Green LED on - Red LED not so much (resolved)

[drlucas]

Hi there,

I purchased an assembled usb dongle and just got my lynx express (separate order) and excited to test things out....anyways on a Mac and on a Win7 machine, both with the usb drivers installed all I get is the green LED when i connect the device to a pc (or mac). the port shows up under device manager when i connect the usb cable but the red LED isn't on.

any thoughts on what might be wrong, or where I can take my troubleshooting?
thanx!
Ryan

[rrowan]

Do you know if the dongle pic was programmed? What firmware was used (DMX/Pixelnet)?

Have you tried sending data to the LE?

Rick R.

[tbone321]

The RED LED may be installed backwards.

[drlucas]

will attached the front and back side of the board....looks like the +ve was clipped on the back of the board, so I think the LED was installed respecting the polarity.

Zach's post said the dongles were assembled and tested, so assume they were programmed with dmx firmware (not 100% sure).
---
Sale/Trade / FOR SALE V2 DMX Dongles ::SOLD::
« on: January 15, 2013,  »
I've got two V2 DMX Dongles fully assembled and tested boards.  No cords or enclosure included.  PM With offers or questions.
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also, look at the faint scratch on the one trace on the back of the board...not sure that would cause this issue or not.

final thoughts....i tried to send data using xlights....xlights is setup as dmx for network type, com3 last channel 512. the LE is connected over a wireless not just dmx over ethernet cable (will take wireless out of the mix)...i've reset the LE to show 001 on the display and have it as terminated. i click output to lights and xlights says testing 8 channels....nothing happening there. i can run the test cycle on the LE and it works as expected (i suppose - i'm new, but it blinks lights). 

[drlucas]

an image of back

[drlucas]

image of front

[drlucas]

tested direct from usb dongle to LE and no difference. tried to reseat the three chips and make sure all pins were in.. no difference.

SO...if someone could look at the traces on the back of my pic and see if there is anything wrong from first glance (i'm not really good at electronics yet, and my volt/amp/combo unit needs a new 9v battery so if there are places to check on the pcb let me know and I can do some of that testing too).

worst case.... the next step is post something up on the sale board and wait to see if someone else is selling something....

any guidance is appreciated (as always!)
thanks!
ryan

[JonB256]

In your last picture, if you zoom in on the Green, then the Red LEDs, their Anode/Cathode construction look "reversed" to me.

So I opened up one of my dongles and compared. Again, I think the Red LED is in backwards.

[drlucas]

i looked at this link - You are not allowed to view links. Register or Login and it looks to me that the +ve has the thin metal vs the -ve side that has the wider piece within the led (sorry for lack of technical term).

lets say though that they are reversed....(i'm still not there yet)  would that shut the board down, or just not light the LED?

[tbone321]

The Red LED is just a power LED and I'm not sure how the Data LED (green) could light if it was not getting power.  It is possible that the dongle was foashed for Pixelnet and if so, then the LE would not respond to it.  I would also reduce as many variables as possible.  Eliminate the wireless and make sure that the LE's jumpers are is set up to work with wired.  If you have a Picket 2 or 3, reflash the PIC to the latest DMX firmware and if not, I would suggest that you get one.  In the mean time, you could always send the dongle to someone who has a functioning system to test it for you.  It can get difficult to debug when you don't have anything that you know for a fact works. 

[rm357]

With the DMX firmware, the red led is usually visible. With the pixelnet firmware, you need to turn out the lights and look at it in a dark room... It also helps to turn all channels on...

[drlucas]

thanks...the last two posts give me hope

i'm going to get a pic programmer .... it's on the list of things i need for the hobby and i'm up in Toronto and not aware of anyone else who is local who can help me troubleshoot.

i don't mind shipping it out to the US to verify, but i think i'll get the programmer, reflash first and take it from there....any good links to someone who sells them (i haven't tried google yet)

thanks again.
ryan

[zach stoltenberg]

Doc,

Can't seem to get a reply out by e-mail, keep getting an auto response that the address is no longer active on the server.  The pic is flashed to straight DMX, not pixelnet.  I was wary of using proprietary pixel protocols so I never really got into it.  I replaced a bad red LED before it was shipped, I may have gotten it in backwards (red polarity is reversed).  If you have a green light you should have DMX going.  Without seeing your settings on the computer I'm not sure where there's a software problem.  The dongle was one of a few that was used a few seasons back but it was tested and used successfully before being shipped.  Give me a call when you get a chance and I'll try to help you troubleshoot.  Have you tried it with any other DMX devices?  Where the LE assembled or a kit?  Wondering if you have a problem with the LE or with the cabling possibly.

Zach

[Dennis Cherry]

If I remember correctly does not the DLL file used for the USB Dongle need to be a specific DLL?

[rm357]

You have to install the ftdi driver before plugging in the dongle. Windows doesn't always get the right one and it does not work well with the Microsoft drivers.

In my earlier post, I meant the green data led, not the power one...


The Vixen software needs the proper dll for DMX or pixelnet. Most of the other software does not.

For testing, I would use the lynx deck or xlights. Those programs are both easy to setup and use - without having to define or setup a lot of stuff...