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Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

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Archive for the ‘Hardware Development’ Category

NeonHorizon/lipopi: Guide to setting up LiPo batteries on the Raspberry Pi

Posted by jpluimers on 2017/04/12

Interesting hardware project: NeonHorizon/lipopi: Guide to setting up LiPo batteries on the Raspberry Pi

Pictures: Daniel Bull – Google+

Basically it’s a mini-UPS that works for any Raspberry Pi, but for a model 3 you have to add a tiny capacitor.

From the readme:

  • Description: LiPoPi is a guide to setting up the Raspberry Pi with a LiPo battery including both running and charging it
  • Project Website: GitHub
  • Requirements: A Raspberry Pi (any model – see notes about the Raspbery Pi 3) and an Adafruit PowerBoost 500 Charger or 1000C Charger
  • Skillset: Requires soldering skills and a basic knowledge of the command line
  • License: GPL Version 3

–jeroen

Read the rest of this entry »

Posted in Development, Hardware Development, Raspberry Pi | Leave a Comment »

Having one Raspberry Pi reset another Raspberry Pi through relay or transistor

Posted by jpluimers on 2017/04/11

I’m going to build this later, but as the follow up on shortening the RUN pins of a Raspberry Pi to reset it in The woods and trees of OpenSuSE on single-board computers – image abbreviations – and getting it installed using OS X, I want to see if the below will work for me to have a pair (maybe trio?) of Raspberry Pi devices watch each other and reset any hung one.

The need comes because sometimes a Raspberry Pi either hangs or just won’t finish a reboot sequence:

Basically a Raspberry Pi has GPIO pins that can drive electromechanic (like mechanical relay) or electronic (like transistor+resistors or SSR solid-state relay). Examples:

So basic steps:

  1. Get switching gear (relay+diode, transistor+resistors or solid-state-relay)
  2. On each Pi modify the RUN holes so it has a header
  3. Connect header to switching gear
  4. Write watch-dog code to monitor other Pi and flip GPIO pin
  5. Test, test, test

And since I’m relatively new at electronics:

–jeroen

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Posted in *nix, Development, Hardware Development, Linux, openSuSE, Power User, Raspberry Pi, SuSE Linux | Leave a Comment »

127.0.1.1 in /etc/hosts for your hostname?

Posted by jpluimers on 2017/04/07

Coming from an OpenSuSE background, I was a bit surprised to find 127.0.1.1 in the /etc/hosts file to point to the hostname in Raspbian distributions.

It means you have to change at least these files when altering the hostname:

/etc/hosts
/etc/hostname

In addition to those, I also changed these:

/etc/ssh/ssh_host_rsa_key.pub
/etc/ssh/ssh_host_ecdsa_key.pub
/etc/ssh/ssh_host_dsa_key.pub
/etc/ssh/ssh_host_ed25519_key.pub
/etc/.git/description

After altering these files, you want to run this (via: Pi Town: Change a Raspberry Pi’s Hostname without Rebooting [WayBack])

sudo /etc/init.d/hostname.sh start

This prevents In order to prevent messages like sudo: unable to resolve host raspberrypi without rebooting.

The 127.0.0.1 seems to be a Debian thing: Chapter 5. Network setup – 5.1.1. The hostname resolution [WayBack] has

The IP address 127.0.1.1 in the second line of this example may not be found on some other Unix-like systems. The Debian Installer creates this entry for a system without a permanent IP address as a workaround for some software (e.g., GNOME) as documented in the bug #719621.

The <host_name> matches the hostname defined in the “/etc/hostname“.

For a system with a permanent IP address, that permanent IP address should be used here instead of 127.0.1.1.

For a system with a permanent IP address and a fully qualified domain name (FQDN) provided by the Domain Name System (DNS), that canonical <host_name>.<domain_name> should be used instead of just <host_name>.

via: linux – Why does my hostname appear with the address 127.0.1.1 rather than 127.0.0.1 in /etc/hosts? – Server Fault [WayBack]

There isn’t a great deal of difference between the two; 127/8 (eg: 127.0.0.0 => 127.255.255.255) are all bound to the loopback interface.

