torz77

This was originally meant as a reply to a user having problems enabling openVFD on a Tannix T3-Mini, a device I happen to own. I have recently been through this journey myself, and having searched the forums, I cannot find a recent topic on how to build this for Armbian, so have decided to make a new post that may be of use to some.
 
Hold on to your hat, because this is going to be long.
 
Caveats
These instructions are, specifically, for the Tannix TX3-Mini. However, with a bit of fiddling, the general approach should work for any supported TV Box. I have added notes where you will need to look to edit a different file for your specific device There are many, many variants of the TX3-Mini out there. What works for me, may not work for you. Do not expect any help or support from me, I am just posting this as a courtesy for how I got this working... your mileage may vary. I am not going to troubleshoot anyone's issues These instructions are quite verbose, as they may also help users of other TV Boxes to get their displays working. It also may not. Like I say, I am not here to be tech support, but we can all agree not having a display stuck on "boot" is a nice thing to have As this is a kernel module it will most likely stop working after each kernel update. You will probably want to create a DKMS to rebuild the module whenever you download a new kernel. This is outside of scope here. Use Google. At the end of this, if all goes well, you will have a display showing the current time. If you want to do more with the display then this is outside of scope and you will need to look elsewhere. However, this link is useful for how to trigger the icons: https://github.com/arthur-liberman/linux_openvfd/blob/master/led_control.txt (note: only items 1 to 6 are valid for the tx3-mini) A lot of this can be done in a chroot, but the actual building of the kernel module itself must be done on the target device. To simplify things all of these instructions are to be executed on the device itself. If you want to do this in a chroot, then knock yourself out, but you are on your own.  
My setup
At the time of writing, these instructions are confirmed working for the 7 Segment display and all icons on:
Tannix T3-Mini S905w with 2GB RAM Armbian 25.11 Kernel 6.12.48-current-meson64 Debian stable (trixie) (13)  
Instructions
Note: Every code block here is meant to be pasted and executed in one go, even the multi-line blocks
We will work from the home folder to keep things simple. Don't worry, there will be no clutter as we will remove files we no longer require as we go
cd ~ Device Tree Blob
The first thing we are going to want to do is enable kernel support for openvfd in our DTB. Normally I'd do this with an overlay, but this does not appear to be enabled on the aml-s9xx-box image, so we will apply an overlay to the DTB directly:
Install the device tree compiler: sudo apt install -y device-tree-compiler --no-install-recommends Back up the existing DTB (if anything goes wrong you can always just restore the backed up DTB) :
Note: If your device is not a Tanix T3-Mini, then you will want to amend the following to point to the actual DTB you are using (you can find this in '/boot/extlinux/extlinux.conf') sudo cp /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb.orig  
Create the overlay source code: cat << EOF > ~/openvfd.dts /dts-v1/; /plugin/; / { fragment@0 { target-path = "/"; __overlay__ { openvfd { compatible = "open,vfd"; dev_name = "openvfd"; status = "okay"; }; }; }; }; EOF Compile the overlay: dtc -@ -I dts -O dtb -o ~/openvfd.dtbo ~/openvfd.dts  
Merge the overlay into your DTB:
Note: If your device is not a Tanix T3-Mini, then you will want to amend the following to point to the actual DTB you are using sudo fdtoverlay -i /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb -o /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb ~/openvfd.dtbo Delete the overlay source: rm ~/openvfd.dts [Optional] Delete the compiled overlay:
If your build is static (that is, you will never pull an updated DTB through apt) then you can also delete the compiled .dtbo overlay file. I prefer to keep this around, as you can just re-patch the new DTB with the "sudo fdtoverlay ..." command above. It is also possible to automate the update of a newly installed DTB file by creating a postinst.d script, but that is outside of the scope of this document. Google is your friend. rm ~/openvfd.dtbo  
Reboot so when we load the module later, our device knows what to do with it sudo reboot now  
Once your device has been rebooted, you can confirm that your change has been applied correctly with the following command: dtc -I fs -O dts /proc/device-tree | grep -A3 openvfd Again, this will generate a lot of warnings! This is normal. At the end of the warnings you should see the openvfd entry that you added to your DTS in the earlier step. If you do not, then you have not edited the file correctly, and you should go back and try again.  
OpenVFD Config file
We need to create a configuration file which tells the OpenVFD module which GPIO pins are connected to the LCD display. We put this in the /etc folder as this is where we should be storing system configuration files for *deb based systems
