Ooops. I think I fried my Seq

[mongrol]

I've been moving my battlestation back into my Cave this weekend after it was vacated by a "visitor". Unfortunately in my rush I plugged my SEQv4 into a 7.5v supply which I use to power the majority of my kit. Every light came on with no display. After realising my error and going back to the proper 5v supply I have the same result. Every LED on the CS lights up, no display or response otherwise.

Have I fried my Disco board?

[latigid on]

Probably  

You might want to check if you can use the USB ports and "re-flash," but I'd say she's a gonner. I think if the ST link side still works you can use it as a standalone programmer.

[mongrol]

It's toast. Good job these things are only $30.

[mongrol]

So my new DISCO arrived today and it does the same thing. Disconnected everything (OLED, MIDIIO, CS) and left it on the Core board and the same. No response from it. Remove Disco from the Core and it appears correctly in MIOS Studio. It appears a component on my Core board is fried. Time to follow the schematics. :)

[Antichambre]

Hi Mongrol,

Just check the two IC on your mbhp, remove it and try again. Change the guilty one. Maybe one is shorting the power and passing the usb protection switch in faulty mode.

Best regards
Antichambre

[mongrol]

Muha! Language is a beautiful thing.

The new discovery board I received was a MB997D. I was going down the Core page verifying my build when I noticed there was a firmware update to make the new model D run from USB. Downloaded from ST.com, flashed and it works!

TK: On the core page it states the new firmware is untested. This isn't true now. :)

Now to put this bloody orange box back together for the LAST time.

[mongrol]

CS goes in J8/9 right?

[latigid on]

Yes. If unsure about the orientation of the IDC, (before applying power) test for continuity on the 5V line e.g. the power pins of the shift registers vs. 5V pin on the Discovery Board.

[mongrol]

Hmm, so all the buttons work, both Oled's still light up correctly but I get about 2/3's of the CS led's permanently lit. I've updated the hw cfg file to match the firmware and tried all permutations of 5v/3v/ext/usb/oled's disconnect etc so I'm sure it's not a wavering voltage issue.

[latigid on]

You can try swapping U8 (74HC595). U7 would seem to be okay if the matrix responds to buttons. To confirm: this was working at one point?

Also, ensure the CS is connected by J1, closer to the centre of the board, not J2 below it.

Edited December 1, 2016 by latigid on

[mongrol]

Since I don't have any spare lying around I swapped U7 and U8. This resulted in no LED's working and only half the buttons. Fried chips then? I might go order plenty tomorrow.

[latigid on]

Good plan.