image size too large for 10.2 " screen

[Facel]

The manufacturer (OrigenAE) is using a technology developped by a compagny called EETI.
They provide a driver  for different OS:  https://www.eeti.com/drivers_Linux.html

I have installed the 'eGTouch_v2.5.11703.L.ma" linux driver on the very last version of moode (on a USBRidge signature)
The touch screen functionnality is working but is quite slow ...
 
The chapter 8.3 of the programming guide is about setting resolution but it does not modify anything for me.
image size is still too large

The xrandr command result is :'Can't open display'  !!!


The forum does not allow me to attach a pdf file (EETI_eGTouch_Linux_Programming_Guide_v2.5o.pdf)
This file is included into the tar.gz file of the linux driver

I must also say that this problem occurs immediatly during the boot

[steve4star]

You can try from your shell session…

DISPLAY=:0 xrandr

[Facel]

the result is :

DISPLAY=:0 xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1280 x 800, current 1280 x 800, maximum 1280 x 800
default connected 1280x800+0+0 0mm x 0mm
1280x800 0.00*

[TheOldPresbyope]

The manufacturer (OrigenAE) is using a technology developped by a compagny called EETI.
They provide a driver  for different OS:  https://www.eeti.com/drivers_Linux.html

I have installed the 'eGTouch_v2.5.11703.L.ma" linux driver on the very last version of moode (on a USBRidge signature)
The touch screen functionnality is working but is quite slow ...
 
The chapter 8.3 of the programming guide is about setting resolution but it does not modify anything for me.
image size is still too large

The xrandr command result is :'Can't open display'  !!!


The forum does not allow me to attach a pdf file (EETI_eGTouch_Linux_Programming_Guide_v2.5o.pdf)
This file is included into the tar.gz file of the linux driver

I must also say that this problem occurs immediatly during the boot

Sorry, no. The EETI driver is all about the touchscreen as an input device. Nothing to do with it as a display device.

I don''t know what to make of your first post where you said "The screen is connected via a VGA  /HDMI adapter." What is a VGA /HDMI adapter? What is the actual interface to the touchscreen?

It's perhaps uncommon but there are LCD screens out there which lie about their "native" resolution, especially those from anonymous Asian manufacturers which get boxed, labelled, and sold by some other entity. After all, those numbers reported by xrandr and its ilk come from the firmware in the display's HDMI interface---just something some contract programmer inserted into it.

What happens if you boot Raspberry Pi OS itself on your Pi with the touchscreen attached? Do you get the same overlap? I'm thinking you will, but there's always the chance that we'll learn something.

One heat-it-and-beat-it solution is to play with displaying images of differing geometries to figure out what the native screen geometry is and then set that manually in moOdeOS.

Not my cup of tea. More than 20 years ago I spent way too much time in the lab manually configuring Unix workstations for the big displays we invested in. Looked great when I was done but what a waste of my time.

Regards,
Kent

[Tim Curtis]

Oh I missed that part about the VGA/HDMI adapter. IMO not worth the time messing with an old analog VGA screen.

[Facel]

@TheOldPresbyope 
   Correct the EETI driver is for touchscreen
   The screen has an interface card with the follwing Inputs: VGA - USB - Power (12 volts) - IR
   This card has a unique output with a special cable that gos direct into the screen
   the HDMI/VGA adapter is located between the USBridge Sign and the Interface card  


I have done different scenarios including running the offical debian on the same hardware (USBridge Signature)

  - When I run moode the display is too large but the resolution appears to be correct
    ...the display is flattened vertically (=dislay is too large) , and this append from the very beginning during the boot !

  - When I run debian the display is OK (no deformation) (HDMI connected before booting)

   - When I run moode the display is again flattened vertically. (HDMI connected before booting)
     But when I unplug the HDMI connector from the USBSignature, then plug it into my Windows PC HDMI output the display is OK
     (with a different resolution ( 1920x1080) but completly correct)
     after that, when I plug back the HDMI connector into the USBSignature the display switch again to a 1280 x800 resolution but the image is OK (no deformation)

    Unplugging the HDMI from USBridge and plug it again into the USBridge does not modify the diplay (display still too large)

  - When I boot moode without any HDMI connected and after a while when is running normally (headless) , a connexion of the HDMI will prompt a correct display ...in this case the resolution is 640 x 480 !! (or 639 x 479 P/R=1)

  
    My understanding is that the resolution is automatically detected by the "screen" (screen + interface card)
    At the very beginning of the Boot for Moode OS, something happens that disturb or interfere with the resolution detection process of the screen

[Nutul]

@TheOldPresbyope 
   Correct the EETI driver is for touchscreen
   The screen has an interface card with the follwing Inputs: VGA - USB - Power (12 volts) - IR
   This card has a unique output with a special cable that gos direct into the screen
   the HDMI/VGA adapter is located between the USBridge Sign and the Interface card  


I have done different scenarios including running the offical debian on the same hardware (USBridge Signature)

  - When I run moode the display is too large but the resolution appears to be correct
    ...the display is flattened vertically (=dislay is too large) , and this append from the very beginning during the boot !

