Rule of thumb : about 0.5 meters to 2 meters for I2C. That is the total length of every piece of wire that is connected to SDA (and the same for SCL).
Others will say a few meters with a Cat6 cable, but I prefer a reliable I2C bus.
The resulting pullup value of all parallel pullup resistors should be calculated. It may not be too low and too high is not good either. If each module has a pullup or just one, that depends on the cable. The default is a single pullup resistor at the Master.
Yes, there are special chips for long range I2C. Or some kind of serial communication like RS-485.
Please use "have" instead of "hv". English is not my native language and I have been looking at "hv" :o , which I read as "high voltage". I was wondering what your plan was with a high voltage pullup resistor, and your question seems to be what happens when you exceed that high voltage.