AVR Freaks

Yeah I tried those .. didn't work. Also checked connectivity between arduino - display. Tried 3.3V then 5V for display. I tried the adafruit examples and a couple examples from youtubers. From 1 to 10 how possible is it that this display could be bad? As far as I know these LCDs are pretty durable. I did order it from China though and it could have had quite a ride during shipment.

God did I really brick it? I followed videos like this: https://www.youtube.com/watch?v=...

He connects all logic pins directly to Arduino ports and the display's VCC to Arduino 3.3V . His display works fine... This makes no sense.

I also believed that when a pin is configured as input, it has high impedance and that's why I thought it would be ok to drive a 3.3V device with 5V on its logic pins. How wrong am I?

I guess that's why I end up in this forum every time.. should have known better

It was on warranty when it arrived but I never checked if it worked - I bought it for future projects. Buying from ebay only comes with the risk of waiting 1 month and ending up with a broken item but you never lose your money through ebay warranty - this is not a sponsored comment. So to me - still worth buying 4 screens in stead of 1 in hopes that >=1 will work.

So here is what I tried on my new display and still had no result:

This Arduino sketch

// LCD5110_Graph_Demo
// Copyright (C)2015 Rinky-Dink Electronics, Henning Karlsen. All right reserved
// web: http://www.RinkyDinkElectronics.com/
//
// This program is a demo of most of the functions
// in the library.
//
// This program requires a Nokia 5110 LCD module.
//
// It is assumed that the LCD module is connected to
// the following pins using a levelshifter to get the
// correct voltage to the module.
//      SCK  - Pin 13
//      MOSI - Pin 11
//      DC   - Pin 5
//      RST  - Pin 6
//      CS   - Pin 7
//
#include <LCD5110_Graph.h>

LCD5110 myGLCD(13,11,5,6,7);

extern uint8_t SmallFont[];
extern uint8_t arduino_logo[];
extern unsigned char TinyFont[];
extern uint8_t The_End[];
extern uint8_t pacman1[];
extern uint8_t pacman2[];
extern uint8_t pacman3[];
extern uint8_t pill[];

float y;
uint8_t* bm;
int pacy;

void setup()
{
  myGLCD.InitLCD();
  myGLCD.setFont(SmallFont);
  randomSeed(analogRead(7));
}

void loop()
{
  myGLCD.setContrast(70);

  myGLCD.clrScr();
  myGLCD.drawBitmap(0, 0, arduino_logo, 84, 48);
  myGLCD.update();

  delay(2000);

  myGLCD.clrScr();
  myGLCD.print("LCD5110_Graph", CENTER, 0);
  myGLCD.print("DEMO", CENTER, 20);
  myGLCD.drawRect(28, 18, 56, 28);
  for (int i=0; i<6; i++)
  {
    myGLCD.drawLine(57, 18+(i*2), 83-(i*3), 18+(i*2));
    myGLCD.drawLine((i*3), 28-(i*2), 28, 28-(i*2));
  }
  myGLCD.setFont(TinyFont);
  myGLCD.print("(C)2015 by", CENTER, 36);
  myGLCD.print("Henning Karlsen", CENTER, 42);
  myGLCD.update();

  delay(5000);

  myGLCD.clrScr();
  for (int i=0; i<48; i+=2)
  {
    myGLCD.drawLine(0, i, 83, 47-i);
    myGLCD.update();
  }
  for (int i=83; i>=0; i-=2)
  {
    myGLCD.drawLine(i, 0, 83-i, 47);
    myGLCD.update();
  }

  delay(2000);

  myGLCD.clrScr();
  myGLCD.drawRect(0, 0, 83, 47);
  for (int i=0; i<48; i+=4)
  {
    myGLCD.drawLine(0, i, i*1.75, 47);
    myGLCD.update();
  }
  for (int i=0; i<48; i+=4)
  {
    myGLCD.drawLine(83, 47-i, 83-(i*1.75), 0);
    myGLCD.update();
  }

