STM32F769 Discovery kit makes high pitched noise

[Kristof Mulier]

Posted on November 19, 2017 at 12:55

Dear STMicro,

I bought an STM32F769 Discovery kit but cannot use it for a very frustrating reason. When I switch it on, it generates a high pitched noise driving me crazy. The noise is not loud, but the high tone (high pitch) is extremely annoying.

I think it is related to the display.

Can you please help?

#use-stm32f769-discovery-board #stm32f769i-disco

[john doe]

Posted on November 19, 2017 at 14:01

after your call to BSP_LCD_Init(); add this:

uint8_t lcd_brightness[] = {OTM8009A_CMD_WRDISBV, 0xFF};

 DSI_IO_WriteCmd(0, (uint8_t *)lcd_brightness);  // stop the whine

[Kristof Mulier]

Posted on November 19, 2017 at 17:56

Hi John Doe,

This is awesome! Thank you so much, it worked immediately.

How did you find this?

You seem to know a lot about how to drive displays. What library do you use for your graphics? I know there are a few commecial ones, like uGFX, Embedded Wizard, ... but I would like to use an open-source one.

[john doe]

Posted on November 19, 2017 at 18:44

I don't know anything about driving displays, I just have the same board with the same problem. I got the info from this thread:

https://community.st.com/0D50X00009XkfGQSAZ

I haven't played around with this board very much, so I haven't chosen a graphics library.