Hello
Since we updated our BSP (built by ourselves) from version 1.4 to the latest version 2.3 we have the following problem. Sometimes, as soon as the OS takes over the display, after the bootloader has successfully shown the splashscreen, everything gets a color shift, either in the direction of yellow (blue color weaker) or in the direction of blue (red color weaker). This remains then until the system is powered off.
I used your keycolor picture and recorded the following situations (see attachement):
- Situation when everything works normally
- Color cast into yellow (with LDDS = 16)
- Color cast into yellow (with LDDS = 18)
The difference between LDDS 16 and 18 can be seen on the transition from the bad parts in the key image to the good ones.
It looks like the color resolution of one of the colors gets diminished sometimes. The color shift to blue is very seldom, but the shift to yellow occurs in about 5% of starting the system.
Our splashscreen settings look like that:
ss.fileaddr: 0x0 (FlashAddress with SplashScreen Data)
ss.filesize: 0 (Size of SplashScreen Data)
ss.enable: 1 (Enable SplashScreen)
ss.dbginfo: 0 (Enable DebugInfos)
ss.res: 0x0 (Reserved Flags)
ss.width: 800 (Display Width)
ss.height: 480 (Display Height)
ss.bpp: 16 (BitsPerPixel)
ss.ldds: 18 (LCD Lines Used)
ss.type: 1 (Display Type (0=Passive, 1=Active))
ss.color: 1 (0=Mono, 1=Color)
ss.dual: 0 (0=SinglePanel, 1=DualPanel)
ss.overlay: 0 (Overlay Enable)
ss.dpc: 0 (Double Pixel Clock)
ss.pcp: 0 (Pixel Clock Polarity)
ss.oep: 0 (Output Enable Polarity)
ss.hsp: 0 (Horizontal Sync Polarity)
ss.vsp: 0 (Vertical Sync Polarity)
ss.pclk: 33200000 (PixelClock (in Hz))
ss.hsw: 0 (Horizontal Sync Width)
ss.vsw: 0 (Vertical Sync Width)
ss.blw: 128 (Begin of Line Width)
ss.elw: 128 (End of Line Width)
ss.bfw: 22 (Begin of Frame Width)
ss.efw: 23 (End of Frame Width)
ss.acb: 256 (AC Bias Frequency)
ss.disp_gpio: 44 (Display On/Off Gpio)
ss.bl_gpio: 31 (BackLight On/Off Gpio)
ss.dispondelay: 0 (Display On Delay (ms))
ss.disp_pol: 1 (Display On/Off polarity)
ss.bl_pol: 1 (BackLight On/Off polarity)
ss.pcddiv: 1 (Enable Pixel Clock PreDivider)
ss.res: 0xFC (Reserved Flags)
ss.bsTeg: 0xF1612030 (LCD Buffer Strength Tegra)
I don’t have any idea what might cause this problem. With the BSP based on version 1.4 everything works without a problem. What could have changed since then that could cause that problem now? It looks like an uninitialized variable which causes the error sometimes and sometimes not.
Thanks for any help.