Xmas Lights - Continued 2022

 This year I had plans to use the ESPCAM board to expand my lights, but after much messing about and the distraction of a couple of other non-lighting  projects I could not get the ESPIXELSTICK software to work reliably in a stable configuration as a FPP remote.  I ended up at last minute swapping it out for a 4 port falcon remote.

My matrix as not happy about the amount of rain this year, and I had a number of pixels that suffered as a result, although once I got into a situation that I could climb up and replace them they had dried out and were working again. (5v bullet pixels) - need to consider in next screen build if running the string horizontally may reduce the water running down the wires and into the back of the pixels?

Interestingly the much maligned in the lights community LED strip is still working strongly after a number of years, and seems to generally survive much better in the weather as long as you don't put strain on it (mine is all cable ties to conduit)

After setting up a couple of strings of LED seed pixels for a mate using a ESP8266 and WLED, I decided to look at WLED on the ESPCAM boards.  Interestingly it works fine for the bullet pixels and the LED strip I have but with the seed pixels I get the first LED being predominantly white and a lot of flicker, have not yet worked out how to solve that so it is still on the list.   Using WLED as and FPP remote is still listed on the future features list - SDCARD support is working if you turn on the user extension, the ability to play an fseq file does not seem to be too far away.

Todo
- assess matrix
- investigate seed pixels behavior
- monitor progress on espixelstick and wled firmware.

Flash ESP32-CAM with espixelstick 4beta4

 Downloaded firmware from https://github.com/forkineye/ESPixelStick/releases.

Unzipped folder

Connected up the ESP32-CAM (not the one that came with the MB) using the MB
(the ESP32-CAM variant that came with the MB plugged straight in and programmed)

The orange jumper puts it in programming mode

java -jar ESPSFlashTool.jar

Set configuration options for wifi/hostname and board type

Upload

when the first stage completes and it says that it did a hard reset - press the reset button on the esp board and the second stage will progress (it will fail if you don't press reset)

Remove the jumper

When the programming is complete press reset and it should boot into the software. (give it some time to set up)

Next I need to work out how to turn off the bright flash LED as it is blinding.

Pixel Controllers - ESP32-CAM

 After finding some interesting open source controller layouts by Scott Hanson (https://github.com/computergeek1507) I decided to get a couple of boards made by jcbpcb and have a go at some improved controllers.

After looking through the various controller layouts I settled on one based on the ESP32-CAM board, commonly available at a good price on aliexpress.  It seems to hit a sweet spot of being about to insert an sdcard, upload sequences from xlights and have it act as a FPP Remote, while giving 4 outputs for lights.  The only thing missing is ethernet, but at the same time I am looking for something at a lower price point than the big controllers.

The next step was to purchase the components to make up the board.  Mostly straight forward but the ESP32-CAM boards became interesting after making up the first board and starting on programming an configuration.

I ran into an issue where the first board I programmed would not boot when installed in the controller board, after some debugging with jumper wires  I found that if I didn't connect one of the GND pins it booted and ran.

After a bit more playing I decided to program up another ESP32, and this one would not program using the ESP32-CAM-MB, I eventually found a work around and got it programmed.  When inserted in the controller it ran without a problem - this is when I started to look closer at the boards as their behaviour was different.

ESP32-CAM-MB (only a RST switch)

ESP32-CAM - purchased with MB

ESP32-CAM - purchased separately from same supplier

If you look closely at the two ESP32-CAM boards you may notice the pin on the top left has a different label on each board - one is GND/R and the other GND.   It appears that they have linked this pin on the board that came with the MB to the RST pin of the ESP, therefore linking it to GND causes it to constantly reset and not boot.  The other visible difference is that the column of tiny resistors near that pin has 6 components, rather than 4 on the other board.

I have also had an issue with the SDcard in the board with the reset - still need to investigate that at some point, but at the moment I am continuing to build the first controller to determine if there are any other changes I need to make. 

The nice thing about making your own controllers is you do not need to buy components that add no value for your application, such as a voltage regulator for those powering it with 12v, as I am using 5v and plugs for the outputs when I can just attach the pigtails I want to use to the board.

