DS90UB941AS-Q1: Can not detect MIPI signal when i using the Analog LaunchPAD

i confirm my mode0 and mode1 set and i give the mipi signal to the right port.

Hello,

What are the MIPI clock frequency, clock type (continuous?), and MODE strap settings?

Thanks,

Casey 

Hello:

     MIPI clock frequency:52MHZ

     clock type:continuous

     The SER DS90UB941 mode setting:

     1.DSI 4 Lanes input

     2.Splitter mode:normal operation

     3.DSI input enable

     4.COAX MODE:Enable FPD-LINK III for coaxial cabling

     5.CLOCK MODE:FPD-LINK III is generated from DSI clock.

     Besides,i know the MIPI Clock 52MHZ is lower than the DS90UB941 MIPI clock frequency demand.

     But the Analog LaunchPAD should detect the 52MHZ even if the frequency is not correct.Right?

     And i want to know,what should i do to config the Analog LaunchPAD,please give me a right way,and i will test if it works.

     Thanks!

Hello,

Frequency detection is done through 941AS - Analog LaunchPad is only reading this data through the 941AS registers. 52MHz DSI clock is too low for 941AS as you say and the frequency detection circuit may not function correctly at that rate.

Best Regards,

Casey 

Hello,

      Thank you Casey,then i will change my MIPI clock frequency and test if it will work.

      I will contact you if i have problem.

Hello Casey，

      With your suggestion,i change my MIPI clock type to continous,and my LVDS LCD can display now.

      But it's still have some problem.

     1.the color displayed is muddledness as below:

         Then i try to deal with the problem and i change a register from DS90UB941 as below:

          I change the VEDIO_18B_EN from 0 to 1,and then the color displayed is normal as below：

          But there still has a proble,the brightness displayed is very low.

          And i want to know with this situation,where is the problem？Please give me some suggestion and i will test.

          Thanks Casey.

Hello,

Is the panel backlight controlled by the FPD-Link devices? Usually this is not the case so I would check how to control the backlight from the panel side. 

Best Regards,

Casey 

Hello,

    But when i change  the VEDIO_18B_EN from 1 to 0,the color displayed is muddledness,what's wrong with this situation?

    The backlight is controlled by other circute,i change the backlight volt,there is no change.

    And when VEDIO_18B_EN is set to 0,the test pattern is ok.

    So i think there is porobably some wrong set by our MIPI signal,do you think so?

Hello,

Is the panel expecting 18 bit video or 24 bit video? Do you have a specification for the panel?

Best Regards,

Casey 

Hello

     24-bit.鑫航盛9寸IPS规格书-WD090SHL40AC-F6.pdf

Hello,

      Thank you Casey,i will try to test with your suggestion.

Hello，

       Casey,with your suggestion,my lcd display well,thank you so much!