The reason why is documented in the Debian manual here:http://www.debian.org/doc/manuals/debian-reference/ch05.en.html#_the_hostname_resolution

Ultimately, it is a bug workaround; the original report is here: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=316099

–jeroen

Posted in *nix, Development, Hardware Development, Linux, openSuSE, Power User, Raspberry Pi, SuSE Linux | Leave a Comment »

OpenSuSE Tumbleweed on Raspberry Pi: getting `vcgencmd version` to work to see which GPU firmware you have

Posted by jpluimers on 2017/04/05

When you search for raspberry pi firmware version check

Installing and running rpi-update will – besides updating the GPU firmware – also install vcgencmd, I got this result:

statler:~ # LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/vc/lib/
statler:~ # export LD_LIBRARY_PATH
statler:~ # /opt/vc/bin/vcgencmd version
Jul 15 2016 17:50:10 
Copyright (c) 2012 Broadcom
version efa728fef77ea14ceb1500caf0146395fa282a0f (clean) (release)

But I wanted to be able to run vcgencmd before installing updates.

openmamba indicates it’s part of their raspberrypi-utils package with sources in the raspberrypi-userland package tracing back to git://github.com/raspberrypi/userland.git which is at https://github.com/raspberrypi/userland.

So I had two choices: compile https://github.com/raspberrypi/userland or find the binaries that rpi-update installs and are already runnable. I went for the second first by digging in https://github.com/Hexxeh/rpi-update/blob/master/rpi-update which on one of the first lines points to https://github.com/Hexxeh/rpi-firmware where the binaries are stored under https://github.com/Hexxeh/rpi-firmware/tree/master/vc/softfp/opt/vc.

The logic for copying the files is in the update_vc_libs function. The calling do_update function updates a lot more, including the firmware. So I wrote a quick pull request to just download the userland binaries:

Feature SKIP_FIRMWARE for #220: forces SKIP_KERNEL=1 and also skip the kernel.img files and the kernel modules: This effectively only installs the userland and SDK.

Source: #220 feature `SKIP_FIRMWARE` by jpluimers · Pull Request #221 · Hexxeh/rpi-update

Hopefully it gets merged in. When not, then you can always take a look at the commit: #220 feature SKIP_FIRMWARE · jpluimers/rpi-update@5a2ec0b

Run these commands to get going:

cd /root/bin
wget https://raw.githubusercontent.com/jpluimers/rpi-update/5a2ec0bc552436d58127cc20e3791cb5b90fd5ba/rpi-update
chmod +x rpi-update
SKIP_FIRMWARE=1 UPDATE_SELF=0 ./rpi-update

You should see this when updating:

 *** Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS and Dom
 *** We're running for the first time
 *** Backing up files (this will take a few minutes)
 *** Remove old firmware backup
 *** As requested, not updating firmware and kernel modules
This update bumps to rpi-4.4.y linux tree
Be aware there could be compatibility issues with some drivers
Discussion here:
https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=144087
##############################################################
 *** Downloading specific firmware revision (this will take a few minutes)
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   168    0   168    0     0    361      0 --:--:-- --:--:-- --:--:--   362
100 51.2M  100 51.2M    0     0  1246k      0  0:00:42  0:00:42 --:--:-- 1446k
 *** As requested, not updating firmware and kernel
 *** As requested, not updating firmware and kernel modules
 *** Updating VideoCore libraries
 *** Using HardFP libraries
 *** Updating SDK
 *** Running ldconfig
 *** Storing current firmware revision
 *** Deleting downloaded files
 *** Syncing changes to disk
 *** If no errors appeared, your firmware was successfully updated to 818a860cf690d64c62d3227ad9c36d5867a671c2
 *** A reboot is needed to activate the new firmware

And the final goal of checking the firmware version now works:

# LD_LIBRARY_PATH=/opt/vc/lib /opt/vc/bin/vcgencmd version
Jul 15 2016 17:50:10 
Copyright (c) 2012 Broadcom
version efa728fef77ea14ceb1500caf0146395fa282a0f (clean) (release)

–jeroen

Posted in Development, Hardware Development, Linux, openSuSE, Raspberry Pi, SuSE Linux, Tumbleweed | Leave a Comment »

OpenSuSE Tumbleweed on Raspberry Pi: using Hexxeh/rpi-update to update the firmware

