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  13  <h1>
  14      <a href="https://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16  </h1>
  17
  18 </div>
  19
  20
  21
  22     <div class="entry">
  23       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Automatic_LinuxCNC_servo_PID_tuning_.html">Automatic LinuxCNC servo PID tuning?</a></div>
  24       <div class="date">16th July 2022</div>
  25       <div class="body"><p>While working on a CNC with servo motors controlled by the
  26 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a>
  27 <a href="https://en.wikipedia.org/wiki/PID_controller">PID
  28 controller</a>, I recently had to learn how to tune the collection of values
  29 that control such mathematical machinery that a PID controller is.  It
  30 proved to be a lot harder than I hoped, and I still have not succeeded
  31 in getting the Z PID controller to successfully defy gravity, nor X
  32 and Y to move accurately and reliably.  But while climbing up this
  33 rather steep learning curve, I discovered that some motor control
  34 systems are able to tune their PID controllers.  I got the impression
  35 from the documentation that LinuxCNC were not.  This proved to be not
  36 true</p>
  37
  38 <p>The LinuxCNC
  39 <a href="http://linuxcnc.org/docs/html/man/man9/pid.9.html">pid
  40 component</a> is the recommended PID controller to use.  It uses eight
  41 constants <tt>Pgain</tt>, <tt>Igain</tt>, <tt>Dgain</tt>,
  42 <tt>bias</tt>, <tt>FF0</tt>, <tt>FF1</tt>, <tt>FF2</tt> and
  43 <tt>FF3</tt> to calculate the output value based on current and wanted
  44 state, and all of these need to have a sensible value for the
  45 controller to behave properly.  Note, there are even more values
  46 involved, theser are just the most important ones.  In my case I need
  47 the X, Y and Z axes to follow the requested path with little error.
  48 This has proved quite a challenge for someone who have never tuned a
  49 PID controller before, but there is at least some help to be found.
  50
  51 <p>I discovered that included in LinuxCNC was this old PID component
  52 at_pid claiming to have auto tuning capabilities.  Sadly it had been
  53 neglected since 2011, and could not be used as a plug in replacement
  54 for the default pid component.  One would have to rewriting the
  55 LinuxCNC HAL setup to test at_pid.  This was rather sad, when I wanted
  56 to quickly test auto tuning to see if it did a better job than me at
  57 figuring out good P, I and D values to use.</p>
  58
  59 <p>I decided to have a look if the situation could be improved.  This
  60 involved trying to understand the code and history of the pid and
  61 at_pid components.  Apparently they had a common ancestor, as code
  62 structure, comments and variable names were quite close to each other.
  63 Sadly this was not reflected in the git history, making it hard to
  64 figure out what really happened.  My guess is that the author of
  65 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/at_pid.c">at_pid.c</a>
  66 took a version of
  67 <a href="https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/pid.c">pid.c</a>,
  68 rewrote it to follow the structure he wished pid.c to have, then added
  69 support for auto tuning and finally got it included into the LinuxCNC
  70 repository.  The restructuring and lack of early history made it
  71 harder to figure out which part of the code were relevant to the auto
  72 tuning, and which part of the code needed to be updated to work the
  73 same way as the current pid.c implementation.  I started by trying to
  74 isolate relevant changes in pid.c, and applying them to at_pid.c.  My
  75 aim was to make sure the at_pid component could replace the pid
  76 component with a simple change in the HAL setup loadrt line, without
  77 having to "rewire" the rest of the HAL configuration.  After a few
  78 hours following this approach, I had learned quite a lot about the
  79 code structure of both components, while concluding I was heading down
  80 the wrong rabbit hole, and should get back to the surface and find a
  81 different path.</p>
  82
  83 <p>For the second attempt, I decided to throw away all the PID control
  84 related part of the original at_pid.c, and instead isolate and lift
  85 the auto tuning part of the code and inject it into a copy of pid.c.
  86 This ensured compatibility with the current pid component, while
  87 adding auto tuning as a run time option.  To make it easier to identify
  88 the relevant parts in the future, I wrapped all the auto tuning code
  89 with '#ifdef AUTO_TUNER'.  The end result behave just like the current
  90 pid component by default, as that part of the code is identical.  The
  91 <a href="https://github.com/LinuxCNC/linuxcnc/pull/1820">end result
  92 entered the LinuxCNC master branch</a> a few days ago.</p>
  93
  94 <p>To enable auto tuning, one need to set a few HAL pins in the PID
  95 component.  The most important ones are <tt>tune-effort</tt>,
  96 <tt>tune-mode</tt> and <tt>tune-start</tt>.  But lets take a step
  97 back, and see what the auto tuning code will do.  I do not know the
  98 mathematical foundation of the at_pid algorithm, but from observation
  99 I can tell that the algorithm will, when enabled, produce a square
 100 wave pattern centered around the <tt>bias</tt> value on the output pin
 101 of the PID controller.  This can be seen using the HAL Scope provided
 102 by LinuxCNC.  In my case, this is translated into voltage (+-10V) sent
 103 to the motor controller, which in turn is translated into motor speed.
