DLP4500 with 1280x800@120Hz in Video Mode

user4700800 said:

Hi, 

We have been trying DLP4500 with 1280x800@120Hz in Video Mode. (Firmware Version is 3.0)

But the projected screen is always updated slower than 60Hz and there are many frame drops,

whereas we have no problem with 1280x800@60Hz in Video Mode.

Are there any limitations to the frame data which can be output at 120Hz?

Can we get 1280x800@120Hz in Video Mode?

 

Our NVIDIA GPU display setting is customized exactly same as:

https://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/924/p/331370/1160989#1160989

and the pixel clock is below 150MHz which should be OK. 

Also, we have already checked the following but were not able to find the right way:

https://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/924/t/499863

https://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/924/t/331370

https://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/924/t/312672

We are using: WIndows 8.1 Pro. NVIDIA Geforce Titan X, HDMI->mini HDMI

Best regards, 

The LightCrafter 4500 EVM don't have fine tuned video display sequences for 120Hz operation; this is the reason why video appearing choppy; the end use of the EVM predominantly designed for pixel accurate mode of operation. 

Regards,

Sanjeev

Sanjeev

Thank you for your fast reply.

Could you clarify the pixel accurate mode of operation?

Do you mean 912x1140@120Hz in Video Mode is OK?

 

We thought 120Hz in Video Mode can work based on your following comment:

 

https://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/924/t/499863

"We have tested the EVM working for the 120Hz; all you need to do is to find out if you can configure the graphics card to generate the video timing;"

Regards,

>> Could you clarify the pixel accurate mode of operation?

Input gray-scale is linearly mapped to output light. There is no dithering or de-gamma adjustment. A typical requirement for non-video applications like machine vision or 3D scanning.

>> Do you mean 912x1140@120Hz in Video Mode is OK?

This is not okay as this exceeds the max pixel clock limit to display 912x1140 24-bit video @ 120Hz, this comes to ~154MHz pixel clock where as the controller supports upto 150MHz max.

>> We thought 120Hz in Video Mode can work based on your following comment.

We tested with still patterns using a test pattern generator, this would not show the lagging issue; you can perhaps use the 8-bit 120Hz 912x1140 pixel accurate grayscale display configuration.

Is your end application intended for regular video application? Something meant to be seen with human eyes? If it is then you can look these platforms http://www.ti.com/lsds/ti/dlp/video-and-data-display/getting-started.page

Regards,

Sanjeev

> Input gray-scale is linearly mapped to output light. There is no dithering or de-gamma adjustment. A typical requirement for non-video applications like machine vision or 3D scanning.

 

This does not seem Video Mode described in the DLPC350 Programmers Guide as follows:

 

"In video mode, the DLPC350 supports up to 1280x800 pixel resolution at 120 Hz through its 30-bit RGB or FPD-link interfaces. The DLPC350 processes the digital input image and converts the data into the appropriate format for the DLP4500 DMD. The DLPC350 processing functions include format conversion, chroma interpolation, and CSC. The DLPC350 also offers several image enhancement functions: degamma, primary color correction, chroma interpolation, scaling, and overlap color processing."

 

The LightCrafter 4500 EVM has a problem to use DLPC350 Video Mode at 120Hz? (i.e. Not supported/tested?)

We understand the EVM is not optimized for regular video-applications but would like to know if there are any workarounds.

 

Regards,

Hi,
We understand your point.

>> We understand the EVM is not optimized for regular video-applications but would like to know if there are any workarounds.
Let me check on this.

Regards,
Sanjeev

Hi,

Could you let us know the status on this issue? We would like to check if it can be fixed with a firmeware or something.

Regards,

Hi,

We are still evaluating with your request. Thanks for your patience.

Regards,

Sanjeev

Hi,

How is it going ? We hope you would have some progress on the evaluation...

Regards,

Hi,
I sent you a friend's request, can you please accept and provide us the details requested?
Regards,
SAnjeev

Hi,

Thank you for your friend request, Sanjeev.
But I'd accepted your friend's request a week ago, and you are already listed in my friends list in my profile page.

If I did some misunderstanding, let me know please.

Best regards,