RTL-SDR V4 and a Pi B

TL;DR This below didn’t go well, the Pi kept rebooting when the SDR was connected. I assume hardware related. Next is an attempt with a newer Pi 3.

May in future refer back to steps here.

Having tested the RTL-SDR Blog V2 on my laptop next up is to see if it will run on my Raspberry PI, a 2012 Pi Model B Rev2

RTL-SDR Driver install

Per the V4 Users Guide, the approach to getting a driver differs for various systems. For Debian GNU/Linux, the driver is grabbed from their github and compiled.

NB - they have two methods

1. building the source and using make install
2. building via dpkg-buildpackage

I’m going to try the first one…

Source build

Cleaning old drivers from your system

1. Initial steps are purging older drivers:

   sudo apt purge ^librtlsdr
   

   but I didn’t have any of those installed (output).

2. Then to remove previous user-built drivers if any:

   sudo rm -rvf /usr/lib/librtlsdr* /usr/include/rtl-sdr* /usr/local/lib/librtlsdr* /usr/local/include/rtl-sdr* /usr/local/include/rtl_* /usr/local/bin/rtl_*
   

   but again i didn’t have any of that either (output).

Preparing for Source Build

1. Getting Driver build pre-requisites.
   • Before grabbing their driver code and building, you need to make sure you have a few pieces ready.
   • In addition to the things specified here, you will also see those each may have further dependancies which will also be installed.

     sudo apt-get install libusb-1.0-0-dev git cmake pkg-config 
     

     I initially got an error there, but after running a quick package-manager update via sudo apt-get update and then a retry it worked fine. (output)

2. Grabbing the driver code is a simple git command, and it will create a folder called by the name of the repository (rtl-sdr-blog).

   git clone https://github.com/rtlsdrblog/rtl-sdr-blog
   

   (output)

3. Checking the system, build tools and config are next . I hadn’t used cmake before, and read around to find it is a successor of ./configure for generating a Makefile after performing some platform and environment checks. More on their wiki. Those few prep commands involved in this step comprise:

   cd rtl-sdr-blog/
   mkdir build
   cd build
   cmake ../ -DINSTALL_UDEV_RULES=ON
   

   and again, output for reference.

Building

At this stage, we’re ready to build the driver. This command is as easy at it gets, just type make :D

make

This takes about 6minutes on the Model B Pi. output.

Install the built driver

Down to the final hurdles.

1. Install will copy the built libraries and make them available for runtime use

   sudo make install
   

   output.

2. Copy the driver rules for udev, becuase “…udev allows for rules that specify what name is given to a device, regardless of which port it is plugged into…. This consistent naming of devices guarantees that scripts dependent on a specific device’s existence will not be broken.” ref

   sudo cp ../rtl-sdr.rules /etc/udev/rules.d/ 
   

3. Configure the dynamic linker as “…ldconfig creates the necessary links and cache to the most recent shared libraries…“ ref

   sudo ldconfig
   

4. And blacklist some DVB-T TV Drivers so they aren’t inadvertently used instead I guess.

   pi@rasppi:~/rtl-sdr-blog/build $ echo 'blacklist dvb_usb_rtl28xxu' | sudo tee --append /etc/modprobe.d/blacklist-dvb_usb_rtl28xxu.conf
   blacklist dvb_usb_rtl28xxu
   

Reboot

This is all wrapped up in sudo shutdown -r now :

pi@rasppi:~/rtl-sdr-blog/build $ sudo shutdown -r now
Connection to rasppi closed by remote host.
Connection to rasppi closed.

Connect the SDR

I wasn’t sure how the PI would behave when the SDR was connected, so I ran dmesg -w to tail the system messages.

Trouble

Unfortunately, the next message i saw was a couple of minutes later - i got disconnected.

client_loop: send disconnect: Broken pipe

I unplugged the RTL SDR device, and was able to reconnect to the Pi, but by that time it seemed like what had happened was the system had reset/restarted.

Sure enough when i checked the “update” it reported only 3 minutes !

pi@rasppi:~ $ uptime
20:34:19 up 3 min,  2 users,  load average: 0.34, 0.57, 0.27

Troubleshooting

Unfortunately checking various logs doesn’t offer any insights…

tail /var/log/syslog
tail /var/log/daemon.log
tail /var/log/kern.log

…everything seems fine up until 28 minutes after the hour, and then nothing until 31minutes after, which is startup related messages :(

Various¹ threads² online³ point to power issues as the most likely culprit.

The second link there suggests how vcgencmd may be used to check throttling, temperature and voltage.