 104 So at_pid will ask the motor to move the axis back and forth.  The
 105 number of cycles in the pattern is controlled by the
 106 <tt>tune-cycles</tt> pin, and the extremes of the wave pattern is
 107 controlled by the <tt>tune-effort</tt> pin.  Of course, trying to
 108 change the direction of a physical object instantly (as in going
 109 directly from a positive voltage to the equivalent negative voltage)
 110 do not change velocity instantly, and it take some time for the object
 111 to slow down and move in the opposite direction.  This result in a
 112 more smooth movement wave form, as the axis in question were vibrating
 113 back and forth.  When the axis reached the target speed in the
 114 opposing direction, the auto tuner change direction again.  After
 115 several of these changes, the average time delay between the 'peaks'
 116 and 'valleys' of this movement graph is then used to calculate
 117 proposed values for Pgain, Igain and Dgain, and insert them into the
 118 HAL model to use by the pid controller.  The auto tuned settings are
 119 not great, but htye work a lot better than the values I had been able
 120 to cook up on my own, at least for the horizontal X and Y axis.  But I
 121 had to use very small <tt>tune-effort<tt> values, as my motor
 122 controllers error out if the voltage change too quickly.  I've been
 123 less lucky with the Z axis, which is moving a heavy object up and
 124 down, and seem to confuse the algorithm.  The Z axis movement became a
 125 lot better when I introduced a <tt>bias</tt> value to counter the
 126 gravitational drag, but I will have to work a lot more on the Z axis
 127 PID values.</p>
 128
 129 <p>Armed with this knowledge, it is time to look at how to do the
 130 tuning.  Lets say the HAL configuration in question load the PID
 131 component for X, Y and Z like this:</p>
 132
 133 <blockquote><pre>
 134 loadrt pid names=pid.x,pid.y,pid.z
 135 </pre></blockquote>
 136
 137 <p>Armed with the new and improved at_pid component, the new line will
 138 look like this:</p>
 139
 140 <blockquote><pre>
 141 loadrt at_pid names=pid.x,pid.y,pid.z
 142 </pre></blockquote>
 143
 144 <p>The rest of the HAL setup can stay the same.  This work because the
 145 components are referenced by name.  If the component had used count=3
 146 instead, all use of pid.# had to be changed to at_pid.#.</p>
 147
 148 <p>To start tuning the X axis, move the axis to the middle of its
 149 range, to make sure it do not hit anything when it start moving back
 150 and forth.  Next, set the <tt>tune-effort</tt> to a low number in the
 151 output range.  I used 0.1 as my initial value.  Next, assign 1 to the
 152 <tt>tune-mode</tt> value. Note, this will disable the pid controlling
 153 part and feed 0 to the output pin, which in my case initially caused a
 154 lot of drift.  In my case it proved to be a good idea with X and Y to
 155 tune the motor driver to make sure 0 voltage stopped the motor
 156 rotation.  On the other hand, for the Z axis this proved to be a bad
 157 idea, so it will depend on your setup.  It might help to set the
 158 <tt>bias</tt> value to a output value that reduce or eliminate the
 159 axis drift.  Finally, after setting <tt>tune-mode</tt>, set
 160 <tt>tune-start</tt> to 1 to activate the auto tuning.  If all go well,
 161 your axis will vibrate for a few seconds and when it is done, new
 162 values for Pgain, Igain and Dgain will be active.  To test them,
 163 change <tt>tune-mode</tt> back to 0.  Note that this might cause the
 164 machine to suddenly jerk as it bring the axis back to its commanded
 165 position, which it might have drifted away from during tuning.  To
 166 summarize with some halcmd lines:</p>
 167
 168 <blockquote><pre>
 169 setp pid.x.tune-effort 0.1
 170 setp pid.x.tune-mode 1
 171 setp pid.x.tune-start 1
 172 # wait for the tuning to complete
 173 setp pid.x.tune-mode 0
 174 </pre></blockquote>
 175
 176 <p>After doing this task quite a few times while trying to figure out
 177 how to properly tune the PID controllers on the machine in, I decided
 178 to figure out if this process could be automated, and wrote a script
 179 to do the entire tuning process from power on.  The end result will
 180 ensure the machine is powered on and ready to run, home all axis if it
 181 is not already done, check that the extra tuning pins are available,
 182 move the axis to its mid point, run the auto tuning and re-enable the
 183 pid controller when it is done.  It can be run several times.  Check
 184 out the
 185 <a href="https://github.com/SebKuzminsky/MazakVQC1540/blob/bon-dev/scripts/run-auto-pid-tuner">run-auto-pid-tuner</a>
 186 script on github if you want to learn how it is done.</p>
 187
 188 <p>My hope is that this little adventure can inspire someone who know
 189 more about motor PID controller tuning can implement even better
 190 algorithms for automatic PID tuning in LinuxCNC, making life easier
 191 for both me and all the others that want to use LinuxCNC but lack the
 192 in depth knowledge needed to tune PID controllers well.</p>
 193
 194 <p>As usual, if you use Bitcoin and want to show your support of my
 195 activities, please send Bitcoin donations to my address
 196 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 197 </div>
 198       <div class="tags">
 199
 200
 201         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 202
 203
 204       </div>
 205     </div>
 206     <div class="padding"></div>
 207
 208     <div class="entry">
 209       <div class="title"><a href="https://people.skolelinux.org/pere/blog/My_free_software_activity_of_late__2022_.html">My free software activity of late (2022)</a></div>
 210       <div class="date">20th June 2022</div>
 211       <div class="body"><p>I guess it is time to bring some light on the various free software
 212 and open culture activities and projects I have worked on or been
 213 involved in the last year and a half.</p>
 214
 215 <p>First, lets mention the book
 216 <a href="http://www.hungry.com/~pere/publisher/">releases I managed to
 217 publish</a>.  The Cory Doctorow book "Hvordan knuse
 218 overvåkningskapitalismen" argue that it is not the magic machine
 219 learning of the big technology companies that causes the surveillance
 220 capitalism to thrive, it is the lack of trust busting to enforce
 221 existing anti-monopoly laws.  I also published a family of
 222 dictionaries for machinists, one sorted on the English words, one
 223 sorted on the Norwegian and the last sorted on the North Sámi words.
