Oh, you've been busy. Thanks heaps for that, I like your treatment of the ADC west components, much better than what I had.
If possible I would like to not have to change the program. The intention is to use the ISEE program
here , it seems to give me what I want (a time stamped data log file) and some limited calibration possibilities. Most calibration will be done offline, in Excel but there is a very simple control language that in the ISEE program that I'm going to try and use as well. Could also be used to control the fan actually.
This means that I do not want to change the IO distribution too much, my programming ability is close to zero and I don't want the time for me to learn to be another implementation delay.
I am rerouting the digital spagetti a bit though, inspired by your treatment of it.
Edit: Looking closer at your version I suddenly realised what you've been driving at. Brilliant. Simple and obvious on reflection. Another one of what you are full of Groth.
But I will keep the ADC steering signals the same as the original, otherwise your suggestions are the bees knees.