The contents of this file were extracted from  https://github.com/arthur-liberman/vfd-configurations  so if you are using a different device, you must replace the following config with the relevant one from the link. If you are having issues with your config not working, direct them to the repo owner, not me. I do not know your device or what may be wrong.
Note: I remove the final functions='usb colon eth wifi' line as whilst the driver works fine with it included, it generates errors/warnings, which I would rather not see, and it appears to serve no purpose for Armbian
Execute the following to generate the config for the TX3-Mini
Note: If your device is not a Tanix T3-Mini do not execute the following. Instead, find your config at https://github.com/arthur-liberman/vfd-configurations and save it as /etc/openvfd.conf sudo bash -c "cat << 'EOF' > /etc/openvfd.conf vfd_gpio_clk='0,76,0' vfd_gpio_dat='0,75,0' vfd_gpio_stb='1,4,0' vfd_chars='4,3,2,1,0' vfd_dot_bits='0,1,3,2,4,5,6' vfd_display_type='0x01,0x00,0x00,0x00' EOF"  
Build the Kernel Module
Now for the nitty gritty, we need to build the kernel module.
The first thing we need is the kernel headers.
Note: the headers version must match your installed kernel version exactly. Do not try installing the headers for a different kernel version. You will run into issues
If you are on a standard image, or your kernel has been upgraded since you built your image, this is straightforward: sudo apt install linux-headers-$(uname -r) However, if you have built the image yourself, and you have not upgraded your kernel, then most likely the version available from the apt repository will not be compatible and your build may fail or the driver may not work at all. In these instances, you will need to go back to your build system and add the following switch to your ./compile.sh command: INSTALL_HEADERS=yes  
Install the required build tools
sudo apt install -y git build-essential --no-install-recommends  
Clone the openvfd repo.
At the time of writing the openvfd repo is not compatible with later Linux kernels. I have raised a PR against the repo to enable support, however it has not yet been accepted. If/when it is accepted I will be deleting my fork of the repo, but in the meantime, you can clone my fork with:
git clone https://github.com/torzdf/linux_openvfd.git ~/linux_openvfd If the above does not work, it is because I have deleted my fork as the changes have been merged, and I am unable to come back and edit this post. If this is the case then run the following:
Note: DO NOT run the next line, if the above git clone worked
git clone https://github.com/arthur-liberman/linux_openvfd.git ~/linux_openvfd  
Enter the driver folder of the cloned repo
cd ~/linux_openvfd/driver  
Create a Makefile. The provided Makefile will not work, so we need to replace it with our own:
cat << 'EOF' > ./Makefile ifeq ($(KERNELRELEASE),) PWD = $(shell pwd) KERNELDIR = /lib/modules/`uname -r`/build modules: $(MAKE) -C $(KERNELDIR) M=$(PWD) modules modules_install: $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install clean: rm -rf *.o *.ko .tmp_versions *.mod.c modules.order Module.symvers ssd253x-ts.* else obj-m := openvfd.o openvfd-objs += protocols/i2c_sw.o openvfd-objs += protocols/i2c_hw.o openvfd-objs += protocols/spi_sw.o openvfd-objs += controllers/dummy.o openvfd-objs += controllers/seg7_ctrl.o openvfd-objs += controllers/fd628.o openvfd-objs += controllers/fd650.o openvfd-objs += controllers/hd44780.o openvfd-objs += controllers/gfx_mono_ctrl.o openvfd-objs += controllers/ssd1306.o openvfd-objs += controllers/pcd8544.o openvfd-objs += controllers/il3829.o openvfd-objs += openvfd_drv.o endif EOF  
Compile the kernel module:
make -j$(nproc)  
Install the kernel module:
sudo make modules_install  
Update the kernel modules:
sudo depmod -a  
Create the helper service
Next we need to compile and install the helper service
Enter the folder that contains the source code for the helper service: cd ~/linux_openvfd  
Build the helper service: make OpenVFDService  
Make the helper service executable: chmod +x OpenVFDService  
Install the helper service: sudo cp OpenVFDService /usr/bin/  
Clean up
We have built everything we need from the OpenVFD repo, so we can get rid of the source code
Go back to our home folder and delete the source code cd ~ && sudo rm -r linux_openvfd  
systemd Service file
The final step. We need to create a service file that will load the kernel module, launch the helper service, and enable it on boot
Create the systemd service file:
note: If you prefer a 12 hour clock rather than a 24 hour clock, edit the 'Environment="OPTS=-24h"' line to 'Environment="OPTS=-12h"' sudo bash -c 'cat << '\''EOF'\'' > /etc/systemd/system/openvfd.service [Unit] Description=openvfd Wants=network-online.target [Service] Type=simple Environment="OPTS=-24h" ExecStartPre=/usr/bin/sh -c ". /etc/openvfd.conf; /usr/sbin/modprobe openvfd vfd_gpio_clk=$vfd_gpio_clk vfd_gpio_dat=$vfd_gpio_dat vfd_gpio_stb=$vfd_gpio_stb vfd_chars=$vfd_chars vfd_dot_bits=$vfd_dot_bits vfd_display_type=$vfd_display_type;" ExecStart=/usr/bin/OpenVFDService $OPTS & ExecStop=/usr/bin/killall OpenVFDService ExecStopPost=-/usr/sbin/rmmod openvfd [Install] WantedBy=multi-user.target EOF'  
Reload the systemd daemon: sudo systemctl daemon-reload  
Start the openvfd service: sudo systemctl start openvfd.service At this point your LCD should now be showing the time. If it is not, you can check for errors with: sudo systemctl status openvfd.service  
Enable the service at boot: sudo systemctl enable openvfd.service  
 