 224 A bit on the back burner but not forgotten is the Debian
 225 Administrators Handbook, where a new edition is being worked on.  I
 226 have not spent as much time as I want to help bring it to completion,
 227 but hope I will get more spare time to look at it before the end of
 228 the year.</p>
 229
 230 <p>With my Debian had I have spent time on several projects, both
 231 updating existing packages, helping to bring in new packages and
 232 working with upstream projects to try to get them ready to go into
 233 Debian.  The list is rather long, and I will only mention my own
 234 isenkram, openmotor, vlc bittorrent plugin, xprintidle, norwegian
 235 letter style for latex, bs1770gain, and recordmydesktop.  In addition
 236 to these I have sponsored several packages into Debian, like audmes.</p>
 237
 238 <p>The last year I have looked at several infrastructure projects for
 239 collecting meter data and video surveillance recordings.  This include
 240 several ONVIF related tools like onvifviewer and zoneminder as well as
 241 rtl-433, wmbusmeters and rtl-wmbus.</p>
 242
 243 <p>In parallel with this I have looked at fabrication related free
 244 software solutions like pycam and LinuxCNC.  The latter recently
 245 gained improved translation support using po4a and weblate, which was
 246 a harder nut to crack that I had anticipated when I started.</p>
 247
 248 <p>Several hours have been spent translating free software to
 249 Norwegian Bokmål on the Weblate hosted service.  Do not have a
 250 complete list, but you will find my contributions in at least gnucash,
 251 minetest and po4a.</p>
 252
 253 <p>I also spent quite some time on the Norwegian archiving specification
 254 Noark 5, and its companion project Nikita implementing the API
 255 specification for Noark 5.</p>
 256
 257 <p>Recently I have been looking into free software tools to do company
 258 accounting here in Norway., which present an interesting mix between
 259 law, rules, regulations, format specifications and API interfaces.</p>
 260
 261 <p>I guess I should also mention the Norwegian community driven
 262 government interfacing projects Mimes Brønn and Fiksgatami, which have
 263 ended up in a kind of limbo while the future of the projects is being
 264 worked out.</p>
 265
 266 <p>These are just a few of the projects I have been involved it, and
 267 would like to give more visibility.  I'll stop here to avoid delaying
 268 this post.</p>
 269
 270 <p>As usual, if you use Bitcoin and want to show your support of my
 271 activities, please send Bitcoin donations to my address
 272 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 273 </div>
 274       <div class="tags">
 275
 276
 277         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 278
 279
 280       </div>
 281     </div>
 282     <div class="padding"></div>
 283
 284     <div class="entry">
 285       <div class="title"><a href="https://people.skolelinux.org/pere/blog/LinuxCNC_translators_life_just_got_a_bit_easier.html">LinuxCNC translators life just got a bit easier</a></div>
 286       <div class="date"> 3rd June 2022</div>
 287       <div class="body"><p>Back in oktober last year, when I started looking at the
 288 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a> system, I
 289 proposed to change the documentation build system make life easier for
 290 translators.  The original system consisted of independently written
 291 documentation files for each language, with no automated way to track
 292 changes done in other translations and no help for the translators to
 293 know how much was left to translated.  By using
 294 <a href="https://po4a.org/">the po4a system</a> to generate POT and PO
 295 files from the English documentation, this can be improved.  A small
 296 team of LinuxCNC contributors got together and today our labour
 297 finally payed off.  Since a few hours ago, it is now possible to
 298 translate <a href="https://hosted.weblate.org/projects/linuxcnc/">the
 299 LinuxCNC documentation on Weblate</a>, alongside the program itself.</p>
 300
 301 <p>The effort to migrate the documentation to use po4a has been both
 302 slow and frustrating.  I am very happy we finally made it.</p>
 303
 304 <p>As usual, if you use Bitcoin and want to show your support of my
 305 activities, please send Bitcoin donations to my address
 306 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 307 </div>
 308       <div class="tags">
 309
 310
 311         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 312
 313
 314       </div>
 315     </div>
 316     <div class="padding"></div>
 317
 318     <div class="entry">
 319       <div class="title"><a href="https://people.skolelinux.org/pere/blog/geteltorito_make_CD_firmware_upgrades_a_breeze.html">geteltorito make CD firmware upgrades a breeze</a></div>
 320       <div class="date">20th April 2022</div>
 321       <div class="body"><p>Recently I wanted to upgrade the firmware of my thinkpad, and
 322 located the firmware download page from Lenovo (which annoyingly do
 323 not allow access via Tor, forcing me to hand them more personal
 324 information that I would like).  The
 325 <a href="https://support.lenovo.com/no/en/search?query=thinkpad firmware bios upgrade iso&SearchType=Customer search&searchLocation=Masthead">download
 326 from Lenovo</a> is a bootable ISO image, which is a bit of a problem
 327 when all I got available is a USB memory stick.  I tried booting the
 328 ISO as a USB stick, but this did not work.  But genisoimage came to
 329 the rescue.</p>
 330
 331 <P>The geteltorito program in
 332 <a href="http://tracker.debian.org/cdrkit">the genisoimage binary
 333 package</a> is able to convert the bootable ISO image to a bootable
 334 USB stick using a simple command line recipe, which I then can write
