how to shut down LCD before the standby Mode?

[Linda]

Posted on June 18, 2015 at 01:49

My Dear,

In order to save battery, we want to shut down the LCD before the standby Mode.We use Stm32f429 i Disco.

How to do that?

Thanks

[Linda]

Posted on June 18, 2015 at 02:33

I already try to write all pin connect to LCD to 0, like:

GPIO_WriteBit(GPIOA, GPIO_Pin_3, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_4, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_5, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_6, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_7, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_8, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_11, Bit_RESET);

GPIO_WriteBit(GPIOA, GPIO_Pin_12, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_0, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_1, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_8, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_9, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_10, Bit_RESET);

GPIO_WriteBit(GPIOB, GPIO_Pin_11, Bit_RESET);

GPIO_WriteBit(GPIOC, GPIO_Pin_2, Bit_RESET);

GPIO_WriteBit(GPIOC, GPIO_Pin_6, Bit_RESET);

GPIO_WriteBit(GPIOC, GPIO_Pin_7, Bit_RESET);

GPIO_WriteBit(GPIOC, GPIO_Pin_10, Bit_RESET);

But this way doesn't work.

[Tesla DeLorean]

Posted on June 18, 2015 at 02:55

Haven't you basically asked this same question before?

You have a couple of options, but you'll need to review the schematic and think about it.

You could remove the R47..R50 resistors to LEDK, and gate the ground with a FET. That's the backlight.

You could remove the 3V supply to it and the other non-CPU circuits, JP3 might be a good point to separate things.