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Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@mgg1010
Hi
I've been attaching my Espruino board to my existing I2C busses which have previously been tested with Arduino and other devices.
One interesting question is bus voltage: the I2C devices I'm using are on PCBs that require a 5V power supply. In the past, I've connected up a 3.3v Arduino - I just used pullups to 3.3v instead of 5v, and this worked. But it didn't work work with Espruino.
Then I realized that the Espruino pins used for I2C are 5V tolerant, so I've changed the pullup to connect to 5v - and it seems to work now :)
However, I am using 2k7 pullups, which I suspect may be a bit too low. I think the general advice is 4k7 to 10k?
Thoughts?