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Posts: 126
Hi Guys

I've noticed a few issues with my overhead panel over time and thought that as I'm going to be off work over xmas, I should address it.

My switches run off 4 Bodnar Cards, all my LEDS run from Arduino and mobiflight, everything works almost perfectly. I have a few ghost switches (turning on & off themselves within the sim) which I am assuming is a bad wire.

I've had a look at the back of the board and wish I spent more time when I was building it, its just a jumble of wires.

I have saw that I used a GRND wire to connect to ALL my switches...………….. Is this the problem? Should I perhaps split them into groups, so all the engine switches are connected together to a grnd pin on Ardiuno


I use a 12v PSU at the back to power the LED Strip Lights for back lighting.. Should I run a ground wire from that to go all the switches?

Whats best practice to ground so many switches?

NO issues with the LEDS, only switchs / Toggles
2019-11-21 16:13
From: ETSI, Germany
Posts: 3867
At first there is a confusing part.....

You say you make the Inputs by LeoBodnars..... But you also say you wire GRD from all switches to the Arduinos.
Basicly if you have indipendet systems then the GRD of Switches must go to GRD of Leo Bodnars.

In Simple words.... The GRD of a Element ( Like a switch) must get to the same GRD as the Dataline or 5V Line is come from ( Or to the same potential)

So you have 2 ways....
You can share all GRD lines from all element of each SINGLE board..... For example on Leo Bodnar Board 1 are 30 Switches..... So share the GRD from THESE 30 Switches to ONE Point and connect it to THAT Leo Bodnar Board.
Simply do it like Stephan say and connect all your Boards together by a single wire that go From Board1 GRD to Board 2 GRD to Board 3 GRD and so on.

Then its no longer important where you connect a GRD from a switch ( or a combinded ground of xx switches) ..... When Dataline come from Board1 you can now set GRD line also in Board 2,3,4,5 and so on cause ALL Boards have now the same GRD Potential ( in case of your shared bypass)

NOTE: The GRD of your LED Backlight Suply i would NOT share here..... Cause this is completly indipendend and not need to be combined in the system. If i understand right its just for the strips and nothing else.
Good Luck !
2019-11-21 16:55
Posts: 5
Hello everyone.
I cannot solve issue related to overhead electrical panel (AC/DC meters) segment displays.
On the top meter i have connected one segment display of 8 digit and on the lower i connected 2 segment displays of total 12 digits.
After setting up all offsets all seems to work normal and then top side stops responding and turns off while lower side still works normal.
I have to reset arduino and mobiflight and after start up all is on but again after one minute top side turns off....

Please help....
2019-12-16 21:22
From: ETSI, Germany
Posts: 3867
Lots of possible issues.

Wire problem..... Electrical Limits reached..... Broke Parts ..... Wrong Config Logic ( Error in a special condition) .

You must simply try out a bit......

For example show a clear and 100% correct thing on the Displays..... For testing show Com1, Com2 Nav 1 Nav 2 etc.
Does error occure again..... Then its a Hardware problem.

For testing you can connect the Max Chips different..... If they are in a Chain connect them for testing each single.... Maby the outout pins are broke.
Maby just a little wriggle contact. Get sure all wires are solder and in 100% perfect conditions.

Without see your system i would say..... 90% a hardware and/or wire problem.
Good Luck !
2019-12-17 03:03