  - When I run debian the display is OK (no deformation) (HDMI connected before booting)

   - When I run moode the display is again flattened vertically. (HDMI connected before booting)
     But when I unplug the HDMI connector from the USBSignature, then plug it into my Windows PC HDMI output the display is OK
     (with a different resolution ( 1920x1080) but completly correct)
     after that, when I plug back the HDMI connector into the USBSignature the display switch again to a 1280 x800 resolution but the image is OK (no deformation)

    Unplugging the HDMI from USBridge and plug it again into the USBridge does not modify the diplay (display still too large)

  - When I boot moode without any HDMI connected and after a while when is running normally (headless) , a connexion of the HDMI will prompt a correct display ...in this case the resolution is 640 x 480 !! (or 639 x 479 P/R=1)

  
    My understanding is that the resolution is automatically detected by the "screen" (screen + interface card)
    At the very beginning of the Boot for Moode OS, something happens that disturb or interfere with the resolution detection process of the screen

It's complicated...

@TheOldPresbyope do you think this could somehow be mitigated (if not fixed, that is...) by some parameters to the boot-image...?
Of course it will render the installation dependent on the display, having to take care of it possibly after each upgrade, but nevertheless...

I fail to remember how to do that, though... and now I am too busy to search for it... Maybe also the OP can have a look into it?

[TheOldPresbyope]

@Facel 

Is there not a full version (e.g., with desktop) Raspberry Pi OS i(RaspiOS) image you can boot on this Allo USB Bridge?

True, RaspiOS has close to a pure debian root filesystem but it has its own kernel, drivers, and tweaks.

I assume you booted a full version of debian rather than a lite version---you do have a desktop displayed, right? I'm going to assume it's running either pure X11 or X11 under Wayland and not pure Wayland.

What does debian say the screen resolution is (width-in-pixels by heighth-in-pixels) when you say "the display is ok"?

For example:


- moOde 8.3.7 on a Pi3B+ driving an official 7" LCD touchscreen via DSI (bullseye release of underlying debian).

Code:

pi@home:~ $ DISPLAY=:0 xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 800 x 480, current 800 x 480, maximum 800 x 480
default connected 800x480+0+0 0mm x 0mm
  800x480        0.00*

- current RaspiOS on a PI400 driving my desktop monitor via HDMI (bookworm release of underlying debian)

Code:

kreed@pi400:~ $ DISPLAY=:0 xrandr
Screen 0: minimum 16 x 16, current 1920 x 1080, maximum 32767 x 32767
XWAYLAND4 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 510mm x 290mm
  1920x1080     59.96*+
  1440x1080     59.99  
  1400x1050     59.98  
  1280x1024     59.89  
  1280x960      59.94  
  1152x864      59.96  
  1024x768      59.92  
  800x600       59.86  
  640x480       59.38  
  320x240       59.52  
  1680x1050     59.95  
  1440x900      59.89  
  1280x800      59.81  
  720x480       59.71  
  640x400       59.95  
  320x200       58.96  
  1600x900      59.95  
  1368x768      59.88  
  1280x720      59.86  
  1024x576      59.90  
  864x486       59.92  
  720x400       59.55  
  640x350       59.77  

Extended Display Identification Data (EDID) is the metadata standard used by an HDMI interface in returning information about a connected display. That's how RaspiOS knows the resolutions of the desktop monitor I used in the above example.

RaspiOS can ignore this returned EDID information, substituting a set of EDID data of its own. If nothing else, we can try to fake it 'til we make it. with your touch screen display.

[aside]

We'll never know what the native resolution of your physical LCD panel is. You've got a blackbox HDMI (digiral) to VGA (analog) converter which is driving the VGA input port of the blackbox display interface which converts the VGA (analog) signals into the specific digital signals needed by the input lines of the physical LCD panel. By blackbox, I mean we have no idea what's inside.

