Hello, I'm working with Wire library,Arduino Mega and I2C bus (20 and 21 pin), i need to use 3.3 volts i2c devices but SDA and SCL on Mega ever have pull ups to 5v. my ask: Is possible to dissable pull ups on pin 20/21 ? how ?. Level shifter is the only solution? I tried to modify twi.c without…

Arduino Mega I2C pull ups for 3v3

system October 31, 2012, 10:09am 5

yes, I desoldered de on-board resistors and works fine with the other pull ups to 3.3v.

regards