Announcement

Collapse
No announcement yet.

LVDS cable help

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • LVDS cable help

    I've got a bare panel (Sharp LQ10PX22) and a board Advantech PCM-9577 that both support LVDS. The Sharp monitor specifies "18(6xRGB)x2 bit parrallel data signals, four kinds of timing signals, and +5V DC supply voltage for TFT-LCD panel driving." The Advantech board's data sheet states it "supports 2 Channel (2 x 18bit) LVDS interface."

    LCD Pinout
    Mobo Pinout

    First question, are these compatible?
    Second question, what sort of cable do I use to connect it?

    The sharp monitor uses a Japan Aviation Electronics Industry Ltd KX14-80K2D receptacle and the Advantech board uses a Hirose DF13A-20DP-1.25V receptacle. I think I've done all I can do and now I'm in need of your expertise. Let me know if you need anything other specs (I found most of the data sheets). Thanks in advance.

  • #2
    That LCD pinout doesn't look like LVDS. Why do you think it is LVDS?
    Old Systems retired due to new car
    New system at design/prototype stage on BeagleBoard.

    Comment


    • #3
      yeah, that is not lvds display pinout, probably ttl I think...
      MY NEWEST INSTALL:modded infiniti fx with big screen

      first windows carpc install........my liquid cooled LVDS screen :D

      Comment


      • #4
        I guess I just kind of assumed it was since it matched the 2x18 of the LVDS of the mainboard. That is why I'm asking the community here which knows a lot more than me. Here is a link to the outputs available (i'm not including vga but it has a header too):

        Available headers

        Comment


        • #5
          It can be made to work. I'm running an 18 bit TTL panel from an LVDS output using a Advantech PCM3540 LVDS receiver to interface it.
          Old Systems retired due to new car
          New system at design/prototype stage on BeagleBoard.

          Comment


          • #6
            Ok, if you two agree it isn't LVDS then it must not be

            I think that explains why I couldn't figure out the conversion between the two pinouts. I'll take a look and see what I can figure out now. I'm sure I'll have more questions for you including what is the max length of a TTL "cable bundle" Thanks so much for your quick responses.

            Comment


            • #7
              Originally posted by Rob Withey View Post
              It can be made to work. I'm running an 18 bit TTL panel from an LVDS output using a Advantech PCM3540 LVDS receiver to interface it.
              Would it be better to the route described above or straight TTL to TTL. I'm guessing the straight shot would be best but I'll wait for the gurus to weigh in.

              Comment


              • #8
                That LCD pin-out is most likely an 18bit TTL, at least that's what the signals would suggest.

                If that's the case the the LCD and Controller would not be compatible.
                The controller's pin-out is LVDS (Low Voltage Differential Signal).

                You would need a controller that has an 18bit TTL output (to drive the LCD) and whatever input you are supplying from your PC (analog RGB (15-pin D-sub), DVI, or LVDS from your mother board).
                The controller also has to support the native resolution of the LCD (the 18bit TTL output has to match the LCD resolution which is 1024x768 for the LQ10PX22).

                There are two main types of display interfaces, LVDS and TTL. There are a few threads on here that describe the difference between the two if you're interested.
                Sailin
                ________________________________________
                CarPC Status:
                Planning.......[--------x-] 90%
                Parts..........[------x---] 70%
                Fabrication....[----x-----] 50%
                ________________________________________

                Comment


                • #9
                  Thanks for the info benedums.

                  I'm almost positive my board supports TTL as it has a pinout table that includes diagrams for:
                  16-bit DSTN
                  24-bit DSTN
                  18-bit TFT
                  24-bit TFT
                  36-bit TFT

                  In this case I'm guessing the TFT is equivalent to TTL. Is this a mistake on my part?

                  I'll defer to you guys again but I do believe my display is 36-bit as it includes RA(0-5) and RB(0-5) as well as GA, GB, BA, and BB. I'm just guessing here but 6x6 = 36 bit? Thanks again for all the help.

                  Comment


                  • #10
                    Originally posted by Lucky13ESP View Post
                    Thanks for the info benedums.

                    I'm almost positive my board supports TTL as it has a pinout table that includes diagrams for:
                    16-bit DSTN
                    24-bit DSTN
                    18-bit TFT
                    24-bit TFT
                    36-bit TFT

                    In this case I'm guessing the TFT is equivalent to TTL. Is this a mistake on my part?
                    TFT is the type of LCD (Thin Film Transistor) where TTL is the interface.
                    So TFT is not equal to TTL...

                    Most "new" motherboards that support LCD's (TFT, DSTN) do so with an LVDS interface, since that type of cable is less susceptible to EMI interference (TTL is more susceptible to interference).

                    There are several different formats of LVDS and TTL, each might include 16-bit thru 36-bit.
                    18-bit LVDS is not compatible with 18-bit TTL without a controller to convert it.

                    So it's likely that your MB only "directly" supports LVDS panels, unless you have a TTL connector on it, it probably only supports LVDS. Hence the need for a controller to convert the LVDS to TTL...
                    Sailin
                    ________________________________________
                    CarPC Status:
                    Planning.......[--------x-] 90%
                    Parts..........[------x---] 70%
                    Fabrication....[----x-----] 50%
                    ________________________________________

                    Comment


                    • #11
                      This page is from the user manual of the mobo. Available Headers

                      They appear to be different from the LVDS header.

                      Comment


                      • #12
                        what are the pin assignments of CN23 & CN18?
                        Sailin
                        ________________________________________
                        CarPC Status:
                        Planning.......[--------x-] 90%
                        Parts..........[------x---] 70%
                        Fabrication....[----x-----] 50%
                        ________________________________________

                        Comment


                        • #13

                          Comment


                          • #14
                            In the case that this is a 36 bit TTL output i've started matching up pinouts

                            I'm matching like so:

                            RA0 = R00
                            RA1 = R01

                            RB0 = R10
                            RB1 = R11

                            now for the trick part. I have these labels left over

                            On the LCD
                            CK (Dot Clock?)
                            Hsync (Latch Pulse?)
                            Vsync (First Line Marker?)
                            OHP-
                            ENAB

                            On the mobo
                            SHFCLK (Shift Clock?)
                            FLM (First Line Marker?)
                            M/DE (Display Enable?)
                            LP (Latch Pulse?)
                            ENAVEE

                            Let the matching game begin

                            Again, thanks for the help, I'm learning, albeit slowly

                            Comment


                            • #15
                              So is that from a motherboard or a controller board?

                              It looks like they split up the TTL interface between two connectors CN23 & CN18 which is a bit odd... none the less since the LCD is +5V you will not need to use the +3.3V... The ENAB on the LCD is probably the ENAVEE, CK could be SHFCLK, not sure where the Hsync and Vsync will mate to on the controller. and NC = No Connect...

                              I would be very surprised if this worked and didn't fry the controller or the LCD or both, so tread carefully.

                              It's best to find a controller that you know is compatible with the LCD...
                              Sailin
                              ________________________________________
                              CarPC Status:
                              Planning.......[--------x-] 90%
                              Parts..........[------x---] 70%
                              Fabrication....[----x-----] 50%
                              ________________________________________

                              Comment

                              Working...
                              X