 335 to the most recently inserted USB stick:</p>
 336
 337 <blockquote><pre>
 338 geteltorito -o usbstick.img lenovo-firmware.iso
 339 sudo dd bs=10M if=usbstick.img of=$(ls -tr /dev/sd?|tail -1)
 340 </pre></blockquote>
 341
 342 <p>This USB stick booted the firmware upgrader just fine, and in a few
 343 minutes my machine had the latest and greatest BIOS firmware in place.</p>
 344 </div>
 345       <div class="tags">
 346
 347
 348         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 349
 350
 351       </div>
 352     </div>
 353     <div class="padding"></div>
 354
 355     <div class="entry">
 356       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Playing_and_encoding_AV1_in_Debian_Bullseye.html">Playing and encoding AV1 in Debian Bullseye</a></div>
 357       <div class="date">16th April 2022</div>
 358       <div class="body"><p>Inspired by the recent news of
 359 <a href="https://slashdot.org/story/22/04/03/2039219/intel-beats-amd-and-nvidia-with-arc-gpus-full-av1-support">AV1
 360 hardware encoding support from Intel</a>, I decided to look into
 361 the state of AV1 on Linux today.  AV1 is a
 362 <a href="https://web.archive.org/web/20160618103850/http://www.digistan.org/open-standard:definition">free
 363 and open standard</a> as defined by Digistan without any royalty
 364 payment requirement, unlike its much used competitor encoding
 365 H.264.  While looking, I came across an 5 year
 366 <a href="https://askubuntu.com/questions/1061908/how-to-encode-and-playback-video-with-the-av1-codec-on-bionic-beaver-18-04">old
 367 question on askubuntu.com</a> which in turn inspired me to check out
 368 how things are in Debian Stable regarding AV1.  The test file listed
 369 in the question (askubuntu_test_aom.mp4) did not exist any more, so I
 370 tracked down a different set of test files on
 371 <a href="https://av1.webmfiles.org/">av1.webmfiles.org</a> to test them
 372 with the various video tools I had installed on my machine.  I was
 373 happy to discover that AV1 decoding and playback worked with almost
 374 every tool I tested:
 375
 376 <table align="center">
 377 <tr><td>mediainfo</td>       <td>ok</td></tr>
 378 <tr><td>dragonplayer</td>    <td>ok</td></tr>
 379 <tr><td>ffmpeg / ffplay</td> <td>ok</td></tr>
 380 <tr><td>gnome-mplayer</td>   <td>fail</td></tr>
 381 <tr><td>mplayer</td>         <td>ok</td></tr>
 382 <tr><td>mpv</td>             <td>ok</td></tr>
 383 <tr><td>parole</td>          <td>ok</td></tr>
 384 <tr><td>vlc</td>             <td>ok</td></tr>
 385 <tr><td>firefox</td>         <td>ok</td></tr>
 386 <tr><td>chromium</td>        <td>ok</td></tr>
 387 </table>
 388
 389 <p>AV1 encoding is available in Debian Stable from the aom-tools
 390 version 1.0.0.errata1-3 package, using the aomenc tool.  The encoding
 391 using the package in Debian Stable is quite slow, with the frame rate
 392 for my 10 second test video at around 0.25 fps.  My 10 second video
 393 test took 16 minutes and 11 seconds on my test machine.</p>
 394
 395 <p>I tested by first running ffmpeg and then aomenc using the recipe
 396 provided by the askubuntu recipe above.  I had to remove the
 397 '--row-mt=1' option, as it was not supported in my 1.0.0 version.  The
 398 encoding only used a single thread, according to <tt>top</tt>.</p>
 399
 400 <blockquote><pre>
 401 ffmpeg -i some-old-video.ogv -t 10 -pix_fmt yuv420p video.y4m
 402 aomenc --fps=24/1 -u 0 --codec=av1 --target-bitrate=1000 \
 403   --lag-in-frames=25 --auto-alt-ref=1 -t 24 --cpu-used=8 \
 404   --tile-columns=2 --tile-rows=2 -o output.webm video.y4m
 405 </pre></blockquote>
 406
 407 <p>As version 1.0.0 currently have several
 408 <a href="https://security-tracker.debian.org/tracker/source-package/aom">unsolved
 409 security issues in Debian Stable</a>, and to see if the recent
 410 backport <a href="https://tracker.debian.org/pkg/aom">provided in
 411 Debian</a> is any quicker, I ran <tt>apt -t bullseye-backports install
 412 aom-tools</tt> to fetch the backported version and re-encoded the
 413 video using the latest version.  This time the '--row-mt=1' option
 414 worked, and the encoding was done in 46 seconds with a frame rate of
 415 around 5.22 fps.  This time it seem to be using all my four cores to
 416 encode.  Encoding speed is still too low for streaming and real time,
 417 which would require frame rates above 25 fps, but might be good enough
 418 for offline encoding.</p>
 419
 420 <p>I am very happy to see AV1 playback working so well with the
 421 default tools in Debian Stable.  I hope the encoding situation improve
 422 too, allowing even a slow old computer like my 10 year old laptop to
 423 be used for encoding.</p>
 424
 425 <p>As usual, if you use Bitcoin and want to show your support of my
 426 activities, please send Bitcoin donations to my address
 427 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 428 </div>
 429       <div class="tags">
 430
 431
 432         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/standard">standard</a>, <a href="https://people.skolelinux.org/pere/blog/tags/video">video</a>.
 433
 434
 435       </div>
 436     </div>
 437     <div class="padding"></div>
 438
 439     <div class="entry">
 440       <div class="title"><a href="https://people.skolelinux.org/pere/blog/F__en_slutt_p__Digitale_utslipp.html">Få en slutt på Digitale utslipp</a></div>
 441       <div class="date">14th March 2022</div>
 442       <div class="body"><p>På onsdag sendte jeg følgende epost til Utdanningsetaten i Oslo
 443 kommune (UDE).  Fikk beskjed om at min henvendelse har saksnummer
 444 22/7559-1 i den
 445 <a href="https://www.oslo.kommune.no/etater-foretak-og-ombud/utdanningsetaten/postjournal-utdanningsetaten/">offentlige
 446 postjournalen til UDE</a>.  Jeg er spent på hva slags respons jeg får.
