I have two questions.
I have the built-in Ethernet port on the BBB to be set for a static IP.
The network is just a patch cable from the ethernet port connected to an another device, which also has a static IP. There is no server, internet or dhcp. The BBB just sends UDP messages to the other device.
So I added the following lines to the /etc/network/interfaces file:
iface eth0 inet static
After a reboot, sometimes, ifconfig will show the static IP for eth0 and sometimes it does not. As if it is ignoring my interfaces setting.
Any ideas why the static IP might not be working, or, generally, how can I go about troubleshooting this issue?
Second question is about displaying graphics through the hdmi port.
I am currently installing the following packages over the latest BBB IoT release. None of these packages are set in stone - its just what I have at this stage.
apt install openbox obconf obmenu lxterminal tint2 leafpad pcmanfm lightdm nitrogen network-manager-gnome gnome-backgrounds
I would like to display a status screen on a monitor connected to the hdmi port. It would have 3 simple horizontal bars (to show percent usage data), some colored text, and colored indicator LEDs showing status.
Could you recommend a language and library?
I am thinking I will duplicate my existing UDP message to also send to localhost. This message contains the data I want to display. Then create a separate display program to listen for UDP messages and display the data on the hdmi port.
Is there a way to execute the echo 1 > /sys/class/leds/ name /brightness function from within the c program?
I know I could do a system() call, but that seems very slow. If that is not slow, then I will go ahead, but I just imagine shelling out takes quite a bit.
Well this depends…
The led class as an default-state option, so on startup you can force a default on/off…
Otherwise, system call is probally best…