Hey

so i wrote the programm again...and it is working better now...but i changed the contrast in the NOKIA_5110.h to a hex value of 0xCD it was 0xC8 by default. Problem now is still that the contrast is too weak with just one line...but if i raise the contrast value i get black vertical lines all over the display...

maybe its just the cheap chinese display...for 3$ it is good enough i think...just want to learn a bit to use the nucleo and some text prints on the lcd.

wanna see the code of the latest version?

Thanks for your support guys. =)

I dont have that display type myself so cant test, but please post the code so we can have a look. Did you check the powersupply voltage on the display pins.

Edit: any progress with the display? Make sure the metal frame is pressed firmly against the PCB. Is has springs to lock it in place. Perhaps one of the display's connection pads which connects to the PCB with a sort of conductive rubber (zebrastrips) is not making good contact. This is especially important for the VLCD out pin which should connect to a capacitor on the PCB. VLCD out is the output of the on-chip LCD voltage generator. The contrast will be unstable when the Cap is missing.

i am using the same library like i was told too.

my code i am using is

#include "mbed.h"
#include "string.h"
#include "time.h"

DigitalIn mybutton(USER_BUTTON);
DigitalOut myled(LED1);
Timer timer;

int main()
{
    int timer_value = 0;
    bool running=0;  
    
    LcdPins myPins;
    myPins.sce  = D8;
    myPins.rst  = D7;
    myPins.dc   = D10;
    myPins.mosi = D11;      //SPI_MOSI;
    myPins.miso = NC;
    myPins.sclk = D13;      //SPI_SCK;
    NokiaLcd myLcd( myPins );
    
    
    vPcStringPrint("Setting up LCD");
    myLcd.InitLcd();        // LCD init
    vPcStringPrint("LCD set up complete");
    vPcStringPrint("Entering While Loop");
    myLcd.SetXY(0,2);    
    myLcd.DrawString("Entering WhileLoop");
    wait(2);
    myled = 0;
        while(1) 
        {
            if(mybutton == 0)  // Button is pressed     
            { 
                if(running== 0)
                {   
                    myLcd.ClearLcdMem();
                    running = 1;    
                    timer.start();
                }

            }
    
            if (mybutton == 1 && running == 1)
            {
                timer.stop();                           // Zeit stoppen
                running = 0;                            // Byte auf 0 setzen
                timer_value = timer.read_ms();          // Zeit speichern
                vPcTimePrint(timer_value);              // PC-Ausgabe
                char value[timer_value];                // Char value erstellen
                sprintf(value, "%d", timer_value);
                myLcd.SetXY(0,1);                       // LCD lokalisieren
                myLcd.DrawString("Time was ");          // Text Ausgabe
                myLcd.SetXY(0,2);                       // LCD lokalisieren
                myLcd.DrawString(value);                // Wert auf LCD schreiben
                myLcd.DrawString(" ms");                // Text Ausgabe
                timer_value = 0;                        // Zeit auf 0 setzen
                timer.reset();                          // Uhr reseten
            }   
        }   
}

the time.h is just a library written by me with all declarations of functions or prototypes...dont worry about that.

the display looks perfect in this programm...but just because i am plotting more than 1 line to the lcd...if it is just 1 line its not that good.

/media/uploads/Shadowrap411/img_4851.jpg

The code above probably wont compile. The #include "NOKIA_5110.h" is missing (unless you have included that in time.h).

There is also something wrong with

char value[timer_value];  

You should not declare that array with a variable size. It must be a constant that is large enough to make sure that the integer produced by sprintf fits. Try something like

char value[32];  

In case you still get contrast problems make sure the powersupply is OK. It should be 3V3 for the display.The Nokia 5110 display uses a Philips PCD8544 LCD controller. That device is rated for 2V7..3V3 powersupply Ignore what is says on the display printed circuit board about 3V..5V. The vertical lines could be the result of overvoltage breakdown on the LCD controller. The controller has a voltage multiplier to generate the LCD driver voltage (6V..8V5) from the powersupply voltage. When the powersupply is too high the LCD voltage will also be too high and things could break.

In case none of that helps the display may just be broken.

BTW I found a Nokia 5110 cellphone + charger at a fleamarket last week (cost me 75 Eurocents). Ripped out the display and keyboard PCB, hooked up some wires to mbed and it works fine..