VOUT[0] into an LCD

dal wheeler

I have a question about the DM8168 VOUT[0] video modes. Trying to connect that port to drive an LCD; was wondering about the modes available to do that. Propose to have the 24 bit out going into a 75LVDS83B transmitter going into an 18 bit LCD panel.

I’m a bit confused as to which pins act as HSYNC/VSYNC in which modes.

Anyone gone through this exercise?

-Dal

over 13 years ago

0 Brijesh Jadav over 13 years ago

TI__Guru**** 476595 points

Hi,

We have 16 bit and 24 bit interface for discrete sync mode and 8, 16, 24 bit interface for embedded sync mode for vout0. There are separate pins for hsync/vsync/fid. I believe when you say 18bit LCD, it means RGB666. If it is the case, you can use 24 bit interface and connect it to 18 bit lcd by dropping 2bit lsb in each color components.

Thanks,

Brijesh Jadav

0 Steve Clynes over 13 years ago

TI__Mastermind 43875 points

Dal,

Have a look at this wiki page. It was originally written for OMAP but is completely relevant to the DM81xx devices too.

http://processors.wiki.ti.com/index.php/LCD_connectivity

BR,

Steve

0 dal wheeler over 13 years ago in reply to Steve Clynes

Intellectual 610 points

Thanks! I used that when I interfaced a few different LCD's to the beagleboard, and plan to use the same method. I'm confused about the role of VSYNC and HSYNC, and which pins do that during the 24bit mode. Does AM9 and AN9 work during that mode? Reading in the datasheet it seems that it can be on other pins too, depending on the mode called? Also, in RGB[2-9];would bit 9 be the MSB in this 24 bit mode?

0 Steve Clynes over 13 years ago in reply to dal wheeler

TI__Mastermind 43875 points

There are discrete H & V sync signals and are available regardless of the output mode.

As you note they are available on different output pins depending on which other device level functions you need.

Yes, you use the upper 8 bits of the 10 bit output if you only need 8 bits. Likewise if your LCD is only 18 bit then you would use the upper 6 bits of each output color channel.

BR,

Steve

0 dal wheeler over 13 years ago in reply to Steve Clynes

Intellectual 610 points

http://e2e.ti.com/support/dsp/integra_dsparm/f/625/t/124583.aspx

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VOUT[0] into an LCD