New Splashscreen on T20 is flickering

We recently introduced a new custom splashscreen image in our Wince7 T20 devices.
During boot, the splashscreen flickers on some occasions (you can see an example here).
They were supposed to be part of the launch of our new model year software version “MY2023” (which is stated in the splashscreen) and now we had to revert back to the old splashscreen until we solve this.

We already got a copy of your splash screen bmz converted application from the past and we applied it on the set of new bmp images prepared to be compatible with the converter (8bpp, etc).

We have now covered almost all the testing and comparisons on the devices and we are left with two options:

  • Either the source bmp images or the bmz converter for T20 are at fault, which is what I want to ask you (but it would be a bit strange as the same image does not give the issue on all the devices);
  • Or some other changes on our custom board we are investigating might be at fault (which again would be strange as the old splashscreen images don’t have this issue, and AFAIK they never had);

All the tests of updating the splash screen device have been performed with the toradex UpdateTool, either the one available on the device (6.0.14) or the copy we hold on our installation USB sticks (6.0.10), without notable differences.

Here I attached most of the files involved:

Please let me know if you need more information and how we can fix this issue.
Thank you

Colibri T20 256MB V1.2A
Custom Board
WinCE7 2.1

Could you please provide a BSP version of WEC 7 you are using? Could you also share your eboot SS settings?

Apparently I cannot edit the question anymore now that there is a reply, so I will add the missing info here:

Colibri T20 256MB V1.2A
Custom Board
WinCE7 BSP 2.1 (maybe it was not that clear above)

Follows the boot loader settings:

Config List:
*mac: Ethernet MAC Address
ip: IP Config
boot: Boot Config
ser: Serial Port Config
gpio: GPIOs Config
*hw: HW Version
dbg: Debug Config
*ss: SplasScreen Config
pex: Processor Extentions
karg: Kernel Arguments
sd: SD Card Config

set ss
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: 8 (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: 25175000 (PixelClock (in Hz))
ss.hsw: 96 (Horizontal Sync Width)
ss.vsw: 2 (Vertical Sync Width)
ss.blw: 48 (Begin of Line Width)
ss.elw: 16 (End of Line Width)
ss.bfw: 33 (Begin of Frame Width)
ss.efw: 10 (End of Frame Width)
ss.acb: 256 (AC Bias Frequency)
ss.disp_gpio: 198 (Display On/Off Gpio)
ss.bl_gpio: 6 (BackLight On/Off Gpio)
ss.dispondelay: 0 (Display On Delay (ms))
ss.disp_pol: 0 (Display On/Off polarity)
ss.bl_pol: 1 (BackLight On/Off polarity)
ss.pcddiv: 1 (Enable Pixel Clock PreDivider)

ss.res: 0xFC (Reserved Flags) (<- this is 0x0 in another device with same issue because i read the value from the ConfigBlockEditor utility instead of the bootloader)

ss.bsTeg: 0xFFFFFFFF (LCD Buffer Strength Tegra)

set hw
hw.vermaj: 1 (Major Version)
hw.vermin: 2 (Minor Version)
hw.variant: 0 (Variant Numer (stuffing options))
hw.prodid: 20 (Product ID)

set mac
mac.tid: 0x142D (Toradex MAC range ID)
mac.cid: 14763239 (Colibri MAC range ID)

splash screen settings.txt (2.6 KB)

I’ve converted your BMP file into BMZ and tested it with BSP v2.4. Everything works as expected with no artefacts. Please upgrade your BSP to the latest one.

Thank you Alex, I have confirmed that the BMZ you provided shows the same glitch in the same situations as the one we generated on our side.

I don’t think we are going to update our BSP to solve this. It won’t be feasible at least not very soon.
We still have other leads pointing us to the hardware, we will follow them for the moment.

Can you just test BSP v2.4 to be verify if display still flickering or not?

Hi @EnricoPompeiani , your Pixel clock value looks too low. DO you have your display datasheet available?

015005123AM-800480STMQW-T00-AMPIRE.pdf (764.8 KB)

Thank you.

Accursing to the provided datasheet pclk should be a 33.26Mhz while you set it to 25.17Mhz. Please try to set ss.pclk=33260000

Thank you very much!
I tested it and it seems to work very effectively (no collateral effects spotted so far).

I tested it by using the ConfigBlockUtility by hand. How can we introduce this fix programatically?

You can do it using eBoot Set ss.pclk command followed by by save ss commands (check this article). Then you can backup settings using the Update tool in command mode and use saved backup for production programming,