We have built our own board using DM8148. It has to connect to an LCD display(640X480 - 33Mhz pix clk with DE only interface
6-bit per pixel). The board also supports HDMI out and we are getting display through that. But even after following TI doc or anything
available on net we are not able to get the display screen up on the LCD panel through Video Out 0/1/2 ports.
Is there a code snippet which we can execute at the end which will do all LCD related programming ?
Please help.
Regards,
/Muthu
Hi,
Can you please check you LCD timings in the LCD specifications and configure the same in VOut. Also i think you are using DE + Vsync signals to interface with your LCD.
Thanks,
Brijesh
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Brijesh,
Thanks. We had checked/prepared all LCD timings but not able to figure out where is the LCD VOut configuration
settings file/template/place-holder ? That is our question..
Wherever we think it should be configured, like by comparing with HDMI_out settings, Linux files for LCD out
we filled in places but nothing works!! We programmed PLLs, ?*LCD?* related registers etc.. But no signals coming
out of DM8148. We measured the LCD_out clock, in Linux it comes as 33Mhz(correct for the LCD panel we are using and
display is up), in WinCE7 no clock is coming or it is coming as 148Mhz which is too high , so LCD display does not show up.
We want a small code snippet which we want to execute at the end to ensure LCD signals are coming out of DM8148.
I do not understand why TI cannot give these kind of code snippets so that we customers of TI can use the
devices readily for every sub-system of the SoCs independent of third party SW stacks and OS'es
Hi Muthu,
How are you configuring timing for Vout0? Please confiure this in timings syfs attribute under displa0 folder. This will configure the Vout0 as per the timings you require. It is standard format for specifying timings for the display. Once you configure the timing, you enable the display by writing 1 to the enabled sysfs attributes under again display0. This is good enough for programming any display timings..
Brijesh Jadav
Hi Brijesh,
I am (Rajath) working along with Muthu.
What you suggested is for LINUX, we have seen it working already that is what he has mentioned in his posting.
Our problem is getting the same display working on WINEC7.Could you send us the same info for WINEC7.
In WINEC7 HDMI out is working fine but we have to get the DVO2 out to the LCD display.
We have copied the DISPLAY folder under BOOTLOADER and LCDC folder under SP_COMMON for AM387X_BSP(refered from AM33X BSP), but don't know what should be the the AM_DEVICE_LCDC address. Where can we get information on the LCD registers for setting the timings, FB base and ceiling values, panel setting etc.
All LCD timing parameters we have edited into LCD_panel STRUCT under LCDC.C file.