And that's it. If all has gone well, you now have a working LCD Display for your TV Box running a recent Armbian build

 

I apologize. I have not read what you wrote earlier.
Please write whatever you see fit your work can be very useful. Success to you in your endeavor.

Simply mark whatever you want to quote and a box will appear to click:

This was originally meant as a reply to a user having problems enabling openVFD on a Tannix T3-Mini, a device I happen to own. I have recently been through this journey myself, and having searched the forums, I cannot find a recent topic on how to build this for Armbian, so have decided to make a new post that may be of use to some.
 
Hold on to your hat, because this is going to be long.
 
Caveats
These instructions are, specifically, for the Tannix TX3-Mini. However, with a bit of fiddling, the general approach should work for any supported TV Box. I have added notes where you will need to look to edit a different file for your specific device There are many, many variants of the TX3-Mini out there. What works for me, may not work for you. Do not expect any help or support from me, I am just posting this as a courtesy for how I got this working... your mileage may vary. I am not going to troubleshoot anyone's issues These instructions are quite verbose, as they may also help users of other TV Boxes to get their displays working. It also may not. Like I say, I am not here to be tech support, but we can all agree not having a display stuck on "boot" is a nice thing to have As this is a kernel module it will most likely stop working after each kernel update. You will probably want to create a DKMS to rebuild the module whenever you download a new kernel. This is outside of scope here. Use Google. At the end of this, if all goes well, you will have a display showing the current time. If you want to do more with the display then this is outside of scope and you will need to look elsewhere. However, this link is useful for how to trigger the icons: https://github.com/arthur-liberman/linux_openvfd/blob/master/led_control.txt (note: only items 1 to 6 are valid for the tx3-mini) A lot of this can be done in a chroot, but the actual building of the kernel module itself must be done on the target device. To simplify things all of these instructions are to be executed on the device itself. If you want to do this in a chroot, then knock yourself out, but you are on your own.  
My setup
At the time of writing, these instructions are confirmed working for the 7 Segment display and all icons on:
Tannix T3-Mini S905w with 2GB RAM Armbian 25.11 Kernel 6.12.48-current-meson64 Debian stable (trixie) (13)  
Instructions
Note: Every code block here is meant to be pasted and executed in one go, even the multi-line blocks
We will work from the home folder to keep things simple. Don't worry, there will be no clutter as we will remove files we no longer require as we go
cd ~ Device Tree Blob
The first thing we are going to want to do is enable kernel support for openvfd in our DTB. Normally I'd do this with an overlay, but this does not appear to be enabled on the aml-s9xx-box image, so we will apply an overlay to the DTB directly:
Install the device tree compiler: sudo apt install -y device-tree-compiler --no-install-recommends Back up the existing DTB (if anything goes wrong you can always just restore the backed up DTB) :
Note: If your device is not a Tanix T3-Mini, then you will want to amend the following to point to the actual DTB you are using (you can find this in '/boot/extlinux/extlinux.conf') sudo cp /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb.orig  
