One of the guys at work was asking me if I would have a look at his field scale to see what was going on. It refused to turn on anymore and they are worth a few bucks.
It's a surprisingly simple device really, just a big ol load cell in there with a little transmitter board and MCU to transmit to the hand-held remote to read the weight.
I pulled it apart and checked the power lines, seems we have power going through the "on" switch and power is getting to the MCU. Nothing seems burned or shorted.
So, I'm wondering now since I don't have enough knowledge in this stuff, could it be the crystal not letting the MCU boot up? What else could prevent the system from booting up? It appears to have power going where it needs to and shorting the "start" switch isn't enough. I think the chip is getting a signal but I don't know if it would be the chip or something simple. I'm taking a guess at the crystal since this thing sees some rough use (tossed around a bit, vibration, etc). There is nothing but traces on the back, and the contact switch points.
Anyone have some tips for me to narrow down the issue? Hopefully I can save him a few bucks since this seems not terribly trivial. I have a scope and such as well.
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