JA PCB flickering

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Hi,
i’m in the JA PCB test phase now. I’m running the midibox NG, i’ve loaded the seq_l file but the JA PCB is irraticaly flickering.
I’ve tested the cables with the wirescanner. Everything is fine.
I doublechecked all soldering pads. All fine.
But all the leds on the JA are lit and are very jumpy when i touch or move the pcb.
What could be wrong???

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dijf you used the correct ic n rn1?

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dijf all the leds on the JA are lit and are very jumpy when i touch or move the pcb

I also had intermittent issues with JA, it turned out to be a solder dry joint (switch or LED - can’t remember), it took me a couple of attempts to get it stable - CHECK AGAIN?

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mangoest yes, i did (maybe i fried it with soldering?)

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Check as well if any LEDs are broken or have the wrong polarity (also diodes).

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latigid on i,ve tested all the leds and the diodes are soldered in well

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dijf Can you send in a video to make it visual? So we all understand what is happening.

It flickers directly when you hook it all up or only when you loaded the seq_l ? This would exclude if it is HW or maybe processor issue…

Maybe I fried it?
What is the temperature you sued maybe to solder?
If you look at the datasheet of the IC RN1 there you see how much the maximum temperature is that it can handle during X time. Check that first of course…

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dijf

Does the RN have the correct orientation?
Do any other shift registers in the chain work, i.e. the next boards?
Do you get proper DIN events on button presses? Does the encoder work?
Is the power supply stable?

mangoest mangoest is right: some sort of visual check (photo or video of the board/soldering) would make sense

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How can i add a video? the dialog box says i can’t import mp4

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from the moment i set debug on in MIOS, lights go randomly weird and the encoder doesn’t respond

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I see files are restricted to 9Mb i think. Try maybe to add a video from for example youtube or something?
Orientation is ok for all IC’s?

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Rear ICs seem to have the correct orientation.
I’m not sure about the RN though. Check also that the type (bussed) is correct, or at least you should have two of the isolated type left from your Mouser order.
Check that soldering is okay here too with no bridges between pads.

The behaviour that you see could be to do with the 165 shift register. Reflow the pins there and make sure that you have ca. +5V on pins 10-14 and 3-6

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latigid on you are right about the RN1 ic . i’ve used an isolated type. How can i have overseen this.
I’ll desolder and correct and i’ll get back with the results 😅

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i encountered a problem with desoldering RN1…the soldering pad of pin 2 came of… so i have nothing left to solder it to. Is there a way to fix this? Or is pin2 not used? or perhaps connected to another pin?

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No worries, it’s not connected to anything 😁
No need to worry about pads 2, 8, 9, 10, 15.

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yes! everything works like a charm now!
Thanks for the advice!
On to the next board

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I’m also having a similar issue with the JA board testing. When actioning button presses I don’t get any response or any feedback in MIOS Studio but if I move the encoder a few clicks I get most of the LED lighting up (bar 2 that I need to replace)

I checked that the IC’s are the correct part no and also correct orientation. Tried cleaning the board with 100% isopropyl which seemed to make the board dirtier if you know what I mean.

Any ideas on what to look at next after I replace the two LED’s that are not working?

Thanks in advance for your assistance