Backligth arduino mega + mcufriend lcd

Hi, I am having some problems with my lcd mcufriend 3.95 480x320 ILI9488 or this is supposed.

After reading a lot the display and the touch panel works good modifying UTFT and Touch_AS libraries but I am trying to set the backlight or shut down the lcd and I can´t find the way.

Already tried some commands like 0x28, 0x10, 0xB9, 0xBA and some others after reading R61581 datasheet but only the display turn off, the backlight led still on… and the LCD pin is missed so I can´t do pwm.

I share the libraries because maybe can help someone else with the same lcd.

http://es.aliexpress.com/item/3-5-inch-TFT-LCD-screen-module-Mega-2560-R3-Mega2560-REV3-ATmega2560-16AU-Board-for/1843466129.html?adminSeq=202171486&shopNumber=1184212

At the UTFT.cpp file line 1235 you can see some of the code I tried calling the lcdOff() function.

If someone can help me… lots of thanks.

Pd: sorry for my poor english.

BOTONES_OK.ino (6.74 KB)

Touch_AS.zip (8.72 KB)

UTFT.zip (356 KB)

UTFT_Demo_480x320.ino (7.14 KB)

As far as I know, there is no pin to control the backlight on these Shields. The backlight is always on. And taking a lot of current.

Since you are probably using it on mains-powered supply, the power consumption is not important.

If you take the shield apart, you can find the backlight LEDs. Connect a transistor for switching the LEDs. Then use one of the spare pins at the bottom header to control the transistor.

Are you sure that your screen is 400x270 ? Are you sure that it has a R61581 controller ?

David.

The screen is 480x320 I think, because is the demo example I have run. The controler I think is R61581 or at least enough compatible because the example graphics demo run well.

I think I can put the transistor between the power pin and another pin to control it. But I have to initialize the display every reconnection.

Hoping for better solutions. By now is this or the lcd shield.

If you are happy to insert a transistor, just hack the shield. Glue the transistor to the back of the shield. Switch the backlight properly in software. You can send the controller to Sleep.

Voila, low current consumption. You wake up from Sleep with your original picture.

David.

The lcd uses 36 pin (unknown) connection and 6 more for ground power and reset. How can I find the correct pin to do that?

The lcd id returns a 0xEFEF