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Altera_Forum's avatar
Altera_Forum
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16 years ago

DE2 LCD BackLight

I have recently gotten the LCD to display text and numbers like I want, but I CANNOT get the LCD backlight to come on. There is a pin called PIN-K2 that is for the backlight and I have it set to VCC, why will it not come on? Do some of the DE2 boards not have this option? Also I'm using Quartus 2 to code the VDL and compile it.

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Look at your LCD , on the right of it, there are pads of baclight, if nothing is soldered there you don't have BL...

    I am not sure, but DE2 from University Program, doesn't have BL at all.

    Commercial version maybe has it.

    You can unsolder your lcd and solder one with backlight.

    Backlighted one are higher too. It is lcd based on chip HD44780.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    If this can be of any help I cn tell you that I run a smal project on the DE2 board and found the backlight signal completely unuseful.

    At the end the text was readable and I did not care about it anymore.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    --- Quote Start ---

    Look at your LCD , on the right of it, there are pads of baclight

    --- Quote End ---

    Well, according to the schematic and user manual, the backlight - if present at all - is connected through the 16 pin connection rather than the dedicated backlight pins.

    The LCD module type referenced in the DE2 System CD datashet has a white LED backlight. But as said, there may be different versions. A visual inspection should clarify whats assembled to your DE2 board.