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A while ago we bought new Pulse 15 laptops from Tuxedo Computers.

Installed Ubuntu on them, and for a while the sleep mode was nagging me, it does not really work. Today I found time to investigate this issue.

First let's find out which sleep mode is enabled:

cat /sys/power/mem_sleep
[s2idle]

Something is wrong here. Not only can't I set the sleep mode to the desired "deep" mode, the "deep" mode is not even available. That explains why things are not working as expected.

After some research it turns out that this might be a BIOS problem. Prepare to reboot!

After the laptop powers up, press the "Del" key until the BIOS comes up. Then navigate to "Advanced Settings" -> "AMD PBS" -> "S3/Modern Standby Support".

The default is "Modern Standby Enable", but it turns out that this is the culprit. Changing this to "S3 Enable" and then reboot fixes the problem and "deep" now shows up in the available Linux Power States.

Then follow the description in this link, and permamently set the sleep mode to "deep".

cat /sys/power/mem_sleep
s2idle [deep]

Sometimes I have to extract Exif information from images, mostly the GPS coordinates. The coordinates coming raw from the images are not very helpful. Let's look at a picture I took today:

Bowl of ice cream

darktable shows the following coordinates:

latitude: N 52° 40,198'
longitude: E 013° 16,852'
elevation: 93,90 m above sea level

Now that is not very helpful, because neither OpenStreetMap nor Google recognize this format out of the box:

N 52° 40,198' E 013° 16,852'

Coordinates not working in OpenStreetMap

Coordinates not working in Google

Bummer. And I don't have the time or energy to fix that every time I need the coordinates. Luckily exiftool can output the coordinates in different formats, which is super helpful. For my use cases I choose the Degrees.MinutesSeconds format, also named "Decimal degrees", or DD. This format shows latitude and longitude geographic coordinates as decimal fractions of a degree.

exiftool -time:all -location:all -G -a -s -c "%.6f"

The explanation for the options used here:

• -G: Print group name for each tag
• -a: Allow duplicate tags to be extracted
• -s: Short output format
• -v: Print verbose messages
• -q: Quiet processing
• -c "%.6f": Set format for GPS coordinates

Using these settings, I get the following coordinates:

[Composite]     GPSAltitude                     : 93.9 m Above Sea Level
[Composite]     GPSLatitude                     : 52.669959 N
[Composite]     GPSLongitude                    : 13.280862 E
[Composite]     GPSPosition                     : 52.669959 N, 13.280862 E

Which sure enough brings me right to the ice cream place "Il Pistacchio" in Hohen Neuendorf, which I visited earlier today.

Il Pistacchio on OpenStreetMap

From time to time our laptops receive firmware updates, by using the Linux Vendor Firmware Service (short: fwupd). This worked fine for a long time, until it didn't. One day I was facing the following error message:

root@laptop:/root# fwupdmgr update

╔══════════════════════════════════════════════════════════════════════════════╗
║ Upgrade Embedded Controller from 0.1.23 to 0.1.25?                           ║
╠══════════════════════════════════════════════════════════════════════════════╣
║                                                                              ║
║ ...                                                                          ║
║                                                                              ║
╚══════════════════════════════════════════════════════════════════════════════╝

Perform operation? [Y|n]: 
Downloading…             [***************************************]
Decompressing…           [***************************************]
Authenticating…          [***************************************]
Waiting…                 [***************************************]
Waiting…                 [***************************************]
/usr/libexec/fwupd/efi/fwupdx64.efi and /usr/libexec/fwupd/efi/fwupdx64.efi.signed cannot be found

During the first few occasions I basically ignored the error message, and attributed it to a glitch in a software package. Maybe a later update will fix this.

But this never happened, so I looked into the issue.

Ubuntu split the 1.6.x version of fwupd into separate packages, and does not install the packages fwupd-signed and fwupd-unsigned to deal with EFI binaries.

apt-get install -y fwupd-signed fwupd-unsigned

Now everything is working again:

root@laptop:/root# fwupdmgr update
╔══════════════════════════════════════════════════════════════════════════════╗
║ Upgrade Embedded Controller from 0.1.23 to 0.1.25?                           ║
╠══════════════════════════════════════════════════════════════════════════════╣
║                                                                              ║
║ ...                                                                          ║
║                                                                              ║
╚══════════════════════════════════════════════════════════════════════════════╝

Perform operation? [Y|n]: 
Downloading…             [***************************************]
Downloading…             [***************************************]
Decompressing…           [***************************************]
Authenticating…          [***************************************]
Waiting…                 [***************************************]
Writing…                 [***************************************]
Waiting…                 [***************************************]
Successfully installed firmware
Do not turn off your computer or remove the AC adapter while the update is in progress.
Waiting…                 [***************************************]

Voila! Also updated the playbook which installs the laptops, to include the two new packages.

If you use GitHub Actions to run Workflows and tests, you might have spotted this warning recently:

Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: actions/checkout@v2

This warning means that GitHub will deprecate a certain action, which checks out the repository into the runner. This is going on since early 2022 and by summer 2023 they plan to upgrade all actions to v16.

If you use GitHub Actions to run Workflows and tests, you might have spotted this warning recently:

The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

This warning means that GitHub will deprecate a certain syntax which populates variables, and disables it by end of May 2023.

