View Full Version : Burnt my 7.5 Toast

01-19-2016, 04:04 AM
Hey - Been lurking for a while but time to ask a few questions :D

Ive ended up buying 2 CF7.5s because I think Ive burned one slice of toast :(

Hooking up a switch I may have somehow shorted something, now the Activation switch pin seems permanently
ON. I think I must have killed the input pin diode or something on the uC.

The saber comes on when power is applied, but cannot be turned off again, so I think the pin is permanently closed.

When I do a continuity test on my multimeter between the act. pad and the Gnd pad I get a signal. (with nothing soldered on the pads)
Not sure this is right - I dont want to screw with the 2nd CF by checking on that one the same thing.

If the pin is dead, is there any way I can salvage this board, by some clever hack or something?
If not is Erv or TCSS doing any repairs these days?

BTW this has all been to do a Tri-Cree conversion on my MR ANH Luke , so Ill post a thread separately on that soonish


01-19-2016, 05:28 AM
Hello there, to a fellow Brit. Don't know about Erv but across the pond, Zook is one to ask about repairs. You will need a higher post count to PM him unless FJK can point him to you
It might get a bit pricey to international ship back and forth though

Good luck and MTFBWY :mrgreen:

01-19-2016, 06:31 AM
Hello ! Thanks for the info Greenie.
Maybe one of those guys will take pity on me and point me in the right direction ! :)

Silver Serpent
01-19-2016, 07:41 AM
Since you're in the UK, I'd probably try to contact Erv. You can find his contact info on Plecterlabs.com. If he's not the one to contact for the UK, I'm sure he'll direct you to the correct person.

01-19-2016, 08:16 AM
I know little about how the boards work but here's my two cents: It's possible that you have the board configured to use a normally closed latching switch, and therefore it thinks that it is on when the switch circuit isn't closed. I can test on my CF when I get home, but I'm almost certain that the activation pin is supposed to always be "on", because current is supposed to flow through it as soon as you connect it to ground. Check the config files to see if that is the case.

Jay-gon Jinn
01-19-2016, 09:54 AM
The board comes with a default setting on the switch to be used with a latching style, as NanoRex mentions. You likely need to change that and the CF will work just fine, The correct setting for a momentary switch is "switch=2" in the config file.

03-22-2016, 03:46 PM
Hey thanks all for the suggestions. Sorry for my late reply on this.

I actually have a second CF75 which is working perfectly so to sanity check it wasnt my latching setting,
I swapped the SD cards around, and I still have the same problem.

A continuity test from the Act pad to Gnd pad shows there is a short probably internal to the PIC on the board.
Im not doing this on the good CF lol as I dont want anything to happen to that one :D

Not sure what to do at this point. I guess the internal protection diode on the pin is blown - I must have shorted the pin to the main supply somehow while messing around wiring things up.

Maybe someone in the know can answer but I'd would be lucky if one of the unused pins in the PIC was actually being monitored for act, I could potentially mod-wire it to the act pad.