I wrote a little script that runs each vcgencmd check on a loop with a sleep for 1 second between each round, hoping it might offer some clues about the restarts:

#!/bin/bash
function checkem ()
{
	echo `date` >> vc-throttle.txt
	vcgencmd get_throttled >> vc-throttle.txt

	echo `date` >>  vc-temp.txt
	vcgencmd measure_temp >> vc-temp.txt

	echo `date` >> vc-volt.txt
	vcgencmd measure_volts >> vc-volt.txt
}

while [[ true ]] ; do
	checkem
	sleep 2
done

I also had a look at reducing power use, e.g. this article from 2021 about power optimisation.

• Powering off HDMI and maybe the L.E.D.s seem like good options.
• Unsure about down-clocking CPU.
• USB is needed for the SDR
• this Pi doesnt’ have Wifi/Bluetooth.

To turn off HDMI to see if I could get a little extra juice, this worked on the OS Version (Raspbian GNU/Linux 10 (buster))

pi@rasppi:~ $ tvservice -o
Powering off HDMI

While I’m typing this, it has remained on …..

Testing the driver and device

There are various command-line options available to test the SDR, without needing to install anything further.

pi@rasppi:~ $ rtl_
rtl_adsb    rtl_biast   rtl_eeprom  rtl_fm      rtl_power   rtl_sdr     rtl_tcp     rtl_test    

rtl_test

rtl_test, “a benchmark tool for RTL2832 based DVB-T receivers”, seems like a nice simple option so I gave that a go.

pi@rasppi:~ $ rtl_test -p
Found 1 device(s):
  0:  RTLSDRBlog, Blog V4, SN: 00000001

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R828D tuner
RTL-SDR Blog V4 Detected
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6 
Sampling at 2048000 S/s.
Reporting PPM error measurement every 10 seconds...
Press ^C after a few minutes.
Reading samples in async mode...
lost at least 20 bytes

After the report of “lost” bytes, nothing else arrived at the console.

Background for that tool is at this link.

That discussion mentions dump1090, a utility for handling Mode S (ADS-B) messages transmitted from aircraft on 1090 MHz with heading, speed, altitude etc for colission avoidance. Fun for future!

More trouble :( After a while, I tried to kill that rtl_test command, but again the device had reset.

Checking the throttle, temp and volt outputs (had been running in the background) showed no obvious culprit…

I’m now thinking of the Pi3 I have here too, time to switch devices perhaps. To be continued…

Appendices

Appendix A: Output - Removing old drivers

pi@rasppi:~ $ sudo apt purge ^librtlsdr
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Note, selecting 'librtlsdr-dev' for regex '^librtlsdr'
Note, selecting 'librtlsdr0' for regex '^librtlsdr'
Note, selecting 'librtlsdr0-dbgsym' for regex '^librtlsdr'
Package 'librtlsdr-dev' is not installed, so not removed
Package 'librtlsdr0' is not installed, so not removed
Package 'librtlsdr0-dbgsym' is not installed, so not removed
0 upgraded, 0 newly installed, 0 to remove and 156 not upgraded.

back

Appendix B: Output - Purging old user-built drivers

I did double check via ls to be sure.

pi@rasppi:~ $ sudo ls -al /usr/lib/librtlsdr* /usr/include/rtl-sdr* /usr/local/lib/librtlsdr* /usr/local/include/rtl-sdr* /usr/local/include/rtl_* /usr/local/bin/rtl_*
ls: cannot access '/usr/lib/librtlsdr*': No such file or directory
ls: cannot access '/usr/include/rtl-sdr*': No such file or directory
ls: cannot access '/usr/local/lib/librtlsdr*': No such file or directory
ls: cannot access '/usr/local/include/rtl-sdr*': No such file or directory
ls: cannot access '/usr/local/include/rtl_*': No such file or directory
ls: cannot access '/usr/local/bin/rtl_*': No such file or directory

back

Appendix C: Output - installing dependancies

pi@rasppi:~ $ sudo apt-get install libusb-1.0-0-dev git cmake pkg-config 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
pkg-config is already the newest version (0.29-6).
The following additional packages will be installed:
  cmake-data git-man libarchive13 liberror-perl libjsoncpp1 librhash0 libusb-1.0-doc libuv1
Suggested packages:
  cmake-doc ninja-build git-daemon-run | git-daemon-sysvinit git-doc git-el git-email git-gui gitk gitweb git-cvs git-mediawiki git-svn lrzip
The following NEW packages will be installed:
  cmake cmake-data git git-man libarchive13 liberror-perl libjsoncpp1 librhash0 libusb-1.0-0-dev libusb-1.0-doc libuv1
0 upgraded, 11 newly installed, 0 to remove and 156 not upgraded.
Need to get 10.8 MB of archives.
After this operation, 57.4 MB of additional disk space will be used.
Do you want to continue? [Y/n] yes

