Large number of flickering/ghost inputs on Master Cards

[fordgt40]

Jack

The IDC connectors can sometimes cause poor connections. When you swopped mastercards did you swop the connecting cables as well? If so, try it again but leave the cables in place and just move the card. That should help determine if it is the cable or card that is prompting the problem.

Good luck

David

[Boeing 747 Flyer]

Hi David,

That's a good point, I think that'll be my next move. Unfortunately to do that will take a fair bit of work as the cables are bound to the structure of the "stack" (I never envisioned something like this happening!); so all that will have to be dismantled, but I think given the problems it was inevitable anyway.

Jack

[iwik]

Jack,
I am wondering if you are getting some form of cross talk between output and input. Wiring to Leds will have digital switched levels and this if in close proximity to inputs make cause a problem. If you were to separate boards as you are thinking of doing to trouble shoot then just doing this may give you a fix. Just my 2cents worth.
Les

[Boeing 747 Flyer]

Hi Les,

Thanks for your response.

Yes, I think given the level of problems we are going to dismantle the stack and separate the cards out one by one, clean them of any dust, etc, etc.

On another note, do you have any more specific information about how the input/output logic works on the master cards? Perhaps it would be useful to know what defines an "ON" condition, perhaps the interference from the outputs is momentarily causing the voltage to rise on an input such that the MC thinks it is "ON"?

Cheers,

Jack

[Boeing 747 Flyer]

Alright, I have spent the day today dismantling everything and separating out the cards.

I have connected JUST the USBExpansion card to my PC, and in SIOC Monitor I can see huge flickering across all cards despite no master cards being attached whatsoever. Although I do appreciate that they (USBExpansion cards) aren't meant to be used by themselves.

After plugging all four master cards in (with NO inputs/outputs attached, nor any power supplies), all flickering stops... For the first time stability across all four master cards, even after commanding an "ALL ON" - though yet again bare in mind absolutely nothing is connected to the master cards.

Any ideas where I should go from this stage?

[iwik]

Jack,
I would connect up your Leds and 7 segment displays you may be using. Then do an ALL ON. Max noise will be generated
then.
Just to recap what was actually happening. You commanded a ALL ON in SIOC Monitor and the inputs start flickering, did
this then cause the the inputs to FSX to change also. So if you looked at your panel in FSX were the switches changing.
One thing I did notice with my setup in the early days was that if I didn't connect up 5v to the master card then
switch inputs would go crazy. At that time I was running 7 segment displays as well.
Les

[Boeing 747 Flyer]

Hi Les,

Thanks for your response. I will try and connect the LEDs and 7-segments one-by-one and see when the flickering starts.

In terms of do they flicker in FSX - Yes, they do. I am using Nico's Lekseecon program to interface to the LDS 767, and there is certainly a huge amount of flickering of switches all across the overhead panel so it's definitely an active problem.

[Boeing 747 Flyer]

Right, after doing some work today, I've gotten to the stage where I have gotten the flickering problem replicated with just two master cards connected. The important thing is that they are connected in such a way that I can now easily plug/unplug whatever I want.

I can again confirm that it is indeed master card number 2 that is causing the problems... I'll see if I can isolate the exact cable that is causing the problems. I'll also be getting a more powerful power supply soon to test that theory too.

[Boeing 747 Flyer]

Even after unplugging all outputs such that there are ONLY inputs connected, I still get the flickering with the 5V power supplies connected after an "ALL ON" has been commanded.

Tomorrow I'll drive out to my local "proper" electronics store and have a root around. Like you say Les, perhaps I should be looking for a PC PSU. Any particular rating recommendations?

[iwik]

Jack,
Does this flickering occur with just one card or does it only do it with two cards if. If only with min of two cards try
another combination of two cards just in case one m/c is faulty. It may need more than one card connected to cause
a problem. Just loading of two cards could bring about the problem. One standard PC P/S should handle two cards fine.
If you have not connected any LEDS/7 segment displays then flickering should not happen as there is virtually no
load on the p/s.
I would definitely try a PC p/s as many problems can be caused thru poor power supplys.
Let us know how you go.
Les