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Old 04-16-2014, 04:30 PM   #30 (permalink)
mechman600
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I am still quite new to all of this, so some of the concepts you speak of are still beyond my brain. What I did find is that my POT voltage readings (having been read, ADC'ed, converted to PWM, sent down a wire, counted, converted to a float, and displayed on my LCD) seem to be quite stable and accurate.

I realize that PWM out is only 8 bits. However, since I am sending the values of smaller integers (the math to figure out individual voltages being done in the slave/reader Arduino), we are dealing with a value that does not require the same resolution. For example, we are measuring a bank of 8 lithiums with 10 bits @ 4.5V * 8 = 36V / 1024 = 0.035V resolution. We are then sending each cell voltage across comm with 8 bits @ 4.5V / 256 = 0.02V resolution. No resolution lost.

I do hear what you are saying about converting again and again, and that makes perfect sense. However, I see nothing erratic or inaccurate when I test. But, I shall test more, with more inputs and through an opto, because an opto will also be a necessary ingredient when coupling multiple boards at different locations on the pack's series string.
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