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Last Post 31 Aug 2015 12:45 PM by  Adam Ford
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chad.grant
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Posts:18


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27 Aug 2015 10:11 AM

    Because of the i.MX31 end of life we are trying to move to the DM3730 SOM-LV.

    On the i.MX31 we used "video-init 5 16", and those default settings worked great. No such luck with the DM3730, "video-init 5 16" is close because I can see some of the right colors, but there is a lot of flicker and shadows.

    I can use "info video 5" command on the DM3730 (runnig LogicLoader 2.5.2) and I get:

    Name:           LQ036Q1DA01
    Number:         3
    Resolution:     320 x 240
    DISPC_CONTROL  (0x48050440): 0x00018109
    DISPC_SIZE_LCD (0x4805047c): 0x00ef013f
    DISPC_GFX_SIZE (0x4805048c): 0x00ef013f
    DISPC_TIMING_H (0x48050464): 0x01401414
    DISPC_TIMING_V (0x48050468): 0x00300302
    DISPC_DIVISOR  (0x48050470): 0x00010004
    DISPC_CONFIG   (0x48050444): 0x00000000
    DISPC_POL_FREQ (0x4805046c): 0x00000000
    CM_CLKSEL_DSS  (0x48004e40): 0x00001009
    DISPC_GFX_BA0  (0x48050480): 0x80400000


    On the i.MX31 (running LogicLoader 2.4.14) "info video" returns bad argument. After finding and reading through AN502_LogicPD_DevKit_LVDS_Integration, I thought I could just examine the memory address on the i.MX31 and see what values were working. But the "x" command always hangs - even when I just try to run the examples from the 2.4 LoLo command document.

    How can I figure out what values are loaded with "video-init 5 16" on the i.MX31?

    Adam Ford
    Advanced Member
    Advanced Member
    Posts:754


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    27 Aug 2015 10:24 AM
    The registers you're reading and writing to the DM37 won't be the same as the registers you're reading and writing to the i.MX31.The registers you list are specific DM37 display subsystem registers.

    Let me try to reproduce the issue, and see if I can come up with a better solution for you.

    adam
    Adam Ford
    Advanced Member
    Advanced Member
    Posts:754


    --
    27 Aug 2015 10:36 AM
    Looking at your message, I am a little confused as to which display you are trying to use.

    video-init 5 16 should initialize the screen for 640x480

    Display 3 is LQ036Q1DA01 which is 320x240.

    Can you clarify which display you are using?
    chad.grant
    New Member
    New Member
    Posts:18


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    27 Aug 2015 10:42 AM

    That's my bad. I am using a 640x480 display. I went through and saved all of the video settings trying to just get more information from them. What actually gives me flicker is:

    losh> info video 5



    Name:           LQ64D343


    Number:         5


    Resolution:     640 x 480


    DISPC_CONTROL  (0x48050440): 0x00018109


    DISPC_SIZE_LCD (0x4805047c): 0x01df027f


    DISPC_GFX_SIZE (0x4805048c): 0x01df027f


    DISPC_TIMING_H (0x48050464): 0x01908931


    DISPC_TIMING_V (0x48050468): 0x02302002


    DISPC_DIVISOR  (0x48050470): 0x00010004


    DISPC_CONFIG   (0x48050444): 0x00000000


    DISPC_POL_FREQ (0x4805046c): 0x00000000


    CM_CLKSEL_DSS  (0x48004e40): 0x00001009


    DISPC_GFX_BA0  (0x48050480): 0x80400000


     

    Also video-init 7 16 works pretty similar which would make sense because the info video 7 gave all the same values.

    The screen(s) that I want to use are the Kyocera THG057V and the Mitsubishi AA057VG12. With the i.MX31 video-init 5 16 works for both of them.

    Thanks for your help!

    Adam Ford
    Advanced Member
    Advanced Member
    Posts:754


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    27 Aug 2015 11:34 AM
    Since I don't have those exact screens to test, I'll do my best to help.

    First, you'll need the data sheets for your respective displays. Your display may vary a bit, but the stock settings for display 5 are as follows:

    data_lines: 16
    x_res: 640
    y_res: 480
    pixel_clock: 27000
    hsw: 48
    hfp: 24
    hbp: 135
    vsw: 1
    vfp: 34
    vbp: 34

    Most likely these are slightly different for your displays. You'll also need to know if the data is latched on the rising edge or falling edge of the signals.

    The DM3730 Technical reference manual describes the DM37 registers you were inquiring: http://www.ti.com/lit/pdf/sprugn4


    We have an app note that covers the basics, but I can try to help. The App note is listed here: http://support.logicpd.com/DesktopM...ntryId=588
    Section 6.4 describes how to configure the LCD with Lolo and the above reference manual describes how the following are defined and what they mean:

    DISPC_CONTROL (0x48050440): 0x00018109
    DISPC_SIZE_LCD (0x4805047c): 0x00ef013f
    DISPC_GFX_SIZE (0x4805048c): 0x00ef013f
    DISPC_TIMING_H (0x48050464): 0x01401414
    DISPC_TIMING_V (0x48050468): 0x00300302
    DISPC_DIVISOR (0x48050470): 0x00010004
    DISPC_CONFIG (0x48050444): 0x00000000
    DISPC_POL_FREQ (0x4805046c): 0x00000000
    CM_CLKSEL_DSS (0x48004e40): 0x00001009
    DISPC_GFX_BA0 (0x48050480): 0x80400000


    For example Table 7-150 on page 1823 of it describes the register bits and how they go together and what each of the bits mean. Disecting each of the registers will give you an idea of how
    data_lines: 16
    x_res: 640
    y_res: 480
    pixel_clock: 27000
    hsw: 48
    hfp: 24
    hbp: 135
    vsw: 1
    vfp: 34
    vbp: 34

    becomes

    DISPC_CONTROL (0x48050440): 0x00018109
    DISPC_SIZE_LCD (0x4805047c): 0x00ef013f
    DISPC_GFX_SIZE (0x4805048c): 0x00ef013f
    DISPC_TIMING_H (0x48050464): 0x01401414
    DISPC_TIMING_V (0x48050468): 0x00300302
    DISPC_DIVISOR (0x48050470): 0x00010004
    DISPC_CONFIG (0x48050444): 0x00000000
    DISPC_POL_FREQ (0x4805046c): 0x00000000
    CM_CLKSEL_DSS (0x48004e40): 0x00001009
    DISPC_GFX_BA0 (0x48050480): 0x80400000

    Let me know if I can help further.

    We do have a support contract option if you want us to review your changes, etc. I would be willing to throw in setting up your displays if you're able to send me the hardware.

    adam
    chad.grant
    New Member
    New Member
    Posts:18


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    31 Aug 2015 12:07 PM

    Thanks for your help Adam.

    With the DM3730 reference manual and a logic analyzer I was able to poke around till I found the settings that needed to be tweaked.

    Adam Ford
    Advanced Member
    Advanced Member
    Posts:754


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    31 Aug 2015 12:45 PM
    Great! I am glad it worked out for you.

    adam
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