Troubleshooting, part 1

plord · Joined: Dec 15, 2007 Posts: 21 Location: Charlotte, VT

Finally finished soldering and started testing this evening. I'm having enough issues that I stopped the tests partway through and came here to post Smile

First the good news: no smoke, continuity checks out, all ICs have power where they want power (and the right kind of it), and ground where they want ground. I made the same error as Loopcycle, thought my pattern switches were bit high when closed but they are bit high when open. Ooops, but no labels on my panel so not too damaging. Once I figured that out, manual load works fine and all switches and LEDs for the pattern behave correctly.

First problem: my Klee runs backwards. Clock LED blinks, but with bit 1 set it steps from 16 down instead of the right way. This backwards going behavior persists in 16x1, 8x2, and manual step mode.

Second problem, maybe related to first: In 8x2 mode, with Invert B on, step 9 pattern switch on, this happens: steps 1-8 light up in reverse order 8-1 until all are on, then turn off in reverse order 8-1 until all are off, and steps 9-16 step sequentially backwards from 16-9.

I have gate bus problems a-plenty. Let's save those for another post.

Third problem that seems strangely related to the first two. In the Bus 1 Load Switch test, with stage 5 set to bus 1, instead of stepping from 1-4, mine steps backwards from 16-6, skips 5-4-3-2, lights 1, goes to 16. Inverted and off by one. Hmmmmm.

Thanks for any help.

sduck · Posted: Wed Dec 10, 2008 7:35 am Post subject:

Everything sounds fine except for the backwards counting thing. Get that sorted out, and I think everything else will become non-issues. Scott will probably have an idea about that.

Scott Stites · Posted: Wed Dec 10, 2008 8:09 am Post subject:

Yep - lemme think about it for a bit (at work right now), but I'd say things are working, except they're about as backwards as they possibly could be. Not only are the bits running backwards, Register A is Register B and Register B is Register A.

More in a bit.....

Scott Stites · Posted: Wed Dec 10, 2008 8:42 am Post subject:

OK, just concentrating on what the LEDs are doing here - we should check the pot voltages and gate bus, too, but worry about that later.

I'm assuming your pattern loads as you expect, it just steps the wrong direction. That means your pattern switch signals are going where they should be going. Good.

Invert B is working (though backwards). Good.

The pattern is clocking. Good.

Things are going backwards. Not-so-good, but kinda cool...but, let's get it running forward. Very Happy

Sounds to me like you've got two plugs wired or plugged in backwards, and they're connected to the wrong jacks on the digital board.

Digital Board J8 connects the first eight LEDs. Digital Board J9 connects the second 8 LEDs.

If at all possible (if the connector keys let you) do this:

Unplug the plugs from J8 and J9.

Take the plug that was inserted into J8, turn it around and plug it into J9.

Take the plug that was inserted into J9, turn it around and plug it into J8. This will get your LEDs running in the right direction.

Don't worry about this reversing - even if I'm wrong, it's not going to hurt anything - those are all common signals, there's nothing to reverse.

Check the attached diagrams to see what I'm talkin' 'bout here.

Next, we'll make sure the voltages are tracking the LEDs and check out what's going on with the gate bus.

Lemme know what you find.

Take care,
Scott

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plord · Joined: Dec 15, 2007 Posts: 21 Location: Charlotte, VT

Thanks Scott, I'll try that out when I get home this evening.

I am suddenly having a terrifying suspicion that I screwed up the whole "back of the panel goes upside down and backwards" thing, possibly in more than one place. Which would be um, sub-optimal to maintaining my sanity.

All of you folks who made big honkin' panels with tons of space to work? U R SMRT.

Scott Stites · Posted: Wed Dec 10, 2008 9:11 am Post subject:

fluxmonkey · Joined: Jun 24, 2005 Posts: 708 Location: cleve

blue hell · Posted: Wed Dec 10, 2008 2:06 pm Post subject:

loopcycle · Joined: Nov 06, 2006 Posts: 101 Location: California

hm, i just read this as

plord · Joined: Dec 15, 2007 Posts: 21 Location: Charlotte, VT

Comprehensive wiring screwup: confirmed.

I tried swapping and reversing the plugs, the ones I have make this very very difficult. Tried going in with a tiny screwdriver and pressing the tabs that hold the wiring pins in the connector housing. That way lies madness Smile

SO, ordering new headers, unsoldering the mess I've made, and starting that part again. And looking on the bench to see what to torment myself with in the interim...probably the Quad Sequential Switch.

Thanks for the tips all, more reports when I'm back to the testing part.