 447 Mistenker jo de fleste som sprer sine nettsideleseres
 448 personopplysninger til utlandet ikke har tenkt så nøye igjennom hva de
 449 gjør, og at det er håp om at de tenker seg litt nøyere om hvis de blir
 450 klar over problemstillingen.  Vet du noen som burde få tilsvarede
 451 beskjed og spørsmål?  Kanskje du kan sende dem en epost.  Hvis alle
 452 bidrar blir det kanskje litt bedre.</p>
 453
 454 <blockquote>
 455 <p>To: postmottak (at) osloskolen.no
 456 <br>Subject: Digitale utslipp fra osloskolens nettsider</p>
 457
 458 <p>Hei.</p>
 459
 460 <p>Jeg ser at osloskolens nettsider har digitale utslipp av
 461 personopplysninger til Google, Facebook og andre, blant annet omtalt
 462 på &lt;URL: <a href="https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/">https://aktuelt.osloskolen.no/personvernerklaring-for-osloskolen/informasjonskapsler/</a>
 463 >.</p>
 464
 465 <p>&lt;URL: <a href="https://webbkoll.dataskydd.net/">https://webbkoll.dataskydd.net/</a> > kan være et nyttig verktøy for å holde øye med utslippsomfanget på ulike sider.</p>
 466
 467 <p>Kanskje det er en ide å gjøre noe med det, jamfør &lt;URL: <a href="https://www.digi.no/artikler/debatt-det-enkleste-tiltaket-er-a-skru-av-google-analytics/517378">https://www.digi.no/artikler/debatt-det-enkleste-tiltaket-er-a-skru-av-google-analytics/517378</a> >?</p>
 468
 469 <p>Et alternativ til Google Analytics kan være en lokalt installert
 470 utgave av &lt;URL:
 471 <a href="https://matomo.org/">https://matomo.org/</a> >.  Den og flere
 472 andre alternativer kan finnes via
 473 &lt;URL: <a href="https://www.digi.no/artikler/sverige-vil-skrote-amerikansk-skytjeneste-her-er-alternativene/516223?key=5QsV0wRG">https://www.digi.no/artikler/sverige-vil-skrote-amerikansk-skytjeneste-her-er-alternativene/516223?key=5QsV0wRG</a> >
 474 på bakgrunn av at svenske myndigheter har innsett at dagens praksis
 475 nok er både lite lur og ulovlig.  Der henger Norge litt etter, men
 476 osloskolen har her mulighet til å være litt i forkant. :)</p>
 477
 478 <p>Fint om dere kan gi beskjed hvilket saksnummer denne henvendelsen får i
 479 offentlig postjournal når den er mottatt.</p>
 480
 481 </blockquote>
 482
 483 </p>Flere og flere innser at slik spredning av personopplysninger er
 484 ugreit.  Det har pågått i mange år.  Ser jeg blogget
 485 <a href="https://people.skolelinux.org/pere/blog/Det_er_jo_makta_som_er_mest_s_rbar_ved_massiv_overv_kning_av_Internett.html">første
 486 gang om Google Analytics i 2013</a> og
 487 <a href="https://people.skolelinux.org/pere/blog/Snurpenot_overv_kning_av_sensitiv_personinformasjon.html">analyserte
 488 omfanget i 2015</a>, men det er et langt lerret å bleke.</p>
 489
 490 <p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til
 491 det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner
 492 til min adresse
 493 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.
 494 Merk, betaling med bitcoin er ikke anonymt. :)</p>
 495 </div>
 496       <div class="tags">
 497
 498
 499         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="https://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 500
 501
 502       </div>
 503     </div>
 504     <div class="padding"></div>
 505
 506     <div class="entry">
 507       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Publish_Hargassner_wood_chip_boiler_state_to_MQTT.html">Publish Hargassner wood chip boiler state to MQTT</a></div>
 508       <div class="date">12th March 2022</div>
 509       <div class="body"><p>Recently I had a look at a
 510 <a href="https://www.hargassner.at/">Hargassner</a>
 511 <a href="https://www.hargassner.at/en/products/wood-chip-boiler.html">wood
 512 chip boiler</a>, and what kind of free software can be used to monitor
 513 and control it.  The boiler can be connected to some cloud service via
 514 what the producer call an Internet Gateway, which seem to be a
 515 computer connecting to the boiler and passing the information gathered
 516 to the cloud.  I discovered the boiler controller got an IP address on
 517 the local network and listen on TCP port 23 to provide status
 518 information as a text line of numbers.  It also provide a HTTP server
 519 listening on port 80, but I have not yet figured out what it can do
 520 beside return an error code.</p>
 521
 522 <p>If I am to believe various free software implementations talking to
 523 such boiler, the interpretation of the line of numbers differ between
 524 type of boiler and software version on the boiler.  By comparing the
 525 list of numbers on the front panel of the boiler with the numbers
 526 returned via TCP, I have been able to figure out several of the
 527 numbers, but there are a lot left to understand.  I've located several
 528 temperature measurements and hours running values, as well as oxygen
 529 measurements and counters.</p>
 530
 531 I decided to write a simple parser in Python for the values I figured
 532 out so far, and a simple MQTT injector publishing both the interpreted
 533 and the unknown values on a MQTT bus to make collecting and graphing
 534 simpler.  The end result is available from the
 535 <a href="https://gitlab.com/petterreinholdtsen/hargassner2mqtt">hargassner2mqtt
 536 project page</a> on gitlab.  I very much welcome patches extending the
 537 parser to understand more values, boiler types and software versions.
 538 I do not really expect very few free software developers got their
 539 hands on such unit to experiment, but it would be fun if others too find
 540 this project useful.</p>
 541
 542 <p>As usual, if you use Bitcoin and want to show your support of my
 543 activities, please send Bitcoin donations to my address
 544 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 545 </div>
 546       <div class="tags">
 547
 548
 549         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>.
 550
 551
 552       </div>
 553     </div>
 554     <div class="padding"></div>
 555
 556     <div class="entry">
 557       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Run_your_industrial_metal_working_machine_using_Debian_.html">Run your industrial metal working machine using Debian?</a></div>
 558       <div class="date"> 2nd March 2022</div>
 559       <div class="body"><p>After many months of hard work by the good people involved in
 560 <a href="https://en.wikipedia.org/wiki/LinuxCNC">LinuxCNC</a>, the
 561 system was accepted Sunday
 562 <a href="https://tracker.debian.org/pkg/linuxcnc">into Debian</a>.
