DLP3030-Q1: DLP3030-Q1

Hi Libo,

Thank you for reaching out to the TI E2E forums. 

Normally we interface with the EVM through the DLPC120 Control Program so we do not use another MCU. 

Are you referring to the Piccolo SPI Command Guide for SPI commands?

3666.DLPU057_Piccolo_SPI_Command_Guide_201803.pdf

You can use the SPI command tab in the DLPC120 Control Program to test sending and receiving commands and responses as well as check the SPI Command Log.

Thanks,

Alex Chan

Hello Alex Chan！

     If I use the DLPC120 Control Program. I truly can recveive the response by logic analyzer. The control program actually send a series SPI signal. And the datasheet also shows our how to communicate with piccolo in a special protocol It means that we can control the slave by my MCU in SPI.I want to know the second question above.

Thanks

Libo Wang.

Hello Alex Chan！

Meanwhile if I use my MCU to control the Piccolo,and then I use control program to send  SPI command to piccolo, I also cannot receive response,but the backlight brightnees surely has been changed.

Thanks!

LIbo Wang

Hello Libo, 

Thanks for the latest updates. The team will get back to you by early next week. 

Regards,

Mayank

Hello Alex Chan！

     Ok,I can understand your mean.We have another question is that i can not change  the windows by control program---Send Rao SPI Command this function.If I write  data ff ff 01 00 00 01, and then I read it, I read 00 00 01 00 00 01,which is default setting.Pls help me how to work out this.

Hello Libo,

We will have to look into this matter. Thank you for your patience.

Regards,

John

Hi Libo,

Sorry for the delayed response.

Have you tried using these controls in the DLPC120 Control Program?

Thanks,

Alex Chan

Hello Alex Chan！

        I haven't tried this yet. I will try it lateter. But why I can't control the Piccolo by command, whether your datasheet is correct.

Hi Libo,

Sorry the documents may be a little confusing.

For example if I want to set the following settings, I sent the following in the Piccolo SPI Command.

Note how the command ID is 28 and not 50. 

You can also use the SPI command log to see what is being sent. The SPI command log will show communication whenever you use the GUI such as in the picture as well as when using the Piccolo SPI command feature.

Thanks,

Alex Chan

Hello Alex Chan！

   My command ID is 28，I can write successfull.But when I read in this command ID, I found that the featureis not changed. 

   Meanwhile, I use this function to change the offset. But I can't see any change with the naked eye.Is this phase shift adjustment an obvious one?

     And I find another question,compare with brightness ratio 20%(backlight value is 13107) and ratio is 30%(value is 19660). I found that the ratio 20% is obviously brighter than 30%，and the current is also larger than 30%. And the ratio 50% (value 32767) also exit the same situation. This happen to both my MCU and Control Program.

Thanks，

Tianye Xu

Hello Alex Chan！

  I test the relationship between current and brightness.RegisterData = 65535 * BrightnessDuty / 10000. Point 1，2，3 duty is 1556，2753，5701. And corresponding register value is 10197，18041，37361. Is my chip broken or is it your design problem.

Thanks!

Tianye Xu

Hello Tianye,

Please allow us until mid next week to consider this question. It does not appear that your chip is broken given the current performance. It may be that there is noise or some interference causing this issue. 

Regards,

Austin

Hello Tianye,

Please ensure you have the following settings applied.

Under the command list tab above the bezel offset, you need to select type as "Bezel Adjustment" and Lists select "Enable Bezel". By default, the system disables bezel adjustment. 

Then you can adjust the vertical or horizontal offset and you will see a noticeable shift in the displayed image. 

I will need some more time and information to look into the current and brightness relationship. Are you using a system from TI that has not been modified or recalibrated in any way? How are you measuring the brightness and current? What do you mean by duty cycle? The brightness is set by a parameter called "backlight" which is a 16 bit integer with a max value of 65535. 

Ideally the backlight value should have a linear relationship with brightness.

In terms of current, the relationship between backlight value and current is not linear. In order to dim the system, the LED driver has two operating modes, continuous mode and discontinuous mode. More can be learned in the following user guide. Discontinuous mode is not as efficient and there can be a lot of current but only a small amount goes through the LEDs to create light. 

7827.dlpa084 led driver app note.pdf

Thanks,

Alex Chan

Hello Alex Chan！

   Now, I can adjust the vertical or horizontal offset successfully.

  Although,the relationship between backlight value and current is not linear, the relationship between BackLight and lightness is must linear. When I set BackLight 9830 and 10485, I found that the display darkened. I doubt whether RBG parameters were modified in the calibration mode during the upper computer, which affected the brightness and backlight value.

Hi,

When you change the backlight from 9830 to 10485 does this number, the LDC index change? If the LDC index changes that means the brightness change is occurring on a transition between system settings we call coarse combinations which can commonly create a slight change in brightness due to pulses changing amplitude and current changing because of different system settings. Are you measuring the brightness and seeing a difference or just visually noticing the display darkening? How much of a brightness change are you seeing if you are measuring?

I know I have asked this before but this system is straight from TI and has not been modified or recalibrated in any way correct?

Thanks,

Alex Chan