We have Colibri Evaluation Board V3.2B board with Colibri iMX8QXP 2GB WB IT V1.0B module. We are using Colibri-iMX8X-V10B_Reference-Multimedia-Image-Tezi_5.3.0. We have problems and questions with the display interface. Firstly, our purpose is to have two independent hdmi outputs and drive two independent displays. What should we do for this? Can we use the vga port(X24) and lvds port(X18) on the eval board independently of each other and run two independent displays? Our second problem is that when we try to drive a 1280x1024@60 resolution image from the vga output on the eval board, the display flickers. How can we solve these problems? Thanks.
The vga port(X24) and the lvds port(X18) on the Colibri Evaluation board has the same signal source - parallel RGB interface of Colibri module, Please check eval board diagram for details.
So you can connect two displays but you will get the same picture on both of them.
However Colibri-iMX8X has a X2 connector where you can get an LVDS or MIPI-DSI signals. Please check chapters 5.6.2 LVDS and 5.6.3 Display Serial Interface (DSI) of Colibri-iMX8X datasheet.
Unfortunately Colibri Eval board does not have a mating connector. To overcame this problem we developed the Colibri iMX8X DSI to HDMI Adapter. You can create your own adapter if you wish to use an LVDS display.
As about display flickering - have you tried to adjust pixel clock? Or try to use another display and/or VGA cable?
Thank you for your recommendations. Will I be able to drive display from the DVI connector on the Colibri Evaluation Board V3.2B board when the Colibri iMX8X DSI to HDMI adapter is used? We tried everything for the drive display 1280x1024@60 resolution on VGA. While adjusting the resolution, we typed the vidargs parameters on the u-boot screen as below:
setenv vidargs video=DPI-1:1280x1024@60
and we have changed the weston.ini file as the below:
[core]
#gbm-format=argb8888
idle-time=0
#use-g2d=1
#xwayland=true
#enable-overlay-view=1
backend=drm-backend.so
#shell=fullscreen-shell.so
[shell]
#size=2560x1024
panel-position=none
locking=false
background-color=0x00ffffff
background-image=/etc/xdg/weston/background.png
background-type=centered
[libinput]
#touchscreen_calibrator=true
[output]
name=DPI-1
mode=1280x1024@60
#transform=180
# WIDTHxHEIGHT Resolution size width and height in pixels
# off Disables the output
# preferred Uses the preferred mode
# current Uses the current crt controller mode
#transform=180
#[screen-share]
#command=/usr/bin/weston --backend=rdp-backend.so --shell=fullscreen-shell.so --no-clients-resize
I think we are trying to fix the wrong things to adjust the resolution. What kind of changes do we need to make in order to work at the resolution we want?
Yes you can use carrier board DVI connector if you install DSI to HDMI adapter between Module X2 and Board X6 connector.
To adjust display timing and /or enable DSI to HDMI adapter you need to either update a Device Tree or use Device Tree Overlays. Please check here.