I set up my laptop with CAN software and linked up to the CAN Bus to get the battery voltage values. I tested each battery voltage and calibrated the CAN data to correspond to the battery voltage. I found the voltages were not changing at first. I think when I last fiddled with the measurement boards I didn't put them back together properly and I was 1 pin out on the connector. I carefully put it all back together and all the voltages were nearly right. I gave them a tweak using the calibration trimmers on the board so the hexadecimal values were representing the actual voltage measured for each of the 10 batteries. Unfortunately the display has a noisy power supply connection or a bad earth or something like that and I am getting some mush on the screen. It worked fine when it was powered from the USB port on my laptop, but when I hook up to the car, then it is glitchy. That's my next problem to solve. The image below is the background screen from the screen design program.
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The actual display in the car with real data is much nicer than in the picture. The camera has picked up an interference pattern and reflections of my finger taking the picture amongst other things. slowly, but surely it is getting better and better. I also have the overall voltage working now so I can potentially get rid of the motor controller programmer box sticking out of the trim as I am just using this to monitor the battery pack voltage in general. I shall fix the noisy power supply issue first.