I would like to add a sensor package to my BR2 that monitors the hydraulics for a manipulator arm I’m trying to build. It has a small controller that reads various inputs, and displays them on a small OLED display. The problem is the display is driven by I2C. I’d like to send the I2C data up a spare tether pair so I can connect the display at the surface. I’ve scoured the Internet, and failed to come up with a solution for a tether length of 100m or more. I’ll be using two arduinos (Master-Slave/RS485) to control the thing, I’m wondering if there is a way to leverage them?
I2C is designed to only go a few centimeters, there’s no way to send it up the tether directly.
Capture the data in the ROV, and send it out on a different communication interface, then spit it back out on I2C the way you got it. You could do this perhaps with the arduino you are already using. I think this would be a non-trivial endeavor.
Get the actual data that is being displayed on the oled (the values themselves, not the positions of the pixels), and send that up to the surface and deal with it how you want, perhaps just printing it out on your computer.
Do you have any documentation for the hydraulic system? Are you tied to the OLED?
I think this is your best bet. Try to find the model of the temp and pressure sensor, or what the interfaces is (analog voltage signal?). There are also similar sensors and displays that you can buy individually and be sure of how they operate. On the surface, you can receive the data with an arduino, or your computer and display it on the i2c display or your computer.