Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: HeinrichG on February 22, 2017, 10:48:45 AM

Title: Using a LCD panel on LVDS connector
Post by: HeinrichG on February 22, 2017, 10:48:45 AM
Hello everyone,

at the moment I'm trying to connect an LCD panel to my BananaPRO (I think it's doesn't matter which SBC, A20 is alway A20 :) ).

The panel is an LG LM230WF5-TLF1, datasheet is here: click me (https://elektronik.mein-bmw-rudel.de/images/BananaPRO/LCD/LM230WF5-TLF1.pdf).

Then I've created a mapping between BPro and panel: click me (https://elektronik.mein-bmw-rudel.de/images/BananaPRO/LCD/lvds_0.1.xlsx), there are two sheets, pinning and mapping.

On the pinning are just a pin and symbol lists of both devices.
Mapping sheet "connects" lcd to BPro.

At the moment I'm not able to try this, because I'm waiting for pcb for LCD driver (power supply and backlight driver), but I can prepare all the stuff.

After that I added some lines to u-boot configuration (Bananapro_defconfig):


CONFIG_VIDEO_LCD_MODE="x:1920,y:1080,depth:24,pclk_khz:72000,le:48,ri:48,up:8,lo:8,hs:50,vs:10,sync:3,vmode:0"
CONFIG_VIDEO_LCD_PANEL_LVDS=y
CONFIG_VIDEO_LCD_POWER="PH7"
CONFIG_VIDEO_LCD_BL_EN="PH12"
CONFIG_VIDEO_LCD_BL_PWM="PB2"


recompile them, wrote them to sd-card. U-Boot version is 2016.11.

In my dts file is pwm configured as:


&pwm {
pinctrl-names = "default";
pinctrl-0 = <&pwm0_pins_a>, <&pwm1_pins_a>;
status = "okay";
};


Then I've created a pin definition for BL_EN and LCD_POWER (in &pio section):


bl_en_pin_bananapro: bl_en@0 {
allwinner,pins = "PH12";
allwinner,function = "gpio_out";
allwinner,drive = <SUN4I_PINCTRL_10_MA>;
allwinner,pull = <SUN4I_PINCTRL_PULL_DOWN>;
};

lcd_power_pin_bananapro: lcd_power@0 {
allwinner,pins = "PH7";
allwinner,function = "gpio_out";
allwinner,drive = <SUN4I_PINCTRL_10_MA>;
allwinner,pull = <SUN4I_PINCTRL_PULL_DOWN>;
};


and recompile dts file.

After reboot, I see this in dmesg:


[    0.319628] simple-framebuffer 7f817000.framebuffer: framebuffer at 0x7f817000, 0x7e9000 bytes, mapped to 0xf0900000
[    0.330308] simple-framebuffer 7f817000.framebuffer: format=x8r8g8b8, mode=1920x1080x32, linelength=7680
[    0.418036] simple-framebuffer 7f817000.framebuffer: fb0: simplefb registered!


It seems to be active.

It is enough or is something missing in my configuration?

Thanks and kind regards,
Heinrich

Title: Re: Using a LCD panel on LVDS connector
Post by: techsilvio on March 24, 2017, 05:37:39 PM
I'm tring same thing with 17" lcd panel , let me know if it work.