3.3v issue, very dim display

[GoogleCodeExporter]

Hi

First many thanks for the great library!

I am using this with a dog081 lcd and arduino, all works fine when powering it 
with 5v but when i switch over to 3.3v (I have measured and assured my voltage 
reaching the screen) I get a very dim display. I initiate the display in the 3v 
vcc mode (according to the written wiki) and even set the contrast to max 
allowed but still the display is dim, so you almost see nothing. I use a 
reflective screen, no backlight.

Would this be my unit beeing wrong or something with the code? I tried to 
intrpet the boosting you do but not really sure i got it..

Thanks in advance

Original issue reported on code.google.com by krs...@gmail.com on 7 Mar 2011 at 12:16

[GoogleCodeExporter]

Hi,
did you add the 2 capacitors that are needed for 3.3V operation?

Have a look at the schematic in the datasheet 

http://www.lcd-module.de/eng/pdf/doma/dog-me.pdf

On page 4 you have two different schematics for 3.3V and 5V operation 
(SPI-Mode), with 2 extra capacitors for 3.3V operation

Eberhard

Original comment by e.fa...@wayoda.org on 10 Mar 2011 at 7:29

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[GoogleCodeExporter]

Hi

Yes initially I had missed that out to be honest in the datasheet but
I realised that i needed to add the capacitors some hours after I put
the initial the post up. The issue is however that even with the
capacitors added the display is dim, even at the highest contrast
level of 0x3f (63) the display stays pretty dim. I have ordered an
additional dog lcd 3x16 so I should try this out also first and see if
there will be any change or something wrong with my setup sio I will
put a follow up if it is better, otherwise the library works perfekt!

Many thanks for the quick response!

Regards Krste

Original comment by krs...@gmail.com on 10 Mar 2011 at 8:45

[GoogleCodeExporter]

I'm not sure if my I made the initialization steps for the display clear enough 
for 3.3V operation.

Have you seen this section in the wiki?
http://code.google.com/p/doglcd/wiki/Library#Initialize_the_display

You must to use the begin() method from example 3: 

whateverYouVariableNameIs.begin(DOG_LCD_M162,0x30,DOG_LCD_VCC_3V3);

(Remember to use the matching constant for your type of display)

Original comment by e.fa...@wayoda.org on 10 Mar 2011 at 12:57

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Original comment by e.fa...@wayoda.org on 26 Sep 2011 at 9:11

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