Display issue...

[shgshgshgshg]

Ok so I just got my pic programmed and the display is not showing me anything.
Other info, all three leds are on ( data, 5v, and 3.3v). Also when I press the select button the 16 channel led lights up. I have attempted to transmit the program from the configure utility and the first 2 leds light up and the rest flash very quickly.

My first thought was that I have some chips flipped the wrong way.

Thanks everyone, I'm sure it's a relatively simple problem, but I don't really know what to do from here.

[shgshgshgshg]

Sorry I accidentally posted twice. Also here is a pic of it attempting to be programmed...

[n1ist]

Check the 2700pF capacitor.  From the manual:

Take the 2700pf cap. Find the location for this and install it. On some of these capacitors, the outer yellow epoxy is coating the top of the leads. Make sure that the yellow portion is not stuck inside the hole on the board; the part of the lead that goes into the hole must be silver. It is OK if the cap is not flush with the board when you install it.

If that cap isn't soldered correctly, the display won't work.
/mike

[RJ]

Push and hold the reset button. Does the system act different?

Normally the cap issue that mike is pointing out leaves either two led digits working and not the middle or the middle and not the outer two.

RJ

[wftxlites]

The cap is easy to damage when soldering. Don't ask how I know. I suggest ordering spares if you plan on building more LE's. Another suggestion would be to leave the cap sitting a little higher on the top side of the board and be fast to solder it. Don't leave the iron on it too long, but make sure the joints are shiny.

Good luck,

Greg

[combustionmark]

Recheck the pic, I can't quite make out if it is in backwards or not. While you are at it, recheck the 485 chips as well, Heck recheck all them chips.. When you programed the pic, did you use a pickit 2 or 3? Did the checksum match with what was listed in the wiki? I have had problems programming the chip when using a laptop, Everythink checks out good, but the express refuses to work. Using a powered usb hub, or plugging in the express when programming seams to help.

Hope this helps.

[shgshgshgshg]

RJ - pushing and holding the reset button does not appear to change anything...
The 2700Pf is recessed pretty far away from the PCB. I wouldn't rule out the fact that it is blown due to heat though...

[shgshgshgshg]

Also I didn't do the pic programming myself I sent it off to be programmed, so I can't tell you of there were any issues there...

[RJ]

I do not remember a case where the cap would make all digits be out. I am worried your pic is not really programmed. Can you post some good clear closeups of both sides of the pcb for us to look at. Sometimes we can see stuff you missed.

RJ

[shgshgshgshg]

Ok here are a bunch or picture I took. My phone is the only camera I have at te moment.. :/

[shgshgshgshg]

Last one...

[shgshgshgshg]

For now I will be resecuring the chips that are on the board...

[tlh]

Hi, Stephen-
I am sorry to hear that you're running into problems. The PIC did seem to program correctly (with a Pickit 2; checksum was right and the PIC tested OK in one of my LEs). If it turns out that the PIC needs to be reprogrammed, just let me know and I'll send you a spare one of mine so the postage is on me. Regarding the pictures, the folks here are great for trouble shooting, so I am sure you'll get it working. You might try double checking to make sure that the PIC is firmly seated in the socket. It looks like it may be in at an angle. hope that helps. Best,
tlh/Terry


Sent from my iPhone using Tapatalk

[RJ]

Pic not program is just a guess I have nothing to go on. It is lifted in the socket so remove the pic and reinsert it carfully to check. Also tyr pushing the other buttons as if the buttons are in backwards they work backwards and holding them down will make the board work. We have had that before.

RJ

[shgshgshgshg]

ok, the only button that is doing something is the select button. When I press the select button down the channel 16 led lights up. The led goes off when the button is released.
One of the parts i did not order from mouser, it is the ST485BN but all the numbers on the part look the same.
And finally I had a lot of trouble getting the led display driver to align properly but I have reseated the chip.
Thanks for all the help guys, I'm confident we'll get this worked out soon.