BBB LCD Interface


I have Beaglebone Black and We have followed the procedures as mentioned in the website to boot the OS we are not facing any problem with booting up its working well.

In order to use the LCD we have disabled HDMI also .
The LCD which we are using is a 5.7" LCD with 16bpp RGB interface mode.

We have made some changes to the existing device tree given for “cape-bone-LCD3-00A0.dts”.

We are able to set all the required parameters to LCD interface like Pixel Clock, HSync, and VSync we are getting proper output on this pin, only issues is that the Data Enable (DE) signal its not coming properly, so we are not very sure the OS is actually transferring the data to LCD are not,
So can I know the reason for this and also solution for this.
Thank you.

I don’t know the answer, either. I wonder if you have solved this problem.
In fact, I am a newbie to BBB and embedded system. I want to make BBB to display but I don’t know how.

Check the LCD DE pin is muxed for any other purpose. And i have questions of

  1. What you getting in dmesg?

  2. Is the LCD dtb0 is loaded?

My previous problem was solved…
thank you…

But now im facing new problem like I have a LCD with clock frequency 33MHz when I tried to interface by making changes in the “cape-bone-LCD3-00A0.dts” and “BB-BONE-LCD4-00A0.dts” the clock is not getting set to 33MHz.
Can I know the reason for this??

Also I tried to edit the “BB-BONE-LCD7-00A2.dts” but when I tried to echo it to slots its giving an error that “no such file or directory found”. I read some where that the version 00A2 is supported for latest angstrom version and should boot from sd card im doing the same but still not succeded so can I get any sujjestion???

Hi chaitra,

Are you interfacing any custom lcd or cape?

Dear chitra,

I am a novice with begal bone black. I want to connect LCD with the BBB, but as the P8 pins are already connected with HDMI, how to connect LCD.

I want to connect 20x4 LCD.

Please help.

by a 20x4 lcd, you mean a 20x4 character lcd, correct? generally
these are a simple serial or 8/4 bit parallel interface. got a data
sheet to share (preferably a link)?

Dear sir,

Thank you for your support.

Below is the link for of the LCD supplier. We are currently using 20 X
2 LCD. yes it means 20 characteres in 2 lines. But as the P8 line is
already accupied to HDMI it is continuosly giving us High signal and
we are not able to connect our LCD with the module.

Please find the attached datasheet also.

LCD _ODM 20216S Data sheet.pdf (113 KB)

Hi Vignesh,

Sorry for poking in between Chaitra’s thread. I am also trying to interface a custom Touchscreen.
I am using 3.5” TFT-LCD with Touch Panel Module. I have modified the BB-BONE-LCD-LCD4-01-00-A0.dts file and compiled it to create the .dtbo.
I am successfully able to disable the HDMI cape and could manually load the modified BB-BONE-LCD-LCD4-01-00 using the command
echo BB-BONE-LCD-LCD4-01-00 > $SLOTS where $SLOTS is configured to slot8. But still not able to get any output on the screen.
Can you tell me what I need to do to make this lcd-tft panel to work?