I am looking to use a HT0740 breakout board for a project but cannot work out how I’m supposed to control it. It says it’s compatible with arduino but no instructions on what commands to send is given. I’ve tried going through the python library but came up short. How do I control this from an arduino?
It’s electronically compatible, as in it will work. If “you” can find an Arduino library for it.
The TCA9554A is likely what you going to need to get working first.
Also keep in mind it likely uses 3.3V logic as that’s what a Pi uses. Some Arduino’s use 5V logic and some use 3.3v logic.
It uses I2C to communicate and is compatible with 5v devices (acording to the product page). How can I find out what commands to send over I2C to toggle the relay or the LED?
I take “3.3V or 5V compatible” to mean you can power it via 3.3v or 5V. I don’t think that will have any effect on the logic level used on i2c though, it will still be 3.3v logic.
The python commands are there for on off. You’d have to use an IDE that works with python or micropython and arduino.
mu comes to mind.
Installing Mu Editor | Welcome to CircuitPython! | Adafruit Learning System
And Adafruit may be the place to go for info on how to get this to work. They do a lot more stuff with microcontrollers etc than Pimoroni do.