LiquidCrystal Library garbled or no text

Forum 2005-2010 (read only) Hardware Interfacing
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I have been searching the interwebs and this forum for a little over 2 hours now and I am just plain stumped. I wired and uploaded the Example HelloWorld sketch for the LiquidCrystal library. It was working fine displayed to the screen. I uploaded it a few more times each saying different things to get a feel for it. Great awesome, working... I then rewired it and reuploaded... Stopped working. I know what you are thinking, check the wires, check the wires and check the contrast pot. Well did that, did that and did that. I uploaded a few modified sketches and nothing. Went back to the HelloWorld example and there it is working on the display. I then tried to go back to another example, write to the display using the serial monitor. And all I get is garbled text. Thing about it is the characters are not random, when I type 'a' I get some set 'b' will give me something and it's always the same crap characters that are displayed.

I am now back at the example LCD HelloWorld and it doesn't even display anything (NOTE: I commented out the stuff that incremented the time, my loop() method is empty) With that code in place it would display garbled text on the first line and seem to update every second, I am assuming because that is when the second ticker is suppose to update.
LCD is from sparkfun

Data sheet for my LCD

Arduino Board
Modern Devices RBBB with atmega 328, uploading with their USB BUB.

Running Arduino v0018 on Window 7.

EDIT: Well I went away from it for about 15 minutes and came back wired everything directly into the lcd with no breadboard between the lcd and the arduino. BTW forgot to mention I have female headers on both the arduino and lcd. I am still trying to figure out why it went wonkers, I am going to rewire it to the bread board and see if it still works. Also checked the pins it was assigning the writing to.

EDIT2: Rewired back to the breadboard and everything seems to be fine. Again still wondering what was going on. My best guess is that the memory got corrupted (On LCD) and time out from power seemed to fix that. Might have even been in arduino itself, possible a timing issue with the library or the chip.

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Are we supposed to figure out how your modified sketches might have affected the LCD memory without the benefit of knowing their contents?

Don

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lol. By modified I mean changing the string that it was displaying (No crazy characters... EX "lcd test", "noobs" and a few others. Other than that they were stock. I started to flail after it went wonkers on me.

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i think he ment please trow the code up here

and check the data lines btw
and/or check the cables...

its not the first time a datapin is missing here on the forum :stuck_out_tongue:

greetz SaSaa

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I changed the pins that it was outputting on, seemed to fix a few problems. I might have damaged the other pins in my last project. Doesn't seem to be happening anymore, BUT: I have noticed that the IDE can get into a weird state that causes it to not save the changes you worked on and you keep making changes and keep uploading but nothing changes. I think this is what I saw. A simple restart of the program and cold boot of the board seem to fix that. Well and you might need to go back through your code and make sure it didn't decide to clobber any of your changes. It seemed to keep some and kill others.