Installing software onto the Raspberry Pi- Part 2

Finally here's where we install the Linux software for monitoring the Smart Meter!
Based on the previous work done for the testing on a Windows PC, we are going to need:

• rtl-sdr drivers
• rtl-tcp server
• rtlamr decoder

But instead of Windows sources, we are going to need the ones for Raspbian.

RTL-SDR / RTL-TCP

The following post was extremely helpful in setting up the rtlsdr software on the RPi:

https://photobyte.org/using-the-raspberry-pi-as-an-rtl-sdr-dongle-server/

• First we need to install some packages required by the rtl-sdr dongle server:

$ sudo apt-get update $ sudo apt-get install -y cmake pkg-config libusb-1.0-0-dev

• Instead of going to the NooElec website for pre-compiled Windows drivers, we will get the sources from:
  
  http://osmocom.org/projects/sdr/wiki/Rtl-sdr
  
  Fortunately 'git' is already included with the installed OS, so we can execute the following directly in /home/pi to get the rtl-sdr code:

(Note that in order for certificates to work for https access, you must have your OS set to the correct date and time !!

If you need to reload certificates, see https://stackoverflow.com/questions/35821245/github-server-certificate-verification-failed)

$ cd Documents $ git clone https://git.osmocom.org/rtl-sdr

• We can now run the following (note it may take some time to complete):

$ cd rtl-sdr $ mkdir build $ cd build $ cmake ../ -DINSTALL_UDEV_RULES=ON $ make $ sudo make install $ sudo ldconfig

• Before we can install the rtl-sdr USB dongle, we need to setup a 'blacklist' file to prevent the standard USB Radio/TV drivers from loading. Create the file 

/etc/modprobe.d/blacklist-rtl.conf

         
         and add the following lines to it: 

blacklist dvb_usb_rtl28xxu blacklist rtl2832 blacklist rtl2830

• You can now reboot the RPi, install the rtl-sdr dongle, and run rtl_test  

(use Ctrl+C to exit the test):

$ rtl_test Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000001 Using device 0: Generic RTL2832U OEM Found Rafael Micro R820T tuner 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 [R82XX] PLL not locked! Sampling at 2048000 S/s. Info: This tool will continuously read from the device, and report if samples get lost. If you observe no further output, everything is fine. Reading samples in async mode...

RTLAMR

• Before we can download and build rtlamr, we need to install the go build environment

https://golang.org/

(since this is for the RPi, we will need to get the version that runs on the ARM processor;  
as of this posting, the latest go release is 1.10):

$ cd /home/pi/Documents $ mkdir go_src $ cd go_src $ wget https://storage.googleapis.com/golang/go1.10.linux-armv6l.tar.gz $ sudo tar -C /usr/local -xvf go1.10.linux-armv6l.tar.gz $ cat >> ~/.bashrc << 'EOF' $ export GOPATH=$HOME/go $ export PATH=/usr/local/go/bin:$PATH:$GOPATH/bin $ EOF $ source ~/.bashrc.

• If all has run successfully, you can now check the go version:

$ go version go version go1.10 linux/arm

• We can now download and build bemasher's rtlamr from

https://github.com/bemasher/rtlamr

$ go get github.com/bemasher/rtlamr $ which rtlamr /home/pi/go/bin/rtlamr

• You can now start up rtl_tcp in a terminal session:

$ rtl_tcp Found 1 device(s): 0: Realtek, RTL2838UHIDIR, SN: 00000001 Using device 0: Generic RTL2832U OEM Found Rafael Micro R820T tuner [R82XX] PLL not locked! Tuned to 100000000 Hz. listening... Use the device argument 'rtl_tcp=127.0.0.1:1234' in OsmoSDR (gr-osmosdr) source to receive samples in GRC and control rtl_tcp parameters (frequency, gain, ...). client accepted! set freq 912600155 set sample rate 2359296 set gain mode 0

• And then start up rtlamr in a different terminal:

$ rtlamr 12:39:18.308293 decode.go:43: CenterFreq: 912600155 12:39:18.308772 decode.go:44: SampleRate: 2359296 12:39:18.308848 decode.go:45: DataRate: 32768 12:39:18.308895 decode.go:46: ChipLength: 72 12:39:18.308954 decode.go:47: PreambleSymbols: 21 12:39:18.309007 decode.go:48: PreambleLength: 3024 12:39:18.309058 decode.go:49: PacketSymbols: 96 12:39:18.309109 decode.go:50: PacketLength: 13824 12:39:18.309162 decode.go:51: Preamble: 111110010101001100000 12:39:18.309216 main.go:94: GainCount: 29 {Time:2018-04-27T13:30:44.224 SCM:{ID:49366114 Type:12 Tamper:{Phy:02 Enc:00} Consumption: 3612700 CRC:0xAB83}}

Next steps:

• Configuring the meter reader software

Installing software onto the Raspberry Pi- Part 1

Now that the Raspberry Pi can access the internet, we can begin adding and configuring software.
One of the first things to do is log into the the RPi via SSH and run raspi-config:

We will:

• Update raspi-config
• Set Localization options
• Change Locale to 'en_US.UTF-8 UTF-8'
• Change Timezone to US-Eastern
• Change Keyboard Layout to match the new locale
• Change Wi-fi Country to 'US United States'
• Under Advanced Options
•  Expand Filesystem to use the entire microSD card

Now that we have plenty of space on the system disk, we can start installing software.
But how? Some options:

• From the RPi SSH terminal command line
• By downloading software packages onto the laptop and transferring them to the RPi for installation (WinSCP is good for this):

• Installing via the Rasperry Pi Desktop's Applications Menu -> Preferences -> Add/Remove Software.
• But we are running headless and there's no Desktop GUI!