2021 Christmas Lights

The lights have grown, the controllers are now a Falcon F16v3 (love the Falcon, but high cost is limiting) and two esp8266 home brew controllers running Espixelstick firmware.  The show is in it own vlan, run from a Raspberry Pi running fpp.  All sequencing is done in xlights.

I am about to embark on a new phase of the christmas lights with plans to expand, improve the configuration to reduce maintenance of props and controllers.

A couple of examples of current setup are on youtube

Christmas Lights - Part 2

So the bits started to arrive, early on were the first order of WS2812B LED Strip and a 5v power supply.  So I started looking for a way to test them.

These strips had 3 wires - 5v, Ground and Data.  I needed to find a way to send data, and then it hit me - Arduino - so out of the stash I dragged and Arduino Uno.  Found some examples of how to drive the pixels with the FastLED library.  As it had been a while since last using arduino this to a little bit of effort to remember all the steps, but I got a proof of concept up and running.

Next we needed to think about mounting the LED strips on the house.  After a bit of research on auschristmaslighting.com I found that a recommended method was to cable tie the strips to conduit and then mount hte conduit on the house.  This filled in a couple of days buying/measuring/cutting and mounting it on the house.  Then taking the conduit down to mount the lights on the conduit.  Care needs to be taken to not over-tighten the cable ties as you do not want to damage the strip, also you should resist the urge to pull the strip tight along the length of the conduit as this can cause failure.
(the reading I have done since buying strip would indicate that it is less robust than strings of LED and a number of people have had many failures)

During this process I also learned to shorten strips of led and also join strings of LED.  With care you can join it pad to pad like it is from factory.

With all the LED strips joined (total of 600 LEDS) the limitations of the Uno memory with FastLED became apparent.  I flashed the code the an Arduino Mega and this problem was eliminated for now.

During this process the DMX SPI decoders arrived.  So it was time to have a play, the end result was that until I could find time to work with sequencing software and true control of the lights this was a simple answer to drive the lights when they first got up on the house.

The reading continued looking at controllers and software....

Christmas Lights - Part 1

Well like a lot of people in the past I have put up a few lights on the house during December, having shifted from a house that had no street frontage this became something I could do.  I have not done this for about 7 years. So the result is a number of strings of lights of various types (incandescent and led), strings, icicles etc that all are driven from wall warts.

A couple of years ago I saw my first sequenced light show on a local house, the idea of computer control, music synchronization etc appealed to me.  I went home did a number in internet searches, realised the cost involved and then parked the idea.

2017 - found the 101 Lighting Manual on https://auschristmaslighting.com/  did some reading.  Great document but still really hard going.

Leap forward to 2018 the 11.11 sale on aliexpress and the lower prices of rgb led strips.  Then the research started properly.  It quickly became apparent that the only way I was going to get anywhere was to buy a few samples products and have a play.

• 4x 5meters DC5V 30LED/M WS2812b led strip 30IC/M SMD5050 led, IP67 waterproof
• 5v 40A LED power supply
• USB to DMX Interface
• DMX decoder 30 channels RGB LED strip lights driver DMX 512 Dimmer no Plastic Box DC 9V-24V

Anybody that knows anything about the above will know that this is a completely useless combination of parts to do anything, I was heading in two different directions at the same time.  As I read more in the evening I came to this conclusion, as a result one day later the next purchase was.

• 5M 300Led waterproof RGB led strip light 5050 DC12V 60Leds/M
  (to use with the DMX items above)
• DC5V ws2812B rgb controller decoder board ic led strip LED SPI Converter
  (to use with the LED strips in the first purchase)

Research continued....

OCR on Fedora Linux

I just had a problem that I have not dealt with for many years, as most documents I can get quite easily in a soft copy.  The problem occurred as I was provided with a print out of a document that I have to include in a newsletter, and I do not have time to track down the email of the author.  As a result I decided to look for an OCR solution for fedora.

Of course there are a number of packages available in the standard repositories, after reading some reviews on the net I decided to try tesseract, as although it is quite choosy about the input format it generally does a high accuracy job.

yum install tesseract

I used my brother MFC-7420 to scan the document using simple scan in fedora.  The default setting I had were 150dpi for text.

