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A word of warning about other dev boards...

Posted: Mon Sep 23, 2013 11:27 am
by dciliske
So, I'm currently working on a side project at home (designed around the SBL2E chip) for a LED driver/controller board. In the process of this, I've decided to use a STM8 for some additional A/D and to offload the averaging. I got the eval board on Friday and spent some time getting things up and running on Saturday. When I got to the point of programming the board, I couldn't communicate with the board; "Ok, somethings wrong with the driver/software tools setup". So, I get out my STM32 discovery board which I've played with some before and had working previously and try to get that to work.

In the process of doing all this, I drop the STM32 board onto my oscilloscope's ground connector, and short the power to earth ground. And my PC turns off. Ok, so I shorted out my USB port, that was dumb. Guess I'll reboot. Oh, my computer is still off. And it won't POST. And it says somethings wrong with the memory. And maybe the motherboard is fried. Really? I thought this wasn't supposed to happen with USB devices?

Oh, the ST eval boards don't have input fuses? How? I thought that was a requirement of USB devices? Be very careful with eval boards and I guess use an externally powered USB hub if you need to hook them up and they don't have an Vbus fuse.

TL/DR: Accidently dropped an STM32 dev board onto my oscilloscope ground probe and fried some major component(s) on my home PC, because ST didn't put an input fuse on the Vbus line per spec.

Oh, and before people ask, yes this fuse exists on Netburner dev boards. It's the (green) 1206 package labeled 'F' next to the USB port.

-Dan

Re: A word of warning about other dev boards...

Posted: Mon Sep 23, 2013 11:34 am
by tod
Thank you for the warning, and for taking one for the team!