It was time to update my laptop, and I already knew that the update will bring Snap, and installs the Snap Firefox version. Along with many known problems. Previously the laptop was on 20.04 LTS, but this version is about to loose support.

I ran through the upgrade, and then added an Ansible Playbook to handle the Firefox installation, remove the Snap version and install the PPA version. Most of my laptop configuration is handled using Ansible Playbooks.

One of the things I do in our network is public drives. Every Linux system has a public "incoming" which is mapped to the primary user of the device (if there is one, like for a laptop). And this incoming shared drive can be accessed without password.

This makes it really convenient to copy files around from one laptop/user to another, or from mobile devices to laptops and vice versa, or use the printer/scanner to send the scan job directly to the laptop of the user's device. All in all, the users like this, and use it a lot. There is also minimal protection built-in, it will only work in our home network, access is blocked when the laptop is connected to a different network. But the folders are mostly empty anyway. For sharing files over the Internet we also have a Syncthing instance running, but that's a different story, and not as easy to use.

One thing which I was annoyed about is that by default a Mac will try to connect as a registered user. There is an option "Connect as Guest", but it's not pre-selected. Therefore every time I wanted to share something between Linux and Mac, I had to start "Finder", to to "Go" and then "Connect to Server", then click on the server from the list of last entries, and then also click on "Guest". The built-in help is also not useful, as it only talks about "click on Guest".

But it turns out that one can "pre-select" the Guest user. For this, the username is "Guest", and there is no password. This goes between the protocol and the hostname. Example:

smb://192.168.0.20/incoming

becomes:

smb://Guest:@192.168.0.20/incoming

There has to be a ":" between the username and the (non-existent) password, and the credentials are separated from the hostname by a "@". Using this connect string will auto-connect as anonymous user to the remote share. One click and a couple seconds saved!

The Huginn software is not only good for monitoring Twitter feeds, it can also be used to monitor websites for changes.

That's actually easy and needs only two agents:

• Website Agent
• Notification Agent - Email Agent, maybe

openHAB can integrate Google Calendars. The functionality is kind of limited, it can only see the current and the next calendar event, but in my case that is enough. More about the use case in another blog post.

There are three different calendar bindings available, let's have a quick look:

• CalDAV Personal Binding: this is a v1 binding, which means it will no longer work in the soon-to-be-released openHAB v3. Apparently this works with Google calendars, but has performance issues. It can show the current and next event.
• Google Calendar Scheduler: also a v1 binding. Needs more work for presense simulation, and additional bindings.
• iCalendar Binding: v2 binding, should work with v3. It can show the current and next event. That's the one I'm going to use.

A very common use case for hooks in git is a "pre-commit" hook. This hook is used to verify the to-be-committed data before it is added to the repository.

One important note: hooks are not part of the repository itself. Everyone can install a hook on it's own checkout of a repository, but by default the hook is not there when you clone/checkout the repository. This avoids security problems by executing arbitrary code during "git commit", or any "git" operation.
Because of this implication it is common that developers install a hook from somewhere in the repository into the ".git/hooks" directory. And in addition, the server side (the repository) can run the same checks during "git push", to enforce the rules.

Hooks in git work in a simple way: whatever program or script is run as the hook has to set a return code. If the return code is "0", git proceeds. If it's not "0", git aborts the operation.

In my ongoing endeavor to improve our home, a while ago I added a notification when the washing machine and the dryer are finished. The notification is send to a Telegram channel. Over the summer vacation I added a number new ChromeCast Audio devices (Google no longer offers the Audio CC, if you need one get one now). One is placed in the kitchen. Not only can I listen to music while eating breakfast, I can also output notifications, by using the CC as an audio sink in openHAB.

To make that useful, I decided to use a Text-to-Speech system. openHAB offers a couple different TTS systems, however most of them need a cloud integration, and therefore a working Internet connection. The "Pico TTS" works standalone, and was my favorite choice for this implementation.

In my previous blog post about "Tankerkönig" I explained the details of how to integrate this binding into openHAB and provide a Telegram interface.

Someone on the openHAB community forum pointed out that Telegram bots allow queries, where one can present the user with options, and the user only has to click on one of the options. That makes it easier to use, and less typing is required as well. I went ahead and implemented that.

My plan is to reinstall openHABian on a bigger SDcard, and on a Raspberry Pi 4. The latest release (v1.5) supports the new Pi 4, and I decided it's time to do a fresh install, and see if all my Playbooks are still working.

Raspberry Pi 4 with Sectronics Armor (cooling) Case

As always, I'm searching my shell history for the right command how to install the image ... but came up empty.

By default, openHAB only starts 5 threads to deal with execution of Rules. That's not a lot, and if all threads are busy, rules have to wait until a slot is free. This results in slow Rule response time.

This can be improved.

After figuring out if a ChromeCast is currently used, it was time to fix a long-standing problem. At home we don't have TVs, just "dumb" displays, and stream content using ChromeCasts. However a video ChromeCast never really turns off, but keeps the display running, using a "Backdrop" app. This app keeps showing pictures on the display when the ChromeCast is not used otherwise, effectively preventing any powersafe mode.

That's both annoying (who wants to have pictures shown in the living room or working room all night), and consumes energy. It's also intentional by Google. So far we had to turn the display on and off manually, which is inconvenient.