I saved the file as PNG(lossless) and then used gimp to convert it to tiff.

tesseract test.png test

The result was a file test.txt - not the best conversion - a lot of errors where things like 'in' had become 'rn'.  Clearly this was because the letters were running into each other a bit.

I then re-scanned the document at 600 dpi, gimp convert to tiff and tesseract again.  WOW - what a difference.  Apart from a few issues with spacing (not a problem as I need to re-format all files to suit scribus anyway) it has just saved me quite a time typing.

Yeah, another open source package that works!

References:
http://www.dedoimedo.com/computers/linux-ocr.html
http://www.mscs.dal.ca/~selinger/ocr-test/

Take time to learn Linux/Unix

Warning personal rant follows.

Over the years I have used a number of different flavours of Unix/Linux.  Unix flavour I have used include AIX (IBM), SunOS/Solaris (Was Sun, now Oracle), IRIX (SGI), HPUX (HP), Ultrix (DEC).  Linux flavours include Suse, Mandrake, Mandriva, Redhat, Fedora, DSL, Puppy and many more.

When I first started with AIX, I had come from the world of the Apple Macintosh that was all nice a fluffy - you did most things point and click (except for development).  The shock was large, I had to write some shell scripts and some C programs.  vi was the most unpleasant piece of crap I had ever seen.  So I took a couple of days out and compiled emacs on the AIX machine.  For the next year or so was happy in the world of emacs.

That was of course until a machine had a major issue and I needed to start it in maintenance mode.  Then you get a scaled back OS to fix the machine with, and you guessed it vi was the editor.

Over time I then had to administer other machines with other versions of Unix, some of these had emacs, but all had vi.  It suddenly dawned on me I need to take the time to learn vi.  From that point forward I have never looked back, I would struggle now to drive emacs.

The thing that has become clear to me in the world of computer administration is take the time to learn all the standard tools and the standard ways to do things  - if you rely of having a customised environment you will spend a lot of time  building the custom environment each time you have a new machine to look after, rather than getting on with the job at hand. 

The world is different if your job is that of programmer and you spend all your time on one computer, customise your environment on the machine, to minimise the amount of time doing all the other activities that do not involve writing code.

I expect all aspiring linux/unix sysadmins to learn vi, sed, awk, shell scripting and even perl.  The mark of a true sysadmin is when the GUI starts the first application they run is a terminal to get to the command line, and this is where they spend most their time.  Otherwise you are just a hobbyist (there is nothing wrong with having a hobby), and the title System Administrator becomes devalued.

Also take the time to learn as many tools and technologies as you can.  Each one you learn makes you more valuable to the world of IT, gives you more depth and once you move to jobs where you are given the task to architect a system you have a better understanding of more tools.  Too many systems are built using the wrong tools just because they are the only ones people know.

After Update, FC15 does not start correctly

From time to time there are various problems after an update that result in the machine not getting all the way to the GUI prompt after an update.  With a little bit of knowledge this becomes a less concerning issue, and can be quite easily fixed.

My most recent experiences of this were a few weeks ago, I ran a yum update - there was a new kernel package installed, but the graphics drivers from rpmfusion had not been released for the kernel.  As a result the machine appear to hang during boot at the point when it should have started X11.

To help with these issues, the first thing I do when I install linux is edit the grub.conf file and change the timeout parameter from 0 to 3.  This puts a 3 second pause in the startup, that allows you to press a key and get a boot menu up, that allows you to select an older kernel to boot.  (You can also change the command line it uses to start the kernel).  When you then have these problems you can simply use this menu to boot the previous kernel.

Even without this, you can switch to another terminal session on your console with CTRL-ALT-F2  (F3, F4...)  CTRL-ALT-F1 will get you back.  You can then log in and get a command line.

When things get really bad you will need to get out you linux install media and boot off that, to get a command line to perform the recovery.

No matter how you do it, once you have a command line you can fix your install.

Most often you can fix it by changing the default boot kernel to the previous one.  Edit the /etc/grub.conf file - the line to edit the default=0,  this is a reference to the first OS entry in the file, to boot using the second one change it to default=1.

