• TI Thinks Resolved

DLP4500: "Validate Sequence" slow (GUI/USB)

Prodigy 10 points

Replies: 5

Views: 148

Part Number: DLP4500

Dear all,

We are using LightCrafter 4500 for projecting different patterns. Initially we developed the application via GUI, now we are writing our own C++ code and controlling the module via USB.

We are always using two or three different sequences via "Pattern Sequence mode", but every time we send a sequence we need to validate it and lasts 1-2 seconds. Do we need to validate the sequences always, although they have been validated once and never again modified? Is there a shortcut to avoid it?

Looking for answers in the forum, I have seen some user that can plot signals (triggers, status) digitally so we can see the behavior of the module. Is there a hardware/software module that I could get to debug by observing different signals (or even reading I2C data)?

Is there any recommendation to control the module via I2C instead of using USB?

Thank you very much in advance for your help.

  • Hello Carlos,

    Are you using triggers for your application (either input or output)? And generally the USB commands and I2C commands are interchangeable and either can be used depending on your needs. We'll look into your question about the need for the validate command.

    Note there is an SDK that may help you get started too http://www.ti.com/tool/DLP-ALC-LIGHTCRAFTER-SDK



  • In reply to Kyle Rakos:


    Yes, we are using triggers. We have seen that  the validation time is related somehow with the complexity and the length of the sequence.

    We are using a similar source-code as the LightCrafter to manage the validation:



    The time between the start and the check ok (ready & status) takes 1-2 seconds. But also the GUI of the LightCrafter takes a while.




  • In reply to Aitor Matilla:

    Hi Aitor, 

    If you are using the same pattern sequence always, after validating once, you can start, stop and pause the sequence without validating in between. BUT, if you are changing the pattern sequence i.e., re configuring the pattern LUTs for a new pattern sequence, you need to re validate again. The DLPC350 can store only one pattern configuration at a time, and validation is required to ensure that the sequence is proper for correct operation of internal hardware. 

    Thanks & Regards,


  • In reply to Hirak Biswas:

    Hello Hirak,

    Understood. We change the pattern sequence in several situations. Then we realize that validations take about 1 second.

    For our application, speed is really important and that's why we would like to reduce this time as much as possible. Is there any way to do it?

    Thanks for your help,


  • In reply to Aitor Matilla:

    Hi Aitor, 

    Unfortunately this validation step is particularly important because it also configures the internal SW & HW for the pattern sequence. This step cannot be skipped. As you said, the validation time is highly dependent on the pattern sequence being validated. So if possible maybe you could shorten your pattern sequence, that way validation time can also come down. 

    Thanks & Regards,