NHD-C12865AR-FSW-GBW display is not able to display any data but commands are working

Comments

4 comments

  • Engineering Support
    Community moderator

    Hi,

    Thank you for waiting on us. Could you please confirm that you are providing the correct power to the display?

    Your command and data functions have different parameters types. 

    void Display_Write_cmd(unsigned char cmd)
    void Display_Write_Data(unsigned char* data, uint16_t size) 

    For your data function could you try the following instead: 

    void Display_Write_Data(unsigned char data, uint16_t size) 
    1
  • Engineering Support
    Community moderator

    Hi,

    The Vout is determine with a combination of the software and the booster circuit. I wonder if the change in the parameters in the data function caused this voltage change. Could you please revert back your code to what you originally had and measure Vout again? The Vout pin is the supply for the LCD contrast since you are measuring 10-11V it means that the contrast is high and might be difficult to see if any graphics are being displayed. The typical contrast would be 9.5V.

    1
  • jeet

    Engineering-Support

    Thank you so much for your response. 

     

    Okay, I will try as per your suggestion. yes, I am providing 3.3V to display and receiving 10-11V at Vout.

    what is ideal voltage at Vout?

    My initialization command sends below mentioned values:

    0xE2 for internal reset

    0xA0 for ADC normal operation

    0xA2 to set bias 1/9

    0xC0

    0x2C for power control

    0x2E for power control

    0x2F

    0x2F for booster

    0x00 for booster 

    0x77 for resistor ratio

    0x64 for contrast

    0xAC for static OFF

    0xAF to turn display ON

    0xA5 to make all points On

     

    EDIT: I was trying to change my initialization code but now I found out that I am not getting 10-11V at Vout but only 2.5V. Does that mean ST7565 is damaged? or I configured ST7565 wrong?

     

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  • jeet

    Thank you so much for your response. 

    Okay. I will plan according to your suggestion.

    0

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