back

Appendix D: Output - git clone

pi@rasppi:~ $ git clone https://github.com/rtlsdrblog/rtl-sdr-blog 
Cloning into 'rtl-sdr-blog'...
remote: Enumerating objects: 2314, done.
remote: Counting objects: 100% (875/875), done.
remote: Compressing objects: 100% (135/135), done.
remote: Total 2314 (delta 792), reused 740 (delta 740), pack-reused 1439 (from 1)
Receiving objects: 100% (2314/2314), 737.97 KiB | 671.00 KiB/s, done.
Resolving deltas: 100% (1651/1651), done.

back

Appendix E: Output - build prep

pi@rasppi:~ $ cd rtl-sdr-blog 
pi@rasppi:~/rtl-sdr-blog $ mkdir build 
pi@rasppi:~/rtl-sdr-blog $ cd build 
pi@rasppi:~/rtl-sdr-blog/build $ cmake ../ -DINSTALL_UDEV_RULES=ON 
-- The C compiler identification is GNU 8.3.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Build type not specified: defaulting to release.
-- Extracting version information from git describe...
-- Looking for pthread.h
-- Looking for pthread.h - found
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Failed
-- Looking for pthread_create in pthreads
-- Looking for pthread_create in pthreads - not found
-- Looking for pthread_create in pthread
-- Looking for pthread_create in pthread - found
-- Found Threads: TRUE  
-- Found PkgConfig: /usr/bin/pkg-config (found version "0.29") 
-- Checking for module 'libusb-1.0'
--   Found libusb-1.0, version 1.0.22
-- Building with kernel driver detaching disabled, use -DDETACH_KERNEL_DRIVER=ON to enable
-- Building with usbfs zero-copy support disabled, use -DENABLE_ZEROCOPY=ON to enable
-- Performing Test COMPILER_HAS_HIDDEN_VISIBILITY
-- Performing Test COMPILER_HAS_HIDDEN_VISIBILITY - Success
-- Performing Test COMPILER_HAS_HIDDEN_INLINE_VISIBILITY
-- Performing Test COMPILER_HAS_HIDDEN_INLINE_VISIBILITY - Failed
-- Performing Test COMPILER_HAS_DEPRECATED_ATTR
-- Performing Test COMPILER_HAS_DEPRECATED_ATTR - Success
-- Building for version: 0.6.0-128-g240b / 0.6git
-- Using install prefix: /usr/local
-- Configuring done
-- Generating done
-- Build files have been written to: /home/pi/rtl-sdr-blog/build