Create the overlay source code: cat << EOF > ~/openvfd.dts /dts-v1/; /plugin/; / { fragment@0 { target-path = "/"; __overlay__ { openvfd { compatible = "open,vfd"; dev_name = "openvfd"; status = "okay"; }; }; }; }; EOF Compile the overlay: dtc -@ -I dts -O dtb -o ~/openvfd.dtbo ~/openvfd.dts  
Merge the overlay into your DTB:
Note: If your device is not a Tanix T3-Mini, then you will want to amend the following to point to the actual DTB you are using sudo fdtoverlay -i /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb -o /boot/dtb/amlogic/meson-gxl-s905w-tx3-mini.dtb ~/openvfd.dtbo Delete the overlay source: rm ~/openvfd.dts [Optional] Delete the compiled overlay:
If your build is static (that is, you will never pull an updated DTB through apt) then you can also delete the compiled .dtbo overlay file. I prefer to keep this around, as you can just re-patch the new DTB with the "sudo fdtoverlay ..." command above. It is also possible to automate the update of a newly installed DTB file by creating a postinst.d script, but that is outside of the scope of this document. Google is your friend. rm ~/openvfd.dtbo  
Reboot so when we load the module later, our device knows what to do with it sudo reboot now  
Once your device has been rebooted, you can confirm that your change has been applied correctly with the following command: dtc -I fs -O dts /proc/device-tree | grep -A3 openvfd Again, this will generate a lot of warnings! This is normal. At the end of the warnings you should see the openvfd entry that you added to your DTS in the earlier step. If you do not, then you have not edited the file correctly, and you should go back and try again.  
OpenVFD Config file
We need to create a configuration file which tells the OpenVFD module which GPIO pins are connected to the LCD display. We put this in the /etc folder as this is where we should be storing system configuration files for *deb based systems
The contents of this file were extracted from  https://github.com/arthur-liberman/vfd-configurations  so if you are using a different device, you must replace the following config with the relevant one from the link. If you are having issues with your config not working, direct them to the repo owner, not me. I do not know your device or what may be wrong.
Note: I remove the final functions='usb colon eth wifi' line as whilst the driver works fine with it included, it generates errors/warnings, which I would rather not see, and it appears to serve no purpose for Armbian
Execute the following to generate the config for the TX3-Mini
Note: If your device is not a Tanix T3-Mini do not execute the following. Instead, find your config at https://github.com/arthur-liberman/vfd-configurations and save it as /etc/openvfd.conf sudo bash -c "cat << 'EOF' > /etc/openvfd.conf vfd_gpio_clk='0,76,0' vfd_gpio_dat='0,75,0' vfd_gpio_stb='1,4,0' vfd_chars='4,3,2,1,0' vfd_dot_bits='0,1,3,2,4,5,6' vfd_display_type='0x01,0x00,0x00,0x00' EOF"  
Build the Kernel Module
Now for the nitty gritty, we need to build the kernel module.
The first thing we need is the kernel headers.
Note: the headers version must match your installed kernel version exactly. Do not try installing the headers for a different kernel version. You will run into issues
If you are on a standard image, or your kernel has been upgraded since you built your image, this is straightforward: sudo apt install linux-headers-$(uname -r) However, if you have built the image yourself, and you have not upgraded your kernel, then most likely the version available from the apt repository will not be compatible and your build may fail or the driver may not work at all. In these instances, you will need to go back to your build system and add the following switch to your ./compile.sh command: INSTALL_HEADERS=yes  
Install the required build tools
sudo apt install -y git build-essential --no-install-recommends  
