Hi, all...
I have an arduino duemilanove 328p and nokia 5110 interface as follow backgroud go dark make can't see text or display in direct angle(in oblique angle can see it)
Arduino GND -> Nokia5110 GND
Arduino 3v3 -> Nokia5110 Light
Arduino 3v3 -> Nokia5110 Vcc
Arduino 3 -> R10K -> Nokia5110 SCLK
Arduino 4 -> R10K -> Nokia5110 SDIN
Arduino 5 -> R10K -> Nokia5110 DC
Arduino 6 -> R10K or R1K -> Nokia5110 SCE (R10K or R1K they are the same result)
Arduino 7 -> R10K -> Nokia5110 RST.
I use the first code in this link for test.
http://ianlangelectronic.webeden.co.uk/#/lcd-module-0/4569058582
please help...
Thanks...
I try to use Capacitor 22uF 16V astride Nokia Light and Gnd now display look clear but i'm not sure if any better suggestion please help...
Read what it says under the words "Nokia 5110". Then check whatever data you have for this particular device.
There should be a contrast control setting in that programme but I can't see it. I think a more useful programme is here
http://blog.stuartlewis.com/2011/02/12/scrolling-text-with-an-arduino-and-nokia-5110-screen/
but I don't think it is the entire solution. I believe the main problem is power
Run it with VCC on the 3.3v pin and get rid of all the resistors. Connect everything directly except the backlight, which should be left disconnected for the moment. The blue backlight is useless and you may find you are better off not using it at all. I have never had a problem with direct connected backlights and I have heard that limiting resistors are built into the display, but a 560 or 1k resistor is usually used.
I think that you ultimately be better off forsaking Lang and using the Philips PCD8544 library, but note that you may have to edit it for the pin call and again adjust the contrast.
Hi, Nick
Thanks a lot for your answer and advices. If you mean the word below Nokia 5110 on the top of display board is "3v-5v" then I try 4 cases from your advice.
- Get rid of all resistor, use 3v3 and no use GND then
- Add resistor(1K or 120) to LIGHT then
- Try code from the link your suggestion the background not clear but still can see text then
- I changed "LcdWrite(LCD_CMD, 0xBf); // Set LCD Vop (Contrast). //B1" to 0xB5 background become clear
So i feel happy for your help! Thanks again....
Please resize your pictures, they are bigger than the resolution on my 27" monitor! 
Resize so they are < 1000 pixels on the longest side.
// Per.