LCD2041 Displays Blank on Power ON

Nitin Garg · Post by **Nitin Garg** » Fri Feb 23, 2007 4:28 am

Hi All,

I am using LCD2041 Rev2.0 display. It was working fine till yesterday when suddenly it stopped responding to I2C commands. I power cycled it and it started displaying Blanks (Earlier "Matrix Orbital" logo used to display). I tried RS232 communication but its not responding. It responds to RS232 only when J0 jumper is installed (reset to factory defaults).

After going through the manual, I tried reseting it to factory defaults by closing J0. But when J0 is closed it displays garbage.

Any clue what is going on?

Regards,
Nitin

Raquel · Post by **Raquel** » Fri Feb 23, 2007 10:32 am

Hello Nitin,

Thanks for your post.

First off, I can see that you probably meant LCD2041 instead of VFD2041. It sounds that somehow maybe the module has been configured differently (unintentionally). With the manual override jump on, keep the mode on RS232, use uProject to communicate with the module.

Can you please send me a picture of the back of the module?

Nitin Garg · Post by **Nitin Garg** » Mon Feb 26, 2007 5:25 am

Thanks Raquel,

The main problem was that the contrast was set to 255 due to which blanks were appearing. Secondly the unit was programmed to invalid I2C address and baud rate was invalid.

I am now able to communicate to unit through I2C and serial.

However the text now appears tp be garbage in between. The scrolls are incorrect and lines end with special characters.

Kindly suggest how should I get a correct display.

Raquel · Post by **Raquel** » Mon Feb 26, 2007 9:56 am

Hello Nitin,

It sounds as if there is timing issue that is why you see the garbage characters. Can you please post a picture of the back of your display?

Thanks,

Nitin Garg · Post by **Nitin Garg** » Mon Feb 26, 2007 11:57 pm

Hi Raquel,

The I2C bus is configured for 100Mhz.
Can the fonts and Graphics in LCD be corrupted?

Regards,
Nitin

Raquel · Post by **Raquel** » Tue Feb 27, 2007 12:02 pm

Hi Nitin,

You mentioned before that this module was working fine. I have not seen a case where the built in fonts are corrupted. Do you use any characters other than alphanumeric (A-Z, a-z, 0-9), say an arrow sign or something?

Also, when you first power the display up, does it show its normal start up screen? Can you turn the backlight on and off using I2C?