FT800 Backlight

[James81]

Der All

I am facing the problem that the Backlight Output is active for a short time period when I change from FT800 Powerdown to Active. I am doing the follwing.

Code: Select all

//Action before FT 800 is in normal Active mode, display is displayed and every thing works fine  

FT800_Core_PowerMode(_FT800_PWR_MODE_PWRDOWN);
HAL_GPIO_WritePin(FT800_PD_GPIO,FT800_PD_PIN,GPIO_PIN_RESET);       //sets the PD_Pin low

//Now the FT800 is in powerdown mode. All is off and all RAM content is celared 

HAL_GPIO_WritePin(FT800_PD_GPIO,FT800_PD_PIN,GPIO_PIN_SET);         //pull PD_Pin high to indicated wakeup  
HAL_Delay(20);                                                                               //Delay to let FT800 be stable acc. Datasheet 

InitVTFTStack(0);                           //reinit of Vtft since all RAM Data is lost. This is your generated function from Vtft  
DrawScreen(&MainScreen);              //Draw the Main screen  

Whit this code I have follwoing behavour:
In the beginnign the backlight is on, the wehn Powerdown, backlight is off. On Wakeup the backlight is on for ca. 1s and off again when Drawscreen is called. After Drawscreen backlight is on.

Any Ideas?

[James81]

Nobody???

[Aleksandar.Mitrovic]

Hi,

Can you tell me whether your backlight fade in and out on the second turning on or just turn on?

Best regards,
Aleksandar

[James81]

Hi
It just turns on with white screen.

[Aleksandar.Mitrovic]

Hi,

Can you please attach me your project and describe me which hardware are you using?

I would like to try that on my hardware and in debug mode.

Best regards,
Aleksandar

[James81]

Hi I can sent it to support E-Mail adress, as uros indicated by helping me with another problem.

But can you tell me What happends the Backlight output after or during the function FT800_Init() is processed? This Function is taken form your library.

[Aleksandar.Mitrovic]

Hi,

Can you tell me for which compiler and MCU exactly?
I will take a look at the source code.

Send it to the same address like the previous one if its not a problem.

Best regards,
Aleksandar

[James81]

Hello

I can see the problem that yxou dont have the dedicated hardware.
I will try to build up the misbehaviour on the EasyMxPro for STM32 and your ConnectEve board.
But this takes a bit of time, I will post as soon as I get something.

Thanks

[Aleksandar.Mitrovic]

Hi James,

The example and the library for other compilers are working.
We have tested this many times. Including the ATXmega boards.

Best regards,
Aleksandar

[James81]

Hello

I found the Backlight truns on when FT800_Init(); is processed. What setting is this function doing to the PWM Output.

The Help gives me following description.

Description Init FT800 controller with default library settings of internal modules :

GPIO,
PWM,
SOUND,
AUDIO,
TOUCH (sampling + coord transformation),
INTERRUPT and
DISPLAY.
Check _FT800_CONFIG module constants for default config values.


Where can I find this _FT800_CONFIG Module?

Regards

Jörn

[dibor]

Hi.
Try to check in the xxx_driver.c file, if you generate code for MikroC compiler.

Regards.

[James81]

Hi

Yes there is

Code: Select all

const TFT800PWM VTFT_FT800_CONFIG_PWM =
{
  200,            // Freq = PWM frequency - 14 bits
  0,             // Duty = PWM duty cycle, 0 to 128 is the range
};

But this is not used by FT800_Init(); What I need to know is, what does the FT800_Init(); Function do to the PWM output of the backlight. I can see that the PWM output is activated since the backlight lights on. Therefore I want to modify the Init Function that no PWM output is generated.

Regards

[Aleksandar.Mitrovic]

Dear James,

We can not share with you FT800 library unfortunately.

I will assist you on this problem and offer you some solution.
Which hardware are you using with the FT800?

Can you attach me the small project which represent this behavior?

Best regards,
Aleksandar

[James81]

Hi Aleksandar

I am using a dedicated Hardware, but I am trying to demonsterate the behaviour on EasyMxPro for STM32 and ConnectEve board.
Meanwhile can you check what happends to the Backlight PWM Output of FT800 during FT800_Init();

Regards

[Aleksandar.Mitrovic]

Hi James,

I can see that You are setting the RST pin low then high in your project to initialize this display again.

Can you try to add this lines after the FT800_Init:

Code: Select all

FT800_Display_SetConfig(&VTFT_FT800_CONFIG_DISPLAY);
FT800_GPIO_SetConfig(&VTFT_FT800_CONFIG_GPIO);

And then draw the screen.

Best regards,
Aleksandar