While the first two options can be followed immediately, let's figure out how to get access to the RPi  Desktop. We want to use VNC (Virtual Network Computing) for graphical desktop sharing:

 https://www.raspberrypi.org/documentation/remote-access/vnc/README.md

On your Raspberry Pi, run the following commands to make sure you have the latest versions of software, including VNC Connect:

$ sudo apt-get update $ sudo apt-get upgrade $ sudo apt-get dist-upgrade $ sudo apt autoremove $ sudo apt-get clean $ sudo apt-get install realvnc-vnc-server realvnc-vnc-viewer

Now, enable VNC Server by running raspi-config and doing the following:

• Navigate to Interfacing Options.
  
• Scroll down and select VNC > Yes.

On the laptop you will need to download and install VNC Viewer so you can connect to VNC Server that is running on the RPi:

https://www.realvnc.com/en/connect/download/viewer/ 

Once it is installed, we can start VNC Viewer on the laptop, direct it to the IP address of the RPi and login with our default credentials:

 And we are in!:

 

Next steps: 

• Add more software!

Sharing your laptop's internet connection with your Raspberry Pi

In the previous post, we set up a headless Raspberry Pi and connected to it via a PuTTY SSH terminal session running over the local NIC. In order to update and install software onto the RPi, we will need to give it access to the Internet and all of its code respositories. For example, you will need this when you run 'sudo raspi-config' and need to select Option 8 to update to the latest script version:

Since it is the Windows laptop that has access to the global network, we will enable Internet Connection Sharing between the global interface and the local NIC so the RPi can route through the laptop to the web. I found a couple of references on how to do this, but encountered differences in behavior on Windows 7 and Windows 10.

https://raspberrypi.stackexchange.com/questions/23627/how-to-share-my-internet-connection-on-a-windows-computer-with-a-raspberry-pi

https://raspberrypi.stackexchange.com/questions/63153/connect-pi-to-windows-10-with-internet-connection-sharing 

 To get it working on the Windows 10 laptop:

• Go to the NIC that is connected to the outside world (in my case, this was my laptop's WiFi adapter) and enable Internet Connection Sharing:

• When ICS is enabled, the wired NIC will automatically be assigned an IP address of '192.168.137.1' with subnet '255.255.255.0'.

• Use PuTTY to login to the RPi at the IP address you found using Wireshark and edit the file /etc/dhcpcd.conf  to set a new static IP address and DNS server:


interface eth0
static ip_address=192.168.137.2
static routers=192.168.137.1
static domain_name_servers=192.168.137.1 8.8.8.8

• Reboot the RPi and login over SSH again using the new static IP address (192.168.137.2). You should be able to run 'sudo apt-get update' to download RPi updates from the global repository:
  
  
  

Next steps:

•  Installing software

Setting up a headless Raspberry Pi

At the end of my previous post on reading my Smart Meter, I said I wanted to move the monitoring hardware and software off of the PC and onto a dedicated Raspberry Pi. Since I wasn't getting to this task at home, I thought I would try to do it during lunch at the office. Unfortunately, I don't have access to as much equipment there, but then that's part of the challenge.

In the office I just have my laptop, with keyboard and monitors tethered to other systems.  I was planning on following the steps in this post on configuring the RPi without those devices, and only using a PuTTY SSH to establish a serial terminal connection:

https://hackernoon.com/raspberry-pi-headless-install-462ccabd75d0

However, I also do not have open access to the corporate network or router and am running Windows instead of Linux. There were some more tips here for a direct ethernet cable connection:

http://www.circuitbasics.com/how-to-connect-to-a-raspberry-pi-directly-with-an-ethernet-cable/

but the problem is I do not have a good way to determine the IP address that the RPi self-assigns when it boots. Then I remembered that I run the Wireshark protocol analyzer on my Linux systems, and there is also a Windows version available!

https://www.wireshark.org/

So here's the steps:

• On the Windows laptop, download the latest version of Raspian and burn the image to a microSD card.
• From a Windows command prompt, create a dummy file named 'ssh' and place it in the Linux boot directory located on the card (in this case, the card reader has assigned drive E to it).
• copy /b NUL ssh
• move ssh e:
• Eject the the microSD card and install it into the RPi.
• Connect the laptop and the RPi together with a standard ethernet cable.
• Power up the RPi and wait a couple of minutes for it to self-assign an IP address.
• On your laptop, start Wireshark and select the Ethernet interface to analyze:

• Examine the first few lines of the analysis to see what IP address the RPi is broadcasting from (in this case 169.254.12.109):

• Now that I know the IP address, I can log into the RPi using PuTTY:

• And we are in!!

Next steps:

•  Configure the RPi's network settings (e.g., set a static IP address)
•  Set up internet connection sharing on my laptop so I can update the RPi with the RTLSDR software:

http://thisdavej.com/connecting-a-raspberry-pi-using-an-ethernet-crossover-cable-and-internet-connection-sharing/