 563 Once it was available from Debian, I was surprised to discover from
 564 <a href="https://qa.debian.org/popcon.php?package=linuxcnc">its
 565 popularity-contest numbers</a> that people have been reporting its use
 566 since 2012.  <a href="http://linuxcnc.org/">Its project site</a> might
 567 be a good place to check out, but sadly is not working when visiting
 568 via Tor.</p>
 569
 570 <p>But what is LinuxCNC, you are probably wondering?  Perhaps a
 571 Wikipedia quote is in place?</p>
 572
 573 <blockquote>
 574 "LinuxCNC is a software system for numerical control of
 575 machines such as milling machines, lathes, plasma cutters, routers,
 576 cutting machines, robots and hexapods. It can control up to 9 axes or
 577 joints of a CNC machine using G-code (RS-274NGC) as input. It has
 578 several GUIs suited to specific kinds of usage (touch screen,
 579 interactive development)."
 580 </blockquote>
 581
 582 <p>It can even control 3D printers.  And even though the Wikipedia
 583 page indicate that it can only work with hard real time kernel
 584 features, it can also work with the user space soft real time features
 585 provided by the Debian kernel.
 586 <a href="https://github.com/linuxcnc/linuxcnc">The source code</a> is
 587 available from Github.  The last few months I've been involved in the
 588 translation setup for the program and documentation.  Translators are
 589 most welcome to
 590 <a href="https://hosted.weblate.org/engage/linuxcnc/">join the
 591 effort</a> using Weblate.</p>
 592
 593 <p>As usual, if you use Bitcoin and want to show your support of my
 594 activities, please send Bitcoin donations to my address
 595 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 596 </div>
 597       <div class="tags">
 598
 599
 600         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="https://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/robot">robot</a>.
 601
 602
 603       </div>
 604     </div>
 605     <div class="padding"></div>
 606
 607     <div class="entry">
 608       <div class="title"><a href="https://people.skolelinux.org/pere/blog/Updated_vlc_bittorrent_plugin_in_Debian__version_2_14_.html">Updated vlc bittorrent plugin in Debian (version 2.14)</a></div>
 609       <div class="date">14th February 2022</div>
 610       <div class="body"><p>I am very happy to report that a new version of the
 611 <a href="https://tracker.debian.org/pkg/vlc-plugin-bittorrent">VLC
 612 bittorrent plugin</a> was just uploaded into debian.  The changes
 613 since last time is mostly code clean in the download code. The package
 614 is currently in Debian unstable, but should be available in Debian
 615 testing son.  To test it, simply install it like this:</p>
 616
 617 <p><pre>
 618 apt install vlc-plugin-bittorrent
 619 </pre></p>
 620
 621 <p>After it is installed, you can try to use it to play a file
 622 downloaded live via bittorrent like this:
 623
 624 <p><pre>
 625 vlc https://archive.org/download/Glass_201703/Glass_201703_archive.torrent
 626 </pre></p>
 627
 628 <p>It can also use magnet links and local .torrent files like the ones
 629 provided by the Internet Archive.  Another example is the <a
 630 href="https://archive.org/details/LoveNest">Love Nest</a> Buster
 631 Keaton movie, where one can click on the 'Torrent' link to get going.</p>
 632
 633 <p>As usual, if you use Bitcoin and want to show your support of my
 634 activities, please send Bitcoin donations to my address
 635 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 636 </div>
 637       <div class="tags">
 638
 639
 640         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/verkidetfri">verkidetfri</a>, <a href="https://people.skolelinux.org/pere/blog/tags/video">video</a>.
 641
 642
 643       </div>
 644     </div>
 645     <div class="padding"></div>
 646
 647     <div class="entry">
 648       <div class="title"><a href="https://people.skolelinux.org/pere/blog/A_Brazilian_Portuguese_translation_of_the_book_Made_with_Creative_Commons.html">A Brazilian Portuguese translation of the book Made with Creative Commons</a></div>
 649       <div class="date"> 3rd December 2021</div>
 650       <div class="body"><p>A few days ago, a productive translator started working on a new
 651 translation of <a href="https://madewith.cc">the Made with Creative
 652 Commons book</a> for Brazilian Portuguese.  The translation take place on
 653 <a href="https://hosted.weblate.org/projects/madewithcc/translation/">the
 654 Weblate web based translation system</a>.  Once the translation is
 655 complete and proof read, we can publish it on paper as well as in PDF,
 656 ePub and HTML format.  The translation is already 16% complete, and if
 657 more people get involved I am conviced it can very quickly reach 100%.
 658 If you are interested in helping out with this or other translations
 659 of the Made with Creative Commons book, start translating on
 660 Weblate.  There are partial translations available in Azerbaijani,
 661 Bengali, Brazilian Portuguese, Dutch, French, German, Greek, Polish,
 662 Simplified Chinese, Swedish, Thai and Ukrainian.</p>
 663
 664 <p>The <a href="https://gitlab.com/gunnarwolf/madewithcc-es.git">git
 665 repository for the book</a> contain all source files needed to build
 666 the book for yourself.
 667 <a href="https://gunnarwolf.gitlab.io/madewithcc-es/">HTML editions</a>
 668 to help with proof reading is also available.</p>
 669
 670 <p>As usual, if you use Bitcoin and want to show your support of my
 671 activities, please send Bitcoin donations to my address
 672 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 673 </div>
 674       <div class="tags">
 675
 676
 677         Tags: <a href="https://people.skolelinux.org/pere/blog/tags/docbook">docbook</a>, <a href="https://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="https://people.skolelinux.org/pere/blog/tags/madewithcc">madewithcc</a>.
