Author Topic: Dead ETD PIC  (Read 1215 times)

Offline lrhorer

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Dead ETD PIC
« on: March 05, 2016, »
I obtained a used DLA EtherDongle from one of the forum members, but it is DOA.  I tried re-flashing the PIC, but the controller can't even find it.  I verified the setup is good by flashing another ETD with no problems, at all, but every operation with the PICKit 3 fails on the new board.  I cleaned the board thoroughly and inspected the traces, but I don't see any evident solder bridges, cold solder joints, lifted pads, or cut traces.  Unless I am missing something, that pretty much leaves the PIC itself.  I wonder if anyone in DLA land has an SMD reworking station and woud be willing to take a stab at replacing the PIC?

Offline packetbob

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Re: Dead ETD PIC
« Reply #1 on: March 05, 2016, »
I have a diy reflow oven and have access to a reflow workstation..
I would be happy to take a stab at it...
However I am in Canada so shipping might be a bit more $$$ both ways....

Offline packetbob

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Re: Dead ETD PIC
« Reply #2 on: June 16, 2016, »
It took me a while to get to it but I have replaced the PIC chip on lrhorer's EtherDongle using a hot air rework station...
The chip is now able to be programmed (and verified) and I have loaded the DMX code on it to test...

However I ran into a couple issues that I want to figure out before I go any quicker:
1) Both the 5v and 3.3v regulators get quite hot. I have powered the board off of a power supply set for 8.5 volts and it draws 340 mA. Does anyone know what the normal current draw would be. Just want to get a sanity check before I go any further.

2) When I connect it to an Ethernet switch port neither of the magic jack leds light up. However the port led on the Ethernet switch does light up. I have confirmed the resistors for the magic jack leds are 240 ohm. Any hints on further troubleshooting?

I have started looking through the various postings btu thought I'd throw this post in the event someone had some quick solutions..

Thanks

Offline packetbob

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Re: Dead ETD PIC
« Reply #3 on: June 16, 2016, »
Problem(s) solved...

Looks like the regulators are fine as long as you keep the input voltage low..  When I ran it at 7.0 volts both seemed fine

Looks like the problem with the MagJack leds was cold solder joints on the Ethernet chip. The give away was that the leds would light intermittently when I flexed the board a bit (actually noticed this completely by accident) I retouched all the chips leads with a small tip and lots of flux..

Now I can stream data to all 4 universes with the DMX code..