Another technique is to use yum to roll back the changes, as described in yum - help I have broken my install

Another thing to consider if you are taking a lot of updates and often have problmes is to change the number of kernels that are allowed to be installed at one time.  This is done in the /etc/yum.conf file, you can change the line installonly_limit=3 to a higher number.  I usually set mine to 5 just to have a bit more buffer when things start to go wrong.

One of the realities of linux is that it is more stable a reliable on slightly older hardware that the drivers have had the bugs ironed out in them.  When you are in the situation I have been lately where some of the hardware I have is only just supported in the latest release then this is when stability issues come to the fore.

yum - help I have broken my install

Yes it happens from time to time - you do a yum update to get the latest packages for the fedora distribution or you install a new package which breaks your system.  The good news is that there is a record kept of what you have installed/updated.
You can look at the yum.log in /var/log/ which will show you what packages have been updated/erased with yum.

You can also use the yum history command to see what has been happening

yum history

Loaded plugins: langpacks, presto, refresh-packagekit
ID     | Login user               | Date and time    | Action(s)      | Altered
-------------------------------------------------------------------------------
   138 |  <fred>                  | 2011-07-24 11:24 | Update         |   25 EE
   137 | root <root>              | 2011-07-24 11:08 | Downgrade      |   21 EE
   136 | root <root>              | 2011-07-24 11:04 | Downgrade      |    4  
   135 | root <root>              | 2011-07-24 10:36 | Update         |    4  
   134 |  <fred>                  | 2011-07-23 13:25 | Update         |   55 EE
   133 |  <fred>                  | 2011-07-17 12:00 | I, U           |   71  
   132 |  <fred>                  | 2011-07-10 15:06 | Install        |    1  
   131 |  <fred>                  | 2011-07-10 15:06 | Install        |    1  
   130 |  <fred>                  | 2011-07-10 15:06 | Install        |    2  

You can then use yum history undo <number> to rollback any update.
You can see that step 136 and 137 are a result of this - I uninstalled the previous two upgrades when trying to debug a startup issue


Other handy commands

yum history info <nnn>
yum history redo <nnn>

Fedora Core 15 - Install - Continued

I have been experiencing a number of stability issues with FC15.  Mostly to do with it not booting cleanly or firefox crashing frequently.  But also with the most recent kernel updates the machine came up with a garbled screen.  Today I have had a chance to have a closer look at it and work out what is wrong.

Firstly I noticed I am getting a number of errors from the nouveau drivers for the nvidia card I have so I decided to load kmod-nvidia from the rpmfusion repository.

I installed this, now hardware acceleration is functioning correctly and I am seeing the new gnome interface in its full glory.  Proceeded to read some online documentation about this and found firefox is now crashing with increased frequency.

Had a look and /var/log/messages and each time it was crashing it was logging a message :

 dbus-daemon: [system] Activation via systemd failed for unit 'dbus-org.freedesktop.NetworkManager.service': Unit dbus-org.freedesktop.NetworkManager.service failed to load: No such file or directory. See system logs and 'systemctl status' for details.

Given that I had previously attempted to disable network manager this was a bit of a puzzle to me.  After a bit of playing about with systemctl I decided to remove Network Manager with yum erase.

It appear that now firefox is much more stable.

To get the shutdown command back in FC15 I installed
gnome-shell-extensions-alternative-status-menu

And to make a few more tweaks to the interface I installed
gnome-tweak-tool

Hopefully this will give me a more stable system.

Fedora Core 15 - Install

My FC14 started to act up, and FC15 is out, so I took the plunge and decided to install FC15.

I am a believer in fresh installs of the OS, rather than upgrades :-

1. You can retain the old install (disk) intact if you have problems you can go back to it.
2. You get rid of any rubbish that may have been hanging about, that can have an impact on the reliability of the new install.

Backup your data.

I isolated the FC14 disk by removing the cable - this is to ensure, I get the right disk for the install and I get a boot loader on the disk I am installing to, otherwise I have suddenly become dependent on both disks, and I have not retained my FC14.

I did a vanilla install of FC15 x86_64  - then plugged back in the FC14 disk.

