LCD driver development and orientation

Vincent Chow

Other Parts Discussed in Thread: DM3730

Hi,

I got a request to use a special 600x800 4" LCD (manufactured by Sharp) to connect to the Sitara processor. The target OS will be one of the Linux distribution. However there are two things need to be solved:

1. How should the LCD driver development be started?

2. The target application wants to use the screen in landscape mode. I cannot find replacement of the same size / resolution in 800 x 600. Could it be done by driver level to transpose the image? (I know it may not be a good example, but Intel display chip on PC allows setting the screen orientation easily in Windows OS.)

Thanks a lot!

over 10 years ago

0 Biser Gatchev-XID over 10 years ago

TI__Guru**** 393215 points

Hi Vincent,

You should download the latest Sitara SDK. LCD drivers are included and you will just need to tune them for your LCD. Here is a wiki link for the Linux LCD Driver: http://processors.wiki.ti.com/index.php/Linux_Core_LCD_Controller_User_Guide
The AM335X LCD controller does not support hardware rotation. You will need to rotate the image by software before sending it to the frame buffer.

0 Vincent Chow over 10 years ago in reply to Biser Gatchev-XID

Prodigy 50 points

Hi Biser,

I came a cross a page describing the framebuffer console which supports screen rotation.
www.kernel.org/.../fbcon.txt

Can it work together with the AM335x LCD controller?

0 Biser Gatchev-XID over 10 years ago in reply to Vincent Chow

TI__Guru**** 393215 points

I'm not a SW expert, but from what I see this is a message console that runs on top of the framebuffer.

0 LeonardEllis over 10 years ago in reply to Biser Gatchev-XID

TI__Guru 71526 points

Hi Biser,

This post seems to indicate you can perform the rotation with a series of commands: e2e.ti.com/.../1068509 .

I have a user that has this same situation, the LCD has to be mounted 180-degrees rotation. I'm also wondering if there is some hardware setting on the LCD that could create the rotation, or if the driver has such a setting?

Any help would be greatly appreciated.

~Leonard

0 Biser Gatchev-XID over 10 years ago in reply to LeonardEllis

TI__Guru**** 393215 points

Hi Leonard,

The post you are referring to is about DM3730. The AM335X has a completely different LCD controller, that does not support hardware rotation.

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LCD driver development and orientation