January 2019

Turn off HDMI on Pi-Star (Easier)

Here’s an even easier way to turn off HDMI on your Pi-Star image running under Raspbian. If you’re running one of the Pi-Star 4.0 release candidates, the tvservice command may already be installed. You can check by issuing the following command:

which tvservice

If it is installed, just add the HDMI off command to /etc/rc.local.

# Turn off HDMI
/usr/bin/tvservice -o

If you’re running Pi-Star 3.x, I learned that you can install tvservice from a .deb package.

sudo apt-get install libraspberrypi-bin

For some reason this did not turn up during my initial searches but was pointed out over in the Pi-Star Forums by Dennis (W1MT).

It also seems that Andy (MM0MWZ) is considering adding a button in the future which would allow turning off HDMI from the web interface.

Turn off HDMI on Pi-Star Image

It is common practice on headless Raspberry Pi computers to turn off the HDMI to save some power. Even without a monitor attached, the HDMI hardware seems to draw ~ 50 ma of current. However, in the interest of saving space in the image, Pi-Star (as distributed) lacks the necessary tvservice command to turn off the HDMI hardware.

This command is part of the Raspberry PI “userland” package, which for some reason is not packaged as a .deb. So you’ll have to grab the code off github, but it is pretty easy. Before starting, make certain that you have expanded the filesystem of your image to fill the SD card.

sudo pistar-expand
sudo reboot

After the reboot, do the following:

rpi-rw
git clone https://github.com/raspberrypi/userland
sudo apt-get install cmake -y
cd userland
./buildme

Add the libraries to the ld.so search patch by creating a file named “userland.conf” in /etc/ld.so.conf.d. In that file add the following line:

/opt/vc/lib

Next, update the ld.so search path:

sudo ldconfig -v

You can now run the tvservice command:

## Status
sudo /opt/vc/bin/tvservice -s
## Turn off HDMI
sudo /opt/vc/bin/tvservice -o

All that is left to be done is to add the HDMI off command to your /etc/rc.local file so that it will run every time the system boots.

Will Opaqueness Kill Brandmeister?

In response to the ill-advised Brandmeister ban on the DV4mini devices by Corey Dean (N3FE), I approached some of the key personnel behind the Brandmeister DMR system to determine if I could put up a new master server in the USA. The purpose of the server would be to support the stations requiring extended routing who had been disenfranchised by N3FE.

Most of the Brandmeister core team do not publish email addresses, but I was able to get in touch with Yentel (ON3YH). He indicated that he was not active any more in the development process, but said the he would pass on my message to Artem (R3ABM) and Rudy (PD0ZRY). After a couple of weeks with no further response, I tried some social media channels where I put the following questions to Artem and Rudy:

“Does Brandmeister have a policy which supports the action of the USA Administrators who disabled access to TG 4999 (extended routing)?

“Thousands of USA users who require access to extended routing have been abandoned by the current admins. Therefore, I propose to put up a new master server in the USA which will support those abandoned users by explicitly supporting extended routing. Will you permit/support this?”

Finally Artem came back to me. Not with a straight answer mind you, but a roadblock:

“Please discuss this with Corey Dean”

Talk about opaque. Not a yes, not a no, not a statement of policy. Not an answer on behalf of the core development team as to whether they support the actions of the USA team. Rather, appeal your execution to the executioner and don’t bother me. This is not exactly an answer in keeping with the amateur radio objectives of mentoring and experimentation.

The team running Brandmeister has a published list of policies. Policy number 9 for master server operators is:

“Promote a positive image of BrandMeister”

It seems that the leaders of this project could better comply with their own policies. Their image is not looking too shiny to me right now.

What happens next? What if someone decides that MMDVM boards made in China or Kenwood repeaters or you fill-in-the-blanks are not to their liking and decides to ban them? It is ironic that the Brandmeister project sprang up because of the closed nature of the DMR-MARC C-Bridge networks which preceeded them. The Brandmeister devs were the freedom fighters.

Now, they are the bureaucrats.