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Support Forum » first and third line on lcd help

April 04, 2012
by wi6791lly
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been messing with this kit for about 2 days just trying to fix this LCD issue. I am pretty sure I have everything wired up right to the LCD and still get these lines. I have no idea what is wrong either anything to test would be greatly appreciated. using a power supply I made in electronics class for my input voltage and at a steady 9v the whole time. kit is NK003USB

some pics 1 2 3

April 04, 2012
by hevans
(NerdKits Staff)

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Hi wi6791lly,

For the most part your wiring looks ok. The programming switch looks to be installed on the wrong side of the chip, but that should only be a problem when you start trying to program the chip. Were you ever able to see the initial congratulations message on your LCD, or did this problem start when you started trying to program your chip?

Humberto

April 04, 2012
by wi6791lly
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never got to see the welcome message. I had started trying to program but couldn't get it hooked up to win 7 64 bit PC. but would love to get it running before worrying about the PC issue.

the only thing I have done wrong (that I know of, aside from the switch) is had the input voltage hooked up wrong at first, I was inputting into the outside on the 7805 and was getting the entire LCD screen black, changed that and now have 2 lines instead of 4.

happy to provide any other angles you want

April 04, 2012
by dvdsnyd
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Hi,

It looks to me like the LCD is wired up correctly. It is getting power, so that is good. The thing that glares out to me isn't so much the LCD wiring, but the placement of your programming switch. You have it on the opposite side of where it normally is. The switch goes into rows 24, 25, and 26 on the lCD side. Some of the LCD wires connect through the switch too.

Honestly, I have had this same issue where the LCD gives the same output a few times. The first time I had a wire misplaced and was lucky enough to find it. One time I accidentally managed to erase the program on the MCU so the LCD was getting exactly what MCU was giving it...nothing. So in that case I finally reprogrammed the MCU and it worked. The last time I had something similar I couldn't find the issue and ended up tearing everything out of my breadboard and starting from scratch...twice. It is really the only way that you can cover all your bases. It is really difficult to look at each connection and verify it.

Have you gotten the first message to come up? Where in the guide are you?

David

April 04, 2012
by wi6791lly
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just tried totally removing the programming switch and turning on and off and the same lines occur. also removed the wire from ground to that point as well

April 04, 2012
by wi6791lly
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the only issue I can spot but phone will not focus in close enough to show it, is some light bits of soldering on pins 4 and 6 and then some with a little more but still appears to be a good connection on 1 and 2

April 04, 2012
by dvdsnyd
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So you are just trying to do the first welcome message? Have you done anything with the programming switch, other than put it on and take it off just now?

Your best bet may be to just start from scratch...It kinda stinks, but it works I must admit.

Have you tried starting over?

David

April 04, 2012
by wi6791lly
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I had tried messing with the switch in the wrong place but otherwise not. I'll try a total restart then and be back after that

April 04, 2012
by dvdsnyd
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wi6791lly Humberto

Could the accidental mis-wiring erase the program on the chip? I explained a similar incident earlier. Where I reprogrammed the chip and it worked. I don't know what I managed to do to do it though. I know I was fumbling with the wires from the battery.

David

April 04, 2012
by wi6791lly
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just rewired the LCD and got the same 2 lines up. and if i should try rewiring gonna need help getting it going on win 7 64 bit

April 04, 2012
by 6ofhalfdozen
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Dunno if it matters or not, but the crystal looks like it is sitting really HIGH off the breadboard. Might want to check and see how well seated it is in the breadboard, I had a few issues with a "wiggly" crystal.(it didn't give my LCD issues, but played havoc with other stuff) I have trimmed the legs on my crystals back so that they sit really close to the breadboard surface. I don't know if that is an issue, but figured I would mention it as a maybe..

April 04, 2012
by wi6791lly
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trimmed them off some and now sits pretty close to the board and same issue

April 04, 2012
by dvdsnyd
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What issues are you having on the programming side? I am running Win 7 64 and have no problems.

David

April 04, 2012
by wi6791lly
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first a question does the circuit need to be on when hooking it up.to the computer?

then if not I couldn't get the com port as the circuit was showing up as unknown device or something in the device manager window

April 04, 2012
by dvdsnyd
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Were you able to install the USB cable drivers?

David

April 04, 2012
by wi6791lly
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yep installed them without issue

April 05, 2012
by hevans
(NerdKits Staff)

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Hi wi6791lly,

If the USB Drivers were installed correctly then you really should see the PL2303 device in the COM port. Are you still seeing unknown device?

Humberto

April 06, 2012
by dvdsnyd
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Which drivers did you install? For Win 7 64- install the Vista drivers. Seems obvious...but I didn't the first time I tried installing them.

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