DLP4500: Cannot continuously display 2 pattern sequence patterns in single 24bit video stream data in the pattern sequence mode

Part Number: DLP4500

Dear all,

I am testing with DLP4500EVM and I encounter cannot continuously display 2 pattern sequence patterns in single 24bit video stream data in the pattern sequence mode.

Below is the pattern sequence settings I set in the DLP4500 Light crafter GUI.

I am continuously transfer video data to the DLP4500EVM with Vsync signal frame rate around 59.81Hz and the pixel clock is 73MHz. Below is the DLP4500EVM feedback signal.

Blue signal is Vsync signal. Pink signal is DLP4500EVM TRIG_out_1 signal. I am getting delay of 1 frame DMD video output everytime.

In the user guide manual, it suppose to have 1 frame delay of DMD video output for the first frame of video input only that show in the diagram below.

Is my pattern sequence settings got problem?

Thank you.

Best regards,


  • Pang,

    It sounds like you are saying you have every other frame of your video feed shows empty data, is that correct? Are you using a constant video stream, or are you starting and stopping the data? Are you sending VSYNCs with no data attached?


    Philippe Dollo

  • Dear Philippe Dollo,

    I am using constant video streaming so the video data is not empty. Besides, the video data is always send together with the VSYNC.

    Previously I am using the 7bit for the pattern sequence settings. Now I tried to set the pattern settings to 4bit shown below. The projection signal looks ok.

    Blue signal is VSYNC and pink signal is TRIG_OUT_1 from DLP4500EVM. I am using same streaming program do to the test.

    Best regrads,


  • But I need to use 7bit pattern sequence settings. What cause the 7bit pattern sequence settings cannot work as 4bit pattern sequence settings?

  • Weng Yeon Pang, 

    I am not sure if you have already tried the following check - please use the validate sequence feature of the GUI to re-check that the sequence you want to want to display is supported by the system or not.

    Let us know your findings. 



  • Dear Mayank,

    Thanks for your reply.

    Everytime I change the pattern sequence settings, I will use the validate sequence button of the GUI to validate the sequence settings and the results are passed.

    I have try the below video data settings but the behavior still the same. Delay of 1 frame everytime then only the EVM starts the pattern sequence.

    Pixel Clock = 146 MHz


    Resolution = 912

    Front Porch = 56

    Sync Pulse = 64

    Back Porch = 10


    Resolution = 1140

    Front Porch = 17

    Sync Pulse = 10

    Back porch = 3

    Horizonal Sync Frequency = 140.12 kHz

    Vertical Sync Frequency = 119.76 Hz

    Horizontal Period = 1042 Pixels

    Vertical Period = 1170 Lines

    Can you share the settings or setup that you able to function the EVM to display two 7bit pattern sequences continuously in pattern sequence mode with parallel RGB interface as pattern source?

    Thank you.

    Best regrads,

    Weng Yeong

  • Weng Yeong,

    Thanks for the feedback. The team needs some time before getting a response back to you. Expect something within the next week.

    Best Regards,


  • Dear Philippe,

    Looking forward to your feedback. Thanks a lot.

    Best regards,

    Weng Yeong

  • Weng Yeong,

    No problem. Thanks ahead for your patience. Will keep you posted.