DLPLCRC900DEVM: Maximum refresh rate of DLP670S with DLPLCRC900DEVM

Hello Nick,

Welcome to the E2E forum. Thank you for your business!

Can you provide more information? Specifically, which version of the GUI are you using? It should read 5.0.0 or 5.0.1. What version does the firmware report? It should read either 6.0.0 or 6.0.1.

Is the "Video Running" box checked when running at 30 Hz in either Video Mode or Video Pattern Mode?

Best,

Maxine

Hi Maxine,

Thanks for getting back so quickly.

GUI is 5.1.0 and Firmware is 6.1.0.

At 2716x1600 30Hz in Video Mode, Video Running is checked and the picture updates correctly. In Video Pattern Mode, Video Running is not checked and the picture does not update.

At 2560x1600 60Hz Video Running is checked in both Video and Video Pattern Mode. The picture does update.

At 60Hz I have the Exposure set to about 16500us and at 30Hz 33000us, though I have tried with shorter exposures to see if that is the problem. I have also tried both Dual Pixel and Single Pixel modes.

I see the same problem if I select 2560x1600 30Hz in Windows.

Unfortunately we really do require to operate at the native resolution. 30Hz will likely not be a problem so long as Video Pattern Mode works.

Thanks,

Nick

Video Pattern Mode settings

Status at 2560 x 1600 60Hz

Status at 2716 x 1600 30Hz

Hello Nick,

Which video system are you using to drive your output signal? Some video cards have limitations that could cause the behavior you're currently seeing.

Furthermore, while Video Mode is compatible with both 60 Hz and 30 Hz for receiving/displaying, we do not believe that Video Pattern Mode is compatible with 30 Hz. We are consulting with our software team to confirm this and will get back to you by early next week.

Best,

Maxine

Hi Maxine,

I am driving the DisplayPort from Windows. It is detected as a PnP monitor (see the last couple of images from my previous past). Looking in the registry I can see the following EDID data.

Preferred Detailed Timing:

Pixel Clock : 265 Mhz

Horizontal Active : 2560 pixels
Horizontal Blanking : 160 pixels
Horizontal Sync Offset : 48 pixels
Horizontal Sync Pulse Width : 32 pixels
Horizontal Border : 0 pixels
Horizontal Size : 2560 mm

Vertical Active : 1600 lines
Vertical Blanking : 24 lines
Vertical Sync Offset : 3 lines
Vertical Sync Pulse Width : 6 lines
Vertical Border : 0 lines
Vertical Size : 1600 mm

Input Type : Digital Separate
Interlaced : False
VerticalPolarity : False
HorizontalPolarity : True

Detailed Timing #2:

Pixel Clock : 165 Mhz

Horizontal Active : 2716 pixels
Horizontal Blanking : 260 pixels
Horizontal Sync Offset : 8 pixels
Horizontal Sync Pulse Width : 32 pixels
Horizontal Border : 0 pixels
Horizontal Size : 2716 mm

Vertical Active : 1600 lines
Vertical Blanking : 248 lines
Vertical Sync Offset : 2 lines
Vertical Sync Pulse Width : 7 lines
Vertical Border : 0 lines
Vertical Size : 1600 mm

Input Type : Digital Separate
Interlaced : False
VerticalPolarity : False
HorizontalPolarity : False

Is there any chance of new timing information which would allow operating at 2716x1600 at 60Hz or any frequency supported by Video Pattern Mode?

I look forward to your update,

Nick

Hello Nick,

Thank you for the information. We were able to reproduce what you're seeing using Video Pattern Mode at 30 Hz and are investigating on our end. We will get back to you within the next few days with updates.

Best,

Maxine

Hello Maxine,

I want to confirm, because this is quite a long thread, that I need Video Pattern mode to work at the native resolution of 2716x1600. I don't have a requirement for a specific refresh rate, just one which works!

Thanks for your help,

Nick

Hello Nick,

Yes, we are looking into Video Pattern Mode at 2716x1600.

Best,

Maxine

Hello Nick,

At the current moment, the DLPC900 controller does not support the native resolution, 2716x1600, in Video Pattern Mode. However, Video Mode does support the native resolution and will run as intended.

Both Video Mode and Video Pattern Mode are supported at 30 Hz and 60 Hz at the standard resolution.

Best,

Maxine

Hello Maxine,

My colleague has been in touch with other contacts in TI to chase whether a change can be made to allow this mode. Video mode is not an option for us due to the extra processing which reduces the image quality.

Nick

Hello Nick,

We are actively exploring the scope of the effort that enabling the full native resolution at 30 Hz.  Let's continue the discussion in the email thread with your colleague that you referenced if you are amenable.

Fizix