NHD-0216KZW-AG5 - serial interface - initialization

bw

• January 23, 2018 10:06

Hello
I use mentioned above OLED 2x16 display with serial interface.
Everything is almost ok, but i cannot find initialization procedure for serial interface.
For now i tried with 8bit parallel initialization sequence, but sometimes my oled doesn't start. Is that timing problem or something else?

What is proper way of init this display in serial mode? This is not specified in datasheet.

0

• 

  Saurabh_B

  • January 30, 2018 15:46

  Hello,
  You can find an example on how to use the Serial OLED below:

  sbit SCL = P3^4;
  sbit SDOUT = P1^0;
  sbit SDIN = P1^1;
  sbit C_S = P3^3;
  
  void delay(unsigned int n)    //Delay subroutine
  {
  unsigned int i,j;
  for (i=0;i<n;i++)
      for (j=0;j<250;j++)
       {;}
  }
   
  
  void WriteCommand(unsigned char ins)
  {
  unsigned char i;
  C_S=0;
  SCL = 0;
  SDOUT = 0;  //RS = 0 (Command)
  SCL = 1; //RS registered
  SCL = 0; 
  SDOUT = 0;  //RW = 0
  SCL = 1; //RW registered
  SCL = 0;
  
  for (i=0x80;i;i>>=1)
  {
  if((ins&0x80)==0x80)
  SDOUT = 1;
  else
  SDOUT = 0;
  ins=(ins<<1);
  SCL = 0;
  SCL = 1;
  SCL = 0;
  }
  
      C_S=1; 
  }
  
  void WriteDataInit()
  {
  
  C_S=0;
  SCL = 0;
  SDOUT = 1; //RS = 1 (Data)
  SCL = 0; //RS registered
  SCL = 1;
  SCL = 0;
  SDOUT = 0;  //RW = 0
  SCL = 1; //RS registered
  SCL = 0;
  
  }
  void WriteData(unsigned char dat)
  {
  unsigned char i;
  for (i=0x80;i;i>>=1)
  {
  if((dat&0x80)==0x80)
  SDOUT = 1;
  else
  SDOUT = 0;
  dat=(dat<<1);
  SCL = 0;
  SCL = 1;
  SCL = 0;
  }
  
  }
  
  void init()
  {
  WriteCommand(0x38);//function set
  delay(30);
  WriteCommand(0x06);//entry mode set
  delay(30);
  WriteCommand(0x02);//return home
  delay(30);
  WriteCommand(0x01);//clear display
  delay(30);
  WriteCommand(0x0c);//display on
  delay(30);
  WriteCommand(0x80);//line 1 character 1
  delay(30);
  }
  
  void main()
  {
  char i=0x21, j;
  
  
  
  init();
  
  while(1)
  { 
  C_S = 1;
  WriteCommand(0x80);  //Line 1 
  
  WriteDataInit();
  //WriteDataInit() must only be executed once before starting to write data
  //if WriteDataInit() is executed between writes, the display will recognize the two bits as data bits and not RS/RW bits. 
  for(j=0; j<20; j++)
  {
  WriteData(i++);
  delay(10);
  }
  
  C_S = 1;   
  //Pulling C_S High means write data is completed
  //if next instruction to the display is data, must use WriteDataInit() first
  //if write command is executed without pulling C_S high, it will recognize the following instruction on the bus as data regardless
  WriteCommand(0xC0);  //Line 2
  
  WriteDataInit();
  for(j=0; j<20; j++)
  {
  WriteData(i++);
  delay(10);
  }
  
  C_S = 1;
  WriteCommand(0x94);  //Line 3
  
  WriteDataInit();
  for(j=0; j<20; j++)
  {
  WriteData(i++);
  delay(10);
  }
  
  
  C_S = 1;
  WriteCommand(0xD4);  //Line 4
  
  WriteDataInit();
  for(j=0; j<20; j++)
  {
  WriteData(i++);
  delay(10);
  }
  
  }
  }

  0

Please sign in to leave a comment.