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Support Forum » LCD row 1 and 3 light up with no data

September 30, 2010
by elektron
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I have checked and rechecked my wiring several times, tried different wires and different holes (same node) on the breadboard, but cannot get the "Congratulations...." message. Is it possible that I got an empty MCU? Any help will be greatly appreciated.

September 30, 2010
by Ralphxyz
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Welcome, elektron, always that possibility, but doubtful. Chances are it is a wiring problem can you post some pictures of your setup.

You can remove everything from your breadboard and start over or move on to the temperature sensor project to make sure something is "loaded" on your MCU.

What do you mean that row 1 and three light up? Pictures will help a lot.

If you move the programing switch to the up (left towards mcu) position do you get two black bars? If so then you probable are wired correctly. If you do not get two black bars the simplest thing to do is to start over.

When you start over, completely strip everything off your breadboard start from scratch.

Ralph

September 30, 2010
by mongo
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Black bars also means the MCU program mode is active.

October 02, 2010
by chlucfeng
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I am having similar difficulty. I did receive the initial Congratulations message with the scrolling text, then had to disconnect a few wires to put away and head to class. Now, I am trying to install the initialload.c file and have it display. I did the COM check thing, and am using COM4. I made that change to the makefile. Starting with power on, and programming pin on (up), The program loads, and I get the thank you prompt. Next, I turn the program switch off (down), and still see the row 1 and row 3 black bars. I then try power off, then back on, and still get two black bars. I want to complete this before the temperature sensor.

October 02, 2010
by hevans
(NerdKits Staff)

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Hi chlucfeng,

The two back bars can be a sign that your MCU is in programmming mode, but it could also mean your LCD is just not getting any data. To make absolutely sure that your MCU is not in programming mode just remove the programming switch from the breadboard. Reset power to the chip, and see if your initialload message comes up. If it doesn't double check all the LCD wires, and make sure you didn't accidentally knock one loose when it was put away. Let us know what you find.

Humberto

October 02, 2010
by chlucfeng
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Pulled all long wires. Rewiring currently. I had some shorter than I like, so I am making a longer set to allow more flexability between the screen and breadboard. will reply again soon.

October 02, 2010
by chlucfeng
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The new program has displayed correctly. Attempting tochange programs.

October 02, 2010
by chlucfeng
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It's a beautiful thing! My new message appears after I turn of the display, and turn it back on. Is there a way to store multiple messages and call them by number, and have the screen refresh between them? I shall finish this tutorial, and watch more video. My answer may be in front of my nose, but if you could point me in the right direction, I will jump to that tutorial.

Thanks, Chuck

January 09, 2011
by SirHobbes3
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I am experiencing some of the same problems, i rewired after the lcd worked properly, but now only the first and third rows show. I have checked all wires and i know for sure that it's not in programming mode. I am still troubleshooting but to no effect.

January 09, 2011
by SirHobbes3
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In more details.... I first hooked everything up, then i tested everything and got the first message. Then i hooked the kit up to my computer [COM4] and changed everything the right way, then i did the makefile thing, and that worked as well. I rewired to allow more flexibility between the breadboard and the LCD screen. So i hooked up the battery again and i only got the 1st and 3rd rows. I checked all connections like in the guide, but to no avail. so i have been trying to figure out the problem. The kit is FOR SURE not in programming mode.

January 09, 2011
by hevans
(NerdKits Staff)

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Hi SirHobbes3,

The first and third row of black squares means that the LCD is getting no data from the MCU, so it could mean that it is in programming mode, the LCD isn't wired right, or that the MCU isn't running at all from some reason.

Are you able to flash a new program on to the MCU consistently? This will tell us if your chip is running correctly.

If you can post some good close up pictures of your setup we would be glad to double check your wiring to see if you accidentally missed something.

Humberto

January 10, 2011
by SirHobbes3
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After i rewired everything, i was able to consistently send data to the MCU. I've already checked that the chip isn't in programming mode.

January 11, 2011
by hevans
(NerdKits Staff)

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Hi SirHobbes3,

If you can consistently get a new program on the MCU it indicates your chip is working just fine. I suspect the most likely cause of your issue is a loose or misplaced wire to the LCD. If you post some pictures of your setup, we would be glad to take a look.

The other possibility is that your LCD is not working for some reason. Can you think of any reason why your LCD might have been damaged? Any short circuits, sparks, or very hot components?

Humberto

January 12, 2011
by SirHobbes3
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I'll try to get some pics of my setup. I do think that i might have a loose wire; some of my wires aren't as long as wanted, but it works, somewhat.

I MIGHT have short circuted something when i rewired the 1st time, i think i might've put a wire on the +5 volt rail instead of the -5 volt rail, or something might not have been at ground.

January 12, 2011
by elektron
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I experienced this problem when I first got my nerd kit. I checked my wiring at least 10 times before posting my help message on this thread. A few people were nice enough to reply to help me and suggested I recheck my wiring, so I gave it another shot. To my extreme embarrassment, I found 1 wire misplaced in the breadboard. I was too ashamed to reply and report what was found, but now I'm over it. Ahhh,the follies of being human. A belated thanks to those who helped.

January 14, 2011
by SirHobbes3
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!!!!!!!!!!!!!

I have rewired and i guess the problem must have been a loose or misplaced wire, after i rewired the message displays perfectly!

"Congratulations!

Your NerdKit is alive!"

January 14, 2011
by mongo
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It's ALIVE!!! Igor threw the switch and the creation lives!

Welcome to the world of troubleshooting. Some times, the littlest things can give you the biggest problems.

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