 678
 679
 680       </div>
 681     </div>
 682     <div class="padding"></div>
 683
 684     <p style="text-align: right;"><a href="index.rss"><img src="https://people.skolelinux.org/pere/blog/xml.gif" alt="RSS feed" width="36" height="14" /></a></p>
 685     <div id="sidebar">
 686
 687
 688
 689 <h2>Archive</h2>
 690 <ul>
 691
 692 <li>2022
 693 <ul>
 694
 695 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/02/">February (1)</a></li>
 696
 697 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/03/">March (3)</a></li>
 698
 699 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/04/">April (2)</a></li>
 700
 701 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/06/">June (2)</a></li>
 702
 703 <li><a href="https://people.skolelinux.org/pere/blog/archive/2022/07/">July (1)</a></li>
 704
 705 </ul></li>
 706
 707 <li>2021
 708 <ul>
 709
 710 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/01/">January (2)</a></li>
 711
 712 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/02/">February (1)</a></li>
 713
 714 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/05/">May (1)</a></li>
 715
 716 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/06/">June (1)</a></li>
 717
 718 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/07/">July (3)</a></li>
 719
 720 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/08/">August (1)</a></li>
 721
 722 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/09/">September (1)</a></li>
 723
 724 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/10/">October (1)</a></li>
 725
 726 <li><a href="https://people.skolelinux.org/pere/blog/archive/2021/12/">December (1)</a></li>
 727
 728 </ul></li>
 729
 730 <li>2020
 731 <ul>
 732
 733 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/02/">February (2)</a></li>
 734
 735 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/03/">March (2)</a></li>
 736
 737 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/04/">April (2)</a></li>
 738
 739 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/05/">May (3)</a></li>
 740
 741 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/06/">June (2)</a></li>
 742
 743 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/07/">July (1)</a></li>
 744
 745 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/09/">September (1)</a></li>
 746
 747 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/10/">October (1)</a></li>
 748
 749 <li><a href="https://people.skolelinux.org/pere/blog/archive/2020/11/">November (1)</a></li>
 750
 751 </ul></li>
 752
 753 <li>2019
 754 <ul>
 755
 756 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/01/">January (4)</a></li>
 757
 758 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/02/">February (3)</a></li>
 759
 760 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/03/">March (3)</a></li>
 761
 762 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/05/">May (2)</a></li>
 763
 764 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/06/">June (5)</a></li>
 765
 766 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/07/">July (2)</a></li>
 767
 768 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/08/">August (1)</a></li>
 769
 770 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/09/">September (1)</a></li>
 771
 772 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/11/">November (1)</a></li>
 773
 774 <li><a href="https://people.skolelinux.org/pere/blog/archive/2019/12/">December (4)</a></li>
 775
 776 </ul></li>
 777
 778 <li>2018
 779 <ul>
 780
 781 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/01/">January (1)</a></li>
 782
 783 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/02/">February (5)</a></li>
 784
 785 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/03/">March (5)</a></li>
 786
 787 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/04/">April (3)</a></li>
 788
 789 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/06/">June (2)</a></li>
 790
 791 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/07/">July (5)</a></li>
 792
 793 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/08/">August (3)</a></li>
 794
 795 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/09/">September (3)</a></li>
 796
 797 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/10/">October (5)</a></li>
 798
 799 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/11/">November (2)</a></li>
 800
 801 <li><a href="https://people.skolelinux.org/pere/blog/archive/2018/12/">December (4)</a></li>
 802
 803 </ul></li>
 804
 805 <li>2017
 806 <ul>
 807
 808 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
 809
 810 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
 811
 812 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
 813
 814 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
 815
 816 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
 817
 818 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
 819
 820 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
 821
 822 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
 823
 824 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/10/">October (5)</a></li>
 825
 826 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/11/">November (3)</a></li>
 827
 828 <li><a href="https://people.skolelinux.org/pere/blog/archive/2017/12/">December (4)</a></li>
 829
 830 </ul></li>
 831
 832 <li>2016
 833 <ul>
 834
 835 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
 836
 837 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
 838
 839 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
 840
 841 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
 842
 843 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
 844
 845 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
 846
 847 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
 848
 849 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
 850
 851 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
 852
 853 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
 854
 855 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
 856
 857 <li><a href="https://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
 858
 859 </ul></li>
 860
 861 <li>2015
 862 <ul>
 863
 864 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
 865
 866 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
 867
 868 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
 869
 870 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
 871
 872 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
 873
 874 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
 875
 876 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
 877
 878 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
 879
 880 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
 881
 882 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
 883
 884 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
 885
 886 <li><a href="https://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
 887
 888 </ul></li>
 889
 890 <li>2014
 891 <ul>
 892
 893 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 894
 895 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 896
 897 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 898
 899 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 900
 901 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 902
 903 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 904
 905 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 906
 907 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 908
 909 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
 910
 911 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
 912
 913 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
 914
 915 <li><a href="https://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
 916
 917 </ul></li>
 918
 919 <li>2013
 920 <ul>
 921
 922 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 923
 924 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 925
 926 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 927
 928 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 929
 930 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 931
 932 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 933
 934 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 935
 936 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 937
 938 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 939
 940 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 941
 942 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 943
 944 <li><a href="https://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 945
 946 </ul></li>
 947
 948 <li>2012
 949 <ul>
 950
 951 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 952
 953 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 954
 955 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 956
 957 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 958
 959 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 960
 961 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 962
 963 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 964
 965 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 966
