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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.
@d0773d
I purchased: http://www.atlas-scientific.com/_files/_datasheets/_circuit/pwr-iso.pdf? That power isolator seemed a bit expensive, however, I wanted to experiment with an already made power isolate; sinse I already purchased: http://www.atlas-scientific.com/_files/_datasheets/_circuit/pH_EZO_datasheet.pdf? I figured I would purchase the Power Isolator from the same company.
Anyways, I'm not that technical when it comes to reading datasheets and I would like advice/help on how to properly connect everything up to the Espruino, power iso and the PH sensor(http://www.atlas-scientific.com/_files/_datasheets/_circuit/pH_EZO_datasheet.pdf?)
I already asked a question about what size pull-up resisters to use which are 4.7k. I contacted the manufacturer and asked if there are pull up resisters on the power isolator board and if the 4.7k would interfere with the power isolator. The manufacturer explained to me that there are pullup resisters on the board and the 4.7k might be too high.
The power isolator requires 5v in and will output 5v. I know the Espruino is 3.3v so I was planning to use a seperate 5v power adapter and a L7805 voltage regulator to provide a cleaner 5v to the power isolator. Will I be required to use a logic converter between the Espruino i2c and the power isolator i2c since the Espruino is 3.3v and power isolator is 5v? I was planning to use: https://www.adafruit.com/products/757 if a logic converter is necessary.
I need help designing my circuit because I am confused about the pullup resisters. The power isolator and logic converter have 10k pullups and the ph datasheet asks for a 4.7k pullup value for i2c communication. What values of pullups are required and where do I place them in the circuit?