[aside #2]

RaspiOS is transitioning to Wayland. For the time being we're ok, but in future moOde will be more dependent on Wayland, not X11. Different tricks may have to be played.

Ain't life grand?

Regards,
Kent

[Facel]

@Facel 

Is there not a full version (e.g., with desktop) Raspberry Pi OS i(RaspiOS) image you can boot on this Allo USB Bridge?
   => Yes I can load a lite version (32 or 64 bit) without desktop and tell you the result in my next post

True, RaspiOS has close to a pure debian root filesystem but it has its own kernel, drivers, and tweaks.

I assume you booted a full version of debian rather than a lite version---you do have a desktop displayed, right? I'm going to assume it's running either pure X11 or X11 under Wayland and not pure Wayland.
   => I have booted with the Legacy 64 bit version, with security update and desktop environnment

What does debian say the screen resolution is (width-in-pixels by heighth-in-pixels) when you say "the display is ok"?
   => "The display is ok" means that the display is NOT flattened horizontally, ie text on the extreme left and extreme right of the screen is totally displayed

Please find below the result of the Legacy 64 bit version with desktop
 DISPLAY=:0 xrandr

Screen 0: minimum 320 x 200, current 1280 x 800, maximum 2048 x 2048
HDMI-1 connected primary 1280x800+0+0 (normal left inverted right x axis y axis) 261mm x 163mm
   1280x800      60.01*+
   1920x1080     60.00    60.00    59.94
   1600x1200     60.00
   1680x1050     59.88
   1280x1024     75.02    60.02
   1440x900      59.90
   1280x720      60.00    59.94
   1024x768      75.03    70.07    60.00
   832x624       74.55
   800x600       72.19    75.00    60.32    56.25
   720x480       60.00    59.94
   640x480       75.00    72.81    66.67    60.00    59.94
   720x400       70.08



For example:


- moOde 8.3.7 on a Pi3B+ driving an official 7" LCD touchscreen via DSI (bullseye release of underlying debian).

Code:

pi@home:~ $ DISPLAY=:0 xrandr
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 800 x 480, current 800 x 480, maximum 800 x 480
default connected 800x480+0+0 0mm x 0mm
  800x480        0.00*

- current RaspiOS on a PI400 driving my desktop monitor via HDMI (bookworm release of underlying debian)

Code:

kreed@pi400:~ $ DISPLAY=:0 xrandr
Screen 0: minimum 16 x 16, current 1920 x 1080, maximum 32767 x 32767
XWAYLAND4 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 510mm x 290mm
  1920x1080     59.96*+
  1440x1080     59.99  
  1400x1050     59.98  
  1280x1024     59.89  
  1280x960      59.94  
  1152x864      59.96  
  1024x768      59.92  
  800x600       59.86  
  640x480       59.38  
  320x240       59.52  
  1680x1050     59.95  
  1440x900      59.89  
  1280x800      59.81  
  720x480       59.71  
  640x400       59.95  
  320x200       58.96  
  1600x900      59.95  
  1368x768      59.88  
  1280x720      59.86  
  1024x576      59.90  
  864x486       59.92  
  720x400       59.55  
  640x350       59.77  

Extended Display Identification Data (EDID) is the metadata standard used by an HDMI interface in returning information about a connected display. That's how RaspiOS knows the resolutions of the desktop monitor I used in the above example.

RaspiOS can ignore this returned EDID information, substituting a set of EDID data of its own. If nothing else, we can try to fake it 'til we make it. with your touch screen display.

[aside]

We'll never know what the native resolution of your physical LCD panel is. You've got a blackbox HDMI (digiral) to VGA (analog) converter which is driving the VGA input port of the blackbox display interface which converts the VGA (analog) signals into the specific digital signals needed by the input lines of the physical LCD panel. By blackbox, I mean we have no idea what's inside.

 => according to my screen doc, the native resolution version is 1280 x 800
[aside #2]

RaspiOS is transitioning to Wayland. For the time being we're ok, but in future moOde will be more dependent on Wayland, not X11. Different tricks may have to be played.

Ain't life grand?

Regards,
Kent

Thanks for your help, You can find my answers above in blue color

[Facel]

Installation of Rasperry PI OS (Legacy 64 bit - No Desktop)

Code:

DISPLAY=:0 xrandr
-bash: xrandr: command not found

No info with the display command via ssh    BUT ... during the boot ..

at the very beginning of the boot the screen display a quite large "rainbow colored" square (this does not happen at all during moode boot)
the during the but the display was not OK (text on the left cut) 
then during the boot (almost at the end) the display switched by itself to the "OK mode"