Posted by jpluimers on 2017/04/04

https://raw.githubusercontent.com/Hexxeh/rpi-update/master/rpi-update && sudo chmod +x /usr/bin/rpi-update

The above is suggested by Hexxeh/rpi-update: An easier way to update the firmware of your Raspberry Pi

This is what I did  on my OpenSuSE Tumbleweed powered Raspberry Pi devices:

statler:~ # cd bin
statler:~/bin # wget https://raw.githubusercontent.com/Hexxeh/rpi-update/master/rpi-update 
--2016-08-30 13:04:38--  https://raw.githubusercontent.com/Hexxeh/rpi-update/master/rpi-update
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 151.101.36.133
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|151.101.36.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 12022 (12K) [text/plain]
Saving to: ‘rpi-update’

rpi-update          100%[===================>]  11.74K  --.-KB/s    in 0.002s  

2016-08-30 13:04:39 (6.36 MB/s) - ‘rpi-update’ saved [12022/12022]

statler:~/bin # ls -al
total 20
drwxr-xr-x 2 root root  4096 Aug 30 13:04 .
drwx------ 4 root root  4096 Aug 30 13:04 ..
-rw-r--r-- 1 root root 12022 Aug 30 13:04 rpi-update
statler:~/bin # chmod 755 rpi-update 
statler:~/bin # ./rpi-update 
 *** Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS and Dom
 *** Performing self-update
 *** Relaunching after update
 *** Raspberry Pi firmware updater by Hexxeh, enhanced by AndrewS and Dom
 *** We're running for the first time
 *** Backing up files (this will take a few minutes)
 *** Backing up firmware
 *** Backing up modules 4.1.19-1-rpi2
This update bumps to rpi-4.4.y linux tree
Be aware there could be compatibility issues with some drivers
Discussion here:
https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=144087
##############################################################
 *** Downloading specific firmware revision (this will take a few minutes)
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   168    0   168    0     0    382      0 --:--:-- --:--:-- --:--:--   382
100 51.2M  100 51.2M    0     0  1511k      0  0:00:34  0:00:34 --:--:-- 1298k
 *** Updating firmware
 *** Updating kernel modules
 *** depmod 4.4.19+
 *** depmod 4.4.19-v7+
 *** Updating VideoCore libraries
 *** Using HardFP libraries
 *** Updating SDK
 *** Running ldconfig
 *** Storing current firmware revision
 *** Deleting downloaded files
 *** Syncing changes to disk
 *** If no errors appeared, your firmware was successfully updated to 818a860cf690d64c62d3227ad9c36d5867a671c2
 *** A reboot is needed to activate the new firmware
statler:~/bin # reboot

Then on the console:

U-Boot 2016.07 (Aug 12 2016 - 14:07:49 +0000)

DRAM:  880 MiB
RPI 2 Model B (0xa21041)
MMC:   bcm2835_sdhci: 0
reading uboot.env

** Unable to read "uboot.env" from mmc0:1 **
Using default environment

In:    serial
Out:   lcd
Err:   lcd
Net:   Net Initialization Skipped
No ethernet found.
starting USB...
USB0:   Core Release: 2.80a
scanning bus 0 for devices... 4 USB Device(s) found
       scanning usb for storage devices... 0 Storage Device(s) found
       scanning usb for ethernet devices... 1 Ethernet Device(s) found
Hit any key to stop autoboot:  0 
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1...
Scanning mmc 0:2...
Found U-Boot script /boot.scr
2781 bytes read in 50 ms (53.7 KiB/s)
## Executing script at 02000000
switch to partitions #0, OK
mmc0 is current device
5352616 bytes read in 1003 ms (5.1 MiB/s)
6088968 bytes read in 1010 ms (5.7 MiB/s)
14226 bytes read in 138 ms (100.6 KiB/s)
Kernel image @ 0x1000000 [ 0x000000 - 0x51aca8 ]
## Flattened Device Tree blob at 00000100
   Booting using the fdt blob at 0x000100
   Using Device Tree in place at 00000100, end 00006891

Starting kernel ...

Uncompressing Linux... done, booting the kernel.