 967 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 968
 969 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 970
 971 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 972
 973 <li><a href="https://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 974
 975 </ul></li>
 976
 977 <li>2011
 978 <ul>
 979
 980 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 981
 982 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 983
 984 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 985
 986 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 987
 988 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 989
 990 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 991
 992 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 993
 994 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 995
 996 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 997
 998 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 999
1000 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1001
1002 <li><a href="https://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1003
1004 </ul></li>
1005
1006 <li>2010
1007 <ul>
1008
1009 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1010
1011 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1012
1013 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1014
1015 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1016
1017 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1018
1019 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1020
1021 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1022
1023 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1024
1025 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1026
1027 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1028
1029 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1030
1031 <li><a href="https://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1032
1033 </ul></li>
1034
1035 <li>2009
1036 <ul>
1037
1038 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1039
1040 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1041
1042 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1043
1044 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1045
1046 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1047
1048 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1049
1050 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1051
1052 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1053
1054 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1055
1056 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1057
1058 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1059
1060 <li><a href="https://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1061
1062 </ul></li>
1063
1064 <li>2008
1065 <ul>
1066
1067 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1068
1069 <li><a href="https://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1070
1071 </ul></li>
1072
1073 </ul>
1074
1075
1076
1077 <h2>Tags</h2>
1078 <ul>
1079
1080  <li><a href="https://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (19)</a></li>
1081
1082  <li><a href="https://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1083
1084  <li><a href="https://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1085
1086  <li><a href="https://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1087
1088  <li><a href="https://people.skolelinux.org/pere/blog/tags/betalkontant">betalkontant (9)</a></li>
1089
1090  <li><a href="https://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (12)</a></li>
1091
1092  <li><a href="https://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (17)</a></li>
1093
1094  <li><a href="https://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1095
1096  <li><a href="https://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1097
1098  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian">debian (181)</a></li>
1099
1100  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (159)</a></li>
1101
1102  <li><a href="https://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (8)</a></li>
1103
1104  <li><a href="https://people.skolelinux.org/pere/blog/tags/digistan">digistan (11)</a></li>
1105
1106  <li><a href="https://people.skolelinux.org/pere/blog/tags/dld">dld (18)</a></li>
1107
1108  <li><a href="https://people.skolelinux.org/pere/blog/tags/docbook">docbook (30)</a></li>
1109
1110  <li><a href="https://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1111
1112  <li><a href="https://people.skolelinux.org/pere/blog/tags/english">english (437)</a></li>
1113
1114  <li><a href="https://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
1115
1116  <li><a href="https://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (14)</a></li>
1117
1118  <li><a href="https://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (34)</a></li>
1119
1120  <li><a href="https://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
1121
1122  <li><a href="https://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (20)</a></li>
1123
1124  <li><a href="https://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
1125
1126  <li><a href="https://people.skolelinux.org/pere/blog/tags/intervju">intervju (43)</a></li>
1127
1128  <li><a href="https://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (16)</a></li>
1129
1130  <li><a href="https://people.skolelinux.org/pere/blog/tags/kart">kart (23)</a></li>
1131
1132  <li><a href="https://people.skolelinux.org/pere/blog/tags/kodi">kodi (4)</a></li>
1133
1134  <li><a href="https://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1135
1136  <li><a href="https://people.skolelinux.org/pere/blog/tags/lego">lego (5)</a></li>
1137
1138  <li><a href="https://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
1139
1140  <li><a href="https://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
1141
1142  <li><a href="https://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1143
1144  <li><a href="https://people.skolelinux.org/pere/blog/tags/madewithcc">madewithcc (3)</a></li>
1145
1146  <li><a href="https://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1147
1148  <li><a href="https://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (42)</a></li>
1149
1150  <li><a href="https://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (13)</a></li>
1151
1152  <li><a href="https://people.skolelinux.org/pere/blog/tags/noark5">noark5 (23)</a></li>
1153
1154  <li><a href="https://people.skolelinux.org/pere/blog/tags/norsk">norsk (320)</a></li>
1155
1156  <li><a href="https://people.skolelinux.org/pere/blog/tags/nuug">nuug (198)</a></li>
1157
1158  <li><a href="https://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (40)</a></li>
1159
1160  <li><a href="https://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1161
1162  <li><a href="https://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (75)</a></li>
1163
1164  <li><a href="https://people.skolelinux.org/pere/blog/tags/personvern">personvern (114)</a></li>
1165
1166  <li><a href="https://people.skolelinux.org/pere/blog/tags/raid">raid (2)</a></li>
1167
1168  <li><a href="https://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1169
1170  <li><a href="https://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1171
1172  <li><a href="https://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
1173
1174  <li><a href="https://people.skolelinux.org/pere/blog/tags/robot">robot (16)</a></li>
1175
1176  <li><a href="https://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1177
1178  <li><a href="https://people.skolelinux.org/pere/blog/tags/ruter">ruter (7)</a></li>
1179
1180  <li><a href="https://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1181
1182  <li><a href="https://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (59)</a></li>
1183
1184  <li><a href="https://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1185
1186  <li><a href="https://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
1187
1188  <li><a href="https://people.skolelinux.org/pere/blog/tags/standard">standard (72)</a></li>
1189
1190  <li><a href="https://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (7)</a></li>
1191
1192  <li><a href="https://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (14)</a></li>
1193
1194  <li><a href="https://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (62)</a></li>
1195
1196  <li><a href="https://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (5)</a></li>
1197
1198  <li><a href="https://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
1199
1200  <li><a href="https://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
1201
1202  <li><a href="https://people.skolelinux.org/pere/blog/tags/verkidetfri">verkidetfri (20)</a></li>
1203
1204  <li><a href="https://people.skolelinux.org/pere/blog/tags/video">video (77)</a></li>
1205
1206  <li><a href="https://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1207
1208  <li><a href="https://people.skolelinux.org/pere/blog/tags/web">web (42)</a></li>
1209
1210 </ul>
1211
1212
1213     </div>
1214     <p style="text-align: right">
1215  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1216 </p>
1217
1218   </body>
1219 </html>