Once rebooted after install logged in

yum update

vi /etc/grub.conf 

removed rhgb and added timeout of 3 (so I get a menu if I have problems with a kernel and I can see what is happening during boot)



Changed the configuration from Network-Manager to network to get networking working at boot - edited /etc/sysconfig/network-scripts/ifcfg-eth0 to achive the settings I desired.

yum install of

• system-config-displaymanager
• system-config-displaymanager-gnome
• gconf-editor
• qcad
• scribus
• system-config-lvm

configures rpmfusion.org, rpm.livna.org

yum install of

• vlc 
• devede 
• inkscape 
• thunderbird 
• thunderbird-lightning 
• pitivi 
• agave
• fuse-encfs

vgchange -ay to activate the FC14 lvm partitions
mount /dev/mapper/<vgfilesystem> /mnt/home
copied the /home contents to new install
copied additional user information from /etc/passwd /etc/shadow /etc/group

edit /etc/selinux/config - change settings for selinux to preferred options

Set up printers - got brother drivers from brother website
Problems with brother driver crashing from qcad was traced to requiring a2ps - once this was installed it all worked.


Over time I will get the settings refined to what I desire - but now I have notes of the process I took I can refer to them when I do the FC16 upgrade.  I suggest you try to keep notes of your build, even if it is just the packages you add as it saves a lot of time trying to figure out "What was that DVD burning software I was using?"  e.t.c.

AirPrint for iPad and FC14

I bought a new toy - an iPad 2.

Great toy - having a lot of fun with a device with a good size screen, but portable.  Slowly working out the apps that I require to make it useful.

The other day I thought I should look into printing, and started reading about AirPrint and then I saw the list of AirPrint printers that are supported, the official list only had HP devices, although I have since heard that a number of brother devices also support AirPrint.

After looking around on the web, I found a number of references to setting up a linux machine as an Airprint Server.

Using http://www.micromux.com/2010/11/22/airprint-for-mac-on-linux/ and http://lists.fedoraproject.org/pipermail/users/2010-November/387560.html
I started to configure it.

To my surprise it took about 15 minutes, and I can print from my iPad through CUPS on Fedora 14 and out comes a print on my Brother MFC-7420.

I have managed to print images from the photo app, and also anything that I can view in Safari, so it does not seem to have the limitations that Steve found when he posted his information.  So you don't have to race out and buy a new printer, unless of course you want a new printer.

I have now done the same with Fedora 15 -  so simple

1. Add ServerAlias * to the /etc/cups/cupsd.conf file
2. Download airprint-generate.py from https://github.com/tjfontaine/airprint-generate
3. Run airprint-generate.py
4. Copy resulting files to/etc/avahi/services
5. Restart cups and  avahi-daemon

2018 - update on airprint

Time to get a new printer, need colour, did some research and price checks, remembered my views on brands just before purchase and go an HP Color LaserJet Pro MFP M281dfw
wifi, airprint....  printing from MacOS, IOS, Windows all works great.
 

Skype - Fedora 14

I have just installed Skype 2.1 Beta 2 on Fedora 14 x86_64.

To get it to work I had to install the following 32 bit packages -

yum install libX11.i686
yum install libv4l.i686
yum install alsa-plugins-pulseaudio.i686
yum install qt.i686
yum install libXScrnSaver.i686
yum install libXv.i686
yum install libQtGTL.i686

You can check the objects you need using ldd to show you all the libraries you are missing.

# ldd /usr/bin/skype
 linux-gate.so.1 =>  (0xf7798000)
 libasound.so.2 => /lib/libasound.so.2 (0xf7686000)
 libXv.so.1 => /usr/lib/libXv.so.1 (0xf7681000)
 libXss.so.1 => /usr/lib/libXss.so.1 (0xf767e000)
 librt.so.1 => /lib/librt.so.1 (0x46c69000)
 libQtDBus.so.4 => /usr/lib/libQtDBus.so.4 (0xf7605000)
 libQtGui.so.4 => /usr/lib/libQtGui.so.4 (0xf6b77000)
 libQtNetwork.so.4 => /usr/lib/libQtNetwork.so.4 (0xf6a60000)
 libQtCore.so.4 => /usr/lib/libQtCore.so.4 (0xf67cc000)
 libpthread.so.0 => /lib/libpthread.so.0 (0x46c38000)
 libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0xf66df000)
 libm.so.6 => /lib/libm.so.6 (0x46df7000)
 libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x46ffc000)
 libc.so.6 => /lib/libc.so.6 (0x46aac000)
 libdl.so.2 => /lib/libdl.so.2 (0x46c55000)
 libX11.so.6 => /usr/lib/libX11.so.6 (0x4709e000)
 libXext.so.6 => /usr/lib/libXext.so.6 (0x472c2000)
 /lib/ld-linux.so.2 (0x46a8b000)
        ... 

yum - Yellowdog Updater Modified

The difficult part is finding which packages the libraries that are missing are in.

