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« on: December 17, 2015, 06:23:34 pm »
Plugged my Zeus into power one last time before bringing it inside for troubleshooting and only channel 2 was dead the rest were static green/purple. My first thought was "I bet the channel 2 PIC is bad."
So I pull it out of socket first thing and everything else works fine. So I replaced it with the PIC from channel 16 and ran the utility set the string numbers, etc. (When you move a PIC it will keep it's old string data so you have to run the utility again.)
So yes, 1 bad PIC can lock up all the channels. I suspect because they all share the same data bus from the 485 IC. I don't use PICs much anywhere else so don't know all of their details and haven't looked up info, pinout on this particular chip.
At this point I'm thinking the power supply is part of the issue - brownout, startup or otherwise. Typically these little 8 or 16 bit micros, whether PIC, Atmel or other, are used in embedded systems that will have some local power supply regulation. I wonder if having a local regulator on board (that took power from the 12v supply and regulated down to the 5v) instead of running from the 5v of the ATX power supply directly wouldn't avert this issue. Unfortunately this board doesn't have the "handles" to make that an easy mod.
It might be interesting to know exactly what model of power supply people are using that haven't had any issues.
My power supply is a Logisys 480W, PS480D2 that I think I bought from MCM Electronics a few year's ago.