Welcome to openSUSE Tumbleweed 20160828 - Kernel 4.1.19-1-rpi2 (ttyAMA0).


statler login: 
...
statler:~ # /opt/vc/bin/vcgencmd version
/opt/vc/bin/vcgencmd: error while loading shared libraries: libvchiq_arm.so: cannot open shared object file: No such file or directory

statler:~ # locate libvchiq_arm.so
-bash: locate: command not found

statler:~ # zypper install findutils-locate
....

statler:~ # locate libvchiq_arm.so
locate: can not stat () `/var/lib/mlocate/mlocate.db': No such file or directory

statler:~ # /usr/bin/updatedb
statler:~ #  locate libvchiq_arm.so
/opt/vc/lib/libvchiq_arm.so

–jeroen

Posted in Development, Hardware Development, Raspberry Pi | Leave a Comment »

Powering Raspberry Pi devices from a Fritz!Box USB connection

Posted by jpluimers on 2017/03/30

I tried to power both Raspberry B+ and Raspberry 2 B devices via the USB ports of both a Fritz!Box 7490 and Fritz!Box 7360.

At first this works, but the Raspberry B+ devices over time would become unstable: not being able to ping and/or boot.

So below are some links on power requirements and powering Raspberry Pi A, B, A+, B+, 2B and zero.

Fazit/TL;DR: use an external power supply when available.

Read the rest of this entry »

Posted in *nix, Development, Fritz!, Fritz!Box, Hardware Development, Internet, Linux, openSuSE, Power User, Raspberry Pi, SuSE Linux | Leave a Comment »

Mac OS X – serial communication programs

Posted by jpluimers on 2017/03/30

Some links that helped me getting FTDI USB serial communication to Raspberry Pi systems going:

–jeroen

Posted in Apple, Communications Development, Development, Hardware Development, Hardware Interfacing, iMac, Legacy Ports: COM, Mac, Mac OS X / OS X / MacOS, MacBook, MacBook Retina, MacBook-Air, MacBook-Pro, MacMini, OS X 10.10 Yosemite, OS X 10.9 Mavericks, Power User, Raspberry Pi, USB | Leave a Comment »

`-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)` on fresh Raspbian on Raspberry

Posted by jpluimers on 2017/03/24

Every time I logged onto a freshly installed Rasbian system (Debian Jessie), I had this message:

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sat Aug 27 19:52:33 2016 from 192.168.171.24
-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)

Asking for the locale settings would give this:

jeroenp@raspberrypi:~ $ locale
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_GB.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=en_US.UTF-8

Searching for raspbian jessie “-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)” I found fix locale issue #15 · scaleway/image-debian@543e9b4 [WayBack] that fixes Locale issue on Debian Jessie · Issue #15 · scaleway/image-debian · GitHub [WayBack]:

When logging into to a freshly booted debian jessie image:

-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
-bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)

Source: Locale issue on Debian Jessie · Issue #15 · scaleway/image-debian

I changed the crux of that solution to this one:

echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen && locale-gen

When running, it showed this:

# echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen && locale-gen
Generating locales (this might take a while)...
  en_GB.UTF-8... done
  en_US.UTF-8... done
Generation complete.

And logging this:

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sat Aug 27 20:26:34 2016 from 192.168.171.24

Problem solved: 1 line of code!

–jeroen

Posted in *nix, Arduino, Debian, Development, Hardware Development, Linux, Power User, Raspberry Pi, Raspbian | 1 Comment »

KPN LoRa om Van Raam fietsen te traceren Zakelijk KPN Forum

Posted by jpluimers on 2017/03/02

Interesting: [Archive.isKPN LoRa om Van Raam fietsen te traceren Zakelijk KPN Forum via [WayBackNederlands bedrijf komt met narrowband-internet-of-things-ontwikkelbordje – Computer – Nieuws – Tweakers

–jeroen

Posted in Arduino, Development, Hardware Development, Hardware Interfacing | Leave a Comment »

230 V safety on the work bench – Put your power supply in an old tablet container…

Posted by jpluimers on 2017/02/28

Great tip from Nelis Willers:

230 V safety on the work bench.
Put your power supply in an old tablet container. The high voltage is safely encapsulated and will not accidentally touch something. Of course don’t do this for a kW supply, only where low heat is generated, otherwise you might set a fire!

Source: 230 V safety on the work bench. Put your power supply in an old tablet container…

Posted in Development, Hardware Development, LifeHacker, Power User | Leave a Comment »