The best tool to learn to use for managing rpm packages on Fedora is yum.
yum install <packages>  will install the package and all the dependencies get installed too (after prompting you with the total list)

You can find the package that provides a file with a command such as

yum provides libX11.so.6 

If you want to update the packages on your system to the lastest for your version of Fedora then

yum update

If You just want to list them then

yum check-update

The power of yum is great and I use it in preference to the PackageKit widget in Gnome as it gives me the control of when and what I download to my machine.

VirtualBox - a great way to keep your old PC image

I have an old Windows XP machine that the motherboard has failed on.  It has a lot of data and programs on it that I use from time to time (it was my primary PC for 6 years).  I have found that Oracle VirtualBox (from their purchase of Sun) can be very helpful in allowing me to have an image of my old machine running on my new machine as I transition.  This has greatly reduced the pain of loosing the old machine.

I put the XP disk in a USB carrier and plugged it into my Linux machine.  Using command like

cat /dev/sdg | VBoxManage convertfromraw stdin OutPutFile.vdi NUMBEROFBYTES

I managed to image the disk to a file on the linux machine. I then started VirtualBox and created a virtual machine using the disk image.

On startup the machine blue screened, just like windows does from time to time. Not to worry, I got my original XP CD and told virtualbox it was in the cd drive. Then on booting the virtual machine I did a windows repair. Windows now booted and after a couple of windows updates I have my machine back in a virtual environment.

A couple of things I found along the way -

The VirtualBox that is distributed with Linux is the Open Source Edition and does not have the extensions to use USB - download the executable from http://www.virtualbox.org - They even have a fedora repo file so you can keep it up to date with yum.

Follow the instructions on getting the kernel extensions built - you will have to do this each time you update you linux kernel.

I had problems where after installing the VirtualBox extensions I could not get shared folders to work, it kept saying they do not appear to be installed. It turns out the Kaspersky Internet Security was blocking the install - disable it and try again, magically the install works. After doing this and rebooting it is working fine.

Squid Proxy

Given my main home machine is now running Fedora 14 rather than windows I have decided to install the squid proxy to have a look at how this can help with caching web pages locally.

The install was very straight foward

yum install squid
vi /etc/squid/squid.conf

I then uncommented the squid_dir line in the file to allow it to write a disk cache and started the proxy with

service squid start

Then configured the browser (firefox) to use the squid proxy on the default port 3128.

Thats it.

To look at the contents of the squid logs I installed calamaris

yum install calamaris

cd /var/log/squid

cat access.log | calamaris -a | more

Further steps I will look at is allowing access from other machines on my home network - likely I will have to adjust the iptables firewall to allow them to connect, but this is something you should take the time to understand if you don't already.   (you can always use the GUI tools to configure these things, but that does not help me long term when administering machines through terminal sessions, so I like to use the command line where possible)

Welcome

Well this is the start of the ramblings of an IT professional that fills in his spare time turning wood.  The main point of this blog is for me to store notes for myself about the attempt to use OpenSource software as much as possible and the tools I have found that help.  There may also be a bit of woodturning sneak in for a peek from time to time.

I am a huge fan of Linux based systems, as my first jobs it IT were using AIX, Solaris and IRiX my experience of various Unix derivatives is extensive.  Linux has presented a path where we can us commodity hardware and have a stable reliable server platform without the degree of investment that was required 20 year ago.

My Linux flavour of choice currently is Fedora for the cutting edge and Redhat Enterprise for the stable backend services.  When it comes to commercial software on a Linux platform you are normally looking at full support on either Redhat of SuSe, and it just makes life easier if you work with a consistent platform rather than changing every time you install a new system.