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XC888 - LCD power up sequence....

Sam Manning

In certain situations, my LCD will not power up.

I am using an Infineon XC-888 micro driving a 16x4 LCD in 4-bit mode.

The LCD is based on the ST7066U IC, the c-code is based on the DAvE structure.

LCD Datasheet:
www.sitronix.com.tw/.../ST7066Uv22.pdf

I have been playing around with software delays and timing, but in certain situations, the LCD will power up and others not.

Here are my observations so far:

When I re-program the device, there are no problems, it is always when power is removed... and then re-applied.
I have previously tried inserting a really long SW delay to give the lcd time to power up, but that doesn't work.

The "line LCD_init4bit();" is in 2 places in the code below, when the one inside the "while(1){...}" loop is removed, it will not power up when power is applied.
When the one outside the while loop is removed/commented out, and the one inside enabled, it works.
This also leads me to believe that there is nothing wrong with the function itself, but like I previously said, I have already tried long SW delays to give the LCD time to power up.

I am not sure about reset vectors or the compiler, but any suggestions would be muchly appreciated.

Thanks


void main(void)
{
  // USER CODE BEGIN (MAIN_Main,2)

  // USER CODE END

  MAIN_vInit();

  // USER CODE BEGIN (MAIN_Main,3)

  //INT_vDisableAll();

  setOutputBits(PASS_LED + FAIL_LED);

  delay(1000);

  resetOutputBits(FAIL_LED);

  delay(100);

  LCD_init4bit();

  //INT_vEnableAll();

  // USER CODE END

  while(1)
  {

  // USER CODE BEGIN (MAIN_Main,4)

  LCD_init4bit();

  resetOutputBits(PASS_LED);

  delay(10000);

  LCD_instruction4bit(CLEAR_DISPLAY);
  delay(1);

  LCD_sendstring4bit("Hello World");
  delay(1);

  setOutputBits(PASS_LED);
  delay(1);

  // USER CODE END

  }

} //  End of function main