Clone the openvfd repo.
At the time of writing the openvfd repo is not compatible with later Linux kernels. I have raised a PR against the repo to enable support, however it has not yet been accepted. If/when it is accepted I will be deleting my fork of the repo, but in the meantime, you can clone my fork with:
git clone https://github.com/torzdf/linux_openvfd.git ~/linux_openvfd If the above does not work, it is because I have deleted my fork as the changes have been merged, and I am unable to come back and edit this post. If this is the case then run the following:
Note: DO NOT run the next line, if the above git clone worked
git clone https://github.com/arthur-liberman/linux_openvfd.git ~/linux_openvfd  
Enter the driver folder of the cloned repo
cd ~/linux_openvfd/driver  
Create a Makefile. The provided Makefile will not work, so we need to replace it with our own:
cat << 'EOF' > ./Makefile ifeq ($(KERNELRELEASE),) PWD = $(shell pwd) KERNELDIR = /lib/modules/`uname -r`/build modules: $(MAKE) -C $(KERNELDIR) M=$(PWD) modules modules_install: $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install clean: rm -rf *.o *.ko .tmp_versions *.mod.c modules.order Module.symvers ssd253x-ts.* else obj-m := openvfd.o openvfd-objs += protocols/i2c_sw.o openvfd-objs += protocols/i2c_hw.o openvfd-objs += protocols/spi_sw.o openvfd-objs += controllers/dummy.o openvfd-objs += controllers/seg7_ctrl.o openvfd-objs += controllers/fd628.o openvfd-objs += controllers/fd650.o openvfd-objs += controllers/hd44780.o openvfd-objs += controllers/gfx_mono_ctrl.o openvfd-objs += controllers/ssd1306.o openvfd-objs += controllers/pcd8544.o openvfd-objs += controllers/il3829.o openvfd-objs += openvfd_drv.o endif EOF  
Compile the kernel module:
make -j$(nproc)  
Install the kernel module:
sudo make modules_install  
Update the kernel modules:
sudo depmod -a  
Create the helper service
Next we need to compile and install the helper service
Enter the folder that contains the source code for the helper service: cd ~/linux_openvfd  
Build the helper service: make OpenVFDService  
Make the helper service executable: chmod +x OpenVFDService  
Install the helper service: sudo cp OpenVFDService /usr/bin/  
Clean up
We have built everything we need from the OpenVFD repo, so we can get rid of the source code
Go back to our home folder and delete the source code cd ~ && sudo rm -r linux_openvfd  
systemd Service file
The final step. We need to create a service file that will load the kernel module, launch the helper service, and enable it on boot
Create the systemd service file:
note: If you prefer a 12 hour clock rather than a 24 hour clock, edit the 'Environment="OPTS=-24h"' line to 'Environment="OPTS=-12h"' sudo bash -c 'cat << '\''EOF'\'' > /etc/systemd/system/openvfd.service [Unit] Description=openvfd Wants=network-online.target [Service] Type=simple Environment="OPTS=-24h" ExecStartPre=/usr/bin/sh -c ". /etc/openvfd.conf; /usr/sbin/modprobe openvfd vfd_gpio_clk=$vfd_gpio_clk vfd_gpio_dat=$vfd_gpio_dat vfd_gpio_stb=$vfd_gpio_stb vfd_chars=$vfd_chars vfd_dot_bits=$vfd_dot_bits vfd_display_type=$vfd_display_type;" ExecStart=/usr/bin/OpenVFDService $OPTS & ExecStop=/usr/bin/killall OpenVFDService ExecStopPost=-/usr/sbin/rmmod openvfd [Install] WantedBy=multi-user.target EOF'  
Reload the systemd daemon: sudo systemctl daemon-reload  
Start the openvfd service: sudo systemctl start openvfd.service At this point your LCD should now be showing the time. If it is not, you can check for errors with: sudo systemctl status openvfd.service  
Enable the service at boot: sudo systemctl enable openvfd.service  
 
And that's it. If all has gone well, you now have a working LCD Display for your TV Box running a recent Armbian build