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Topic: Dead serial enabled 20x4 Sparkfun LCD (Read 3464 times) previous topic - next topic

Avantime

This is the LCD:
http://www.sparkfun.com/products/9568

Without warning it stopped responding to serial commands, the backlight is off, and only shows two rows of black rectangles, on row 1 and row 3.

What should I do?

liudr

I don't know. Did it indicate it's got flu by sneezing? You should post what you did to the poor thing, starting with code, what you are doing with the code, then attach a few hi-res pics. Without the above, I can only recommend CPR. :)

James C4S

It sounds like the microcontroller (that talks serial and sends commands to the screen's controller) is the problem.  It probably turns the backlight on / off and it initializes the screen.

Rows of black squares tend to indicate the screen's controller hasn't been initialized yet.
Capacitor Expert By Day, Enginerd by night.  ||  Personal Blog: www.baldengineer.com  || Electronics Tutorials for Beginners:  www.addohms.com

liudr

Without the details, I can only think what James mentioned, plus, maybe you didn't give the serial backpack enough time to initialize before you start commanding it to do stuff. If the MCU is fried, then you can still use the display as a parallel one.

mrprecise

I had one of those LCD's some time back. The onboard PIC can become scrambled/brain dead by leaving the serial line connected when uploading a sketch to the Arduino. Searching the forum, I wasn't the only person this happened to! All the suggested fixes did not work for me, and I was not into learning how to re-program the chip, even though the code is available.

Solution: Get a regular LCD, and get the Serial LCD117 board from,  http://shop.moderndevice.com/. The PIC chip, in multiple baud rates, is programmed/sold by:

http://www.phanderson.com/

Peter H. Anderson (KZ3K), Associate Professor, Department of Electrical & Computer Engineering
Morgan State University, Baltimore, MD. e-mail pha@phanderson.com
Hometown - Springfield, VT. Same as the Simpsons.

Never had another problem with my LCD's. They are bullet-proof! As an added bonus, the Serial LCD117 board makes available (4) ttl outputs which Anderson has included in his code, which can be used for led's, freeing up Arduino pins.
John

Staedtler

#5
Feb 01, 2011, 03:35 am Last Edit: Feb 01, 2011, 03:39 am by Staedtler Reason: 1
Lets start the random assumption game.

I think is the Catalytic Converter. :)

Quote
only shows two rows of black rectangles, on row 1 and row 3.

That means that the LCD display is OK.

...but more than that, please...

... what liudr said.

--------------------------------------
Eight bytes walk into a bar. The bartender asks, 'Can I get you anything?'
- 'Yeah', reply the bytes

mrprecise

True, the LCD is not fried.

If your up to the task, learning how to re-program the mcu might be fun. I just did not want to invest the time required, and got another LCD. The built in serial mcu is simpler, and takes less space than an add-on board, but has it's downside.   

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