back

Appendix F: Output - build

pi@rasppi:~/rtl-sdr-blog/build $ $ make
Scanning dependencies of target convenience_static
[  3%] Building C object src/CMakeFiles/convenience_static.dir/convenience/convenience.c.o
[  6%] Linking C static library libconvenience_static.a
[  6%] Built target convenience_static
Scanning dependencies of target rtlsdr
[  9%] Building C object src/CMakeFiles/rtlsdr.dir/librtlsdr.c.o
[ 12%] Building C object src/CMakeFiles/rtlsdr.dir/tuner_e4k.c.o
[ 15%] Building C object src/CMakeFiles/rtlsdr.dir/tuner_fc0012.c.o
[ 18%] Building C object src/CMakeFiles/rtlsdr.dir/tuner_fc0013.c.o
[ 21%] Building C object src/CMakeFiles/rtlsdr.dir/tuner_fc2580.c.o
[ 25%] Building C object src/CMakeFiles/rtlsdr.dir/tuner_r82xx.c.o
[ 28%] Linking C shared library librtlsdr.so
[ 28%] Built target rtlsdr
Scanning dependencies of target rtl_test
[ 31%] Building C object src/CMakeFiles/rtl_test.dir/rtl_test.c.o
[ 34%] Linking C executable rtl_test
[ 34%] Built target rtl_test
Scanning dependencies of target rtl_biast
[ 37%] Building C object src/CMakeFiles/rtl_biast.dir/rtl_biast.c.o
[ 40%] Linking C executable rtl_biast
[ 40%] Built target rtl_biast
Scanning dependencies of target rtl_tcp
[ 43%] Building C object src/CMakeFiles/rtl_tcp.dir/rtl_tcp.c.o
[ 46%] Linking C executable rtl_tcp
[ 46%] Built target rtl_tcp
Scanning dependencies of target rtl_sdr
[ 50%] Building C object src/CMakeFiles/rtl_sdr.dir/rtl_sdr.c.o
[ 53%] Linking C executable rtl_sdr
[ 53%] Built target rtl_sdr
Scanning dependencies of target rtl_power
[ 56%] Building C object src/CMakeFiles/rtl_power.dir/rtl_power.c.o
[ 59%] Linking C executable rtl_power
[ 59%] Built target rtl_power
Scanning dependencies of target rtlsdr_static
[ 62%] Building C object src/CMakeFiles/rtlsdr_static.dir/librtlsdr.c.o
[ 65%] Building C object src/CMakeFiles/rtlsdr_static.dir/tuner_e4k.c.o
[ 68%] Building C object src/CMakeFiles/rtlsdr_static.dir/tuner_fc0012.c.o
[ 71%] Building C object src/CMakeFiles/rtlsdr_static.dir/tuner_fc0013.c.o
[ 75%] Building C object src/CMakeFiles/rtlsdr_static.dir/tuner_fc2580.c.o
[ 78%] Building C object src/CMakeFiles/rtlsdr_static.dir/tuner_r82xx.c.o
[ 81%] Linking C static library librtlsdr.a
[ 81%] Built target rtlsdr_static
Scanning dependencies of target rtl_eeprom
[ 84%] Building C object src/CMakeFiles/rtl_eeprom.dir/rtl_eeprom.c.o
[ 87%] Linking C executable rtl_eeprom
[ 87%] Built target rtl_eeprom
Scanning dependencies of target rtl_fm
[ 90%] Building C object src/CMakeFiles/rtl_fm.dir/rtl_fm.c.o
[ 93%] Linking C executable rtl_fm
[ 93%] Built target rtl_fm
Scanning dependencies of target rtl_adsb
[ 96%] Building C object src/CMakeFiles/rtl_adsb.dir/rtl_adsb.c.o
[100%] Linking C executable rtl_adsb
[100%] Built target rtl_adsb

back

Appendix G: Output - make install

pi@rasppi:~/rtl-sdr-blog/build $ sudo make install
[  6%] Built target convenience_static
[ 28%] Built target rtlsdr
[ 34%] Built target rtl_test
[ 40%] Built target rtl_biast
[ 46%] Built target rtl_tcp
[ 53%] Built target rtl_sdr
[ 59%] Built target rtl_power
[ 81%] Built target rtlsdr_static
[ 87%] Built target rtl_eeprom
[ 93%] Built target rtl_fm
[100%] Built target rtl_adsb
Install the project...
-- Install configuration: "Release"
-- Installing: /etc/udev/rules.d/rtl-sdr.rules
-- Installing: /usr/local/include/rtl-sdr.h
-- Installing: /usr/local/include/rtl-sdr_export.h
-- Installing: /usr/local/lib/pkgconfig/librtlsdr.pc
-- Installing: /usr/local/lib/cmake/rtlsdr/rtlsdrTargets.cmake
-- Installing: /usr/local/lib/cmake/rtlsdr/rtlsdrTargets-release.cmake
-- Installing: /usr/local/lib/cmake/rtlsdr/rtlsdrConfig.cmake
-- Installing: /usr/local/lib/cmake/rtlsdr/rtlsdrConfigVersion.cmake
-- Installing: /usr/local/lib/librtlsdr.so.0.6git
-- Installing: /usr/local/lib/librtlsdr.so.0
-- Installing: /usr/local/lib/librtlsdr.so
-- Installing: /usr/local/lib/librtlsdr.a
-- Installing: /usr/local/bin/rtl_sdr
-- Set runtime path of "/usr/local/bin/rtl_sdr" to ""
-- Installing: /usr/local/bin/rtl_tcp
-- Set runtime path of "/usr/local/bin/rtl_tcp" to ""
-- Installing: /usr/local/bin/rtl_test
-- Set runtime path of "/usr/local/bin/rtl_test" to ""
-- Installing: /usr/local/bin/rtl_fm
-- Set runtime path of "/usr/local/bin/rtl_fm" to ""
-- Installing: /usr/local/bin/rtl_eeprom
-- Set runtime path of "/usr/local/bin/rtl_eeprom" to ""
-- Installing: /usr/local/bin/rtl_adsb
-- Set runtime path of "/usr/local/bin/rtl_adsb" to ""
-- Installing: /usr/local/bin/rtl_power
-- Set runtime path of "/usr/local/bin/rtl_power" to ""
-- Installing: /usr/local/bin/rtl_biast
-- Set runtime path of "/usr/local/bin/rtl_biast" to ""

back