  delay(2000);

  myGLCD.clrScr();
  for (int i=0; i<8; i++)
  {
    myGLCD.drawRoundRect(i*3, i*3, 83-(i*3), 47-(i*3));
    myGLCD.update();
  }

  delay(2000);

  myGLCD.clrScr();
  for (int i=0; i<17; i++)
  {
    myGLCD.drawCircle(41, 23, i*3);
    myGLCD.update();
  }

  delay(2000);

  myGLCD.clrScr();
  myGLCD.drawRect(0, 0, 83, 47);
  myGLCD.drawLine(0, 23, 84, 23);
  myGLCD.drawLine(41, 0, 41, 47);
  for (int c=0; c<4; c++)
  {
    for (int i=0; i<84; i++)
    {
      y=i*0.017453292519943295769236907684886;
      myGLCD.invPixel(i, (sin(y*6)*20)+23);
      myGLCD.update();
      delay(20);
    }
  }

  delay(2000);

  for (int pc=0; pc<3; pc++)
  {
    pacy=random(0, 28);

    for (int i=-20; i<84; i++)
    {
      myGLCD.clrScr();
      for (int p=4; p>((i+20)/20); p--)
        myGLCD.drawBitmap(p*20-8, pacy+7, pill, 5, 5);
      switch(((i+20)/3) % 4)
      {
        case 0: bm=pacman1;
                break;
        case 1: bm=pacman2;
                break;
        case 2: bm=pacman3;
                break;
        case 3: bm=pacman2;
                break;
      }
      myGLCD.drawBitmap(i, pacy, bm, 20, 20);
      myGLCD.update();
      delay(25);
    }
  }

  for (int i=0; i<25; i++)
  {
    myGLCD.clrScr();
    myGLCD.drawBitmap(0, i-24, The_End, 84, 24);
    myGLCD.update();
    delay(100);
  }
  myGLCD.setFont(SmallFont);
  myGLCD.print("Runtime (ms):", CENTER, 32);
  myGLCD.printNumI(millis(), CENTER, 40);
  myGLCD.update();
  for (int i=0; i<5; i++)
  {
    myGLCD.invert(true);
    delay(1000);
    myGLCD.invert(false);
    delay(1000);
  }
}

I checked my connections several times and also made sure that the pins on my clone nano were correctly named by blinking an LED on each one of them.

The result should have been identical to what this video shows right at the start --> https://www.youtube.com/watch?v=...

a) An Arduino logo displays for 2 sec

b) A library logo displays for 5 sec

c) A line animation shows up

Still nothing shows up on my screen - even after trying several settings for contrast. I also used a multi-meter on continuity and on resistance mode to check on my connections - all seemed normal, still no results.

I used the connections recommenced by Sparkfun with limiting resistors:

My Arduino uses an old boot-loader... could this be a problem?

I used my Hantek osciloscope to take some captures of the pin signals from power up. I know there is not much definition at 1sec/division but the signals seem to be correct from afar. Cold you take a look at them as well?

I cannot tell you how many times I have checked my wiring already. I am seeing dreams of that Red 5110 pinout. Also I did check sketch pin configuration.

I am also confident the wiring is correct because of that 1sec/division scope I did - everything seems normal. The RST rises and stays put MOSI seems to be giving data at the appropriate times etc etc...

Yes, I was also worried about this big rising time on my signals so what I did next was use these commands:

  CLKPR = (1 << CLKPCE);

  CLKPR = 1 << CLKPS3);

to presale my FCPU by a factor of 1/256. I checked that the CPU was prescaled using a simple blink sketch - it was. Still no luck.

Could you check where the pcb's pins are routed to on the screens interface?

I am so looking forward to seeing your scoped signals

Yess! And the harder it was to get it working the greater the eureka moment - I definitely had a good moment. Thanks for helping me get there :)

Yeah that sure is good advice, sleeping on a problem is the best way to help solving it sometimes. Maybe dreams help in some way - who knows