Raspberry Pi (RPi) and Amateur Radio Resources

Here are a few resources you might find helpful for Linux and radio on PCs or RPis.

http://www.trinityos.com/HAM/index-ham.html

• Ham radio software on CentOS Linux
• Getting Started with Packet Radio
• Raspberry Pi APRS and Packet Radio
• APRS beginner's guide
• Amateur Radio and Linux: Opening Doors without Windows

Raspberry Pi for Ham Radio Yahoo Group - a fairly active Yahoo Group. Yahoo Group Description:

This is a place for Amateur Radio Ops to discuss the Raspberry Pi and how it can be applied to Ham Radio.  This is a moderated Group. Please keep posts civil and on topic. (Any discussion of the RPi is welcome)

• https://groups.yahoo.com/neo/groups/Raspberry_Pi_4-Ham_RADIO/info

Info on Intel's AMT with an open source client.

Found this blog entry,  "Everything you need to know about Intel AMT and the Intel NUC with Ubuntu" on Dustin Kirkland's blog. AMT is vaguely related to IPMI, but is somewhat Intel proprietary. The key bit of info is there is a package available for Ubuntu, amtterm, that has a command, amttool that can be used for remote management of systems with AMT built-in (Intel VPro) and enabled.

Automate Cygwin package installation, search for packages from the command line, grep the list of installed packges.

Stumbled across two things for improving life when dealing with Cygwin.  (Cygwin is a port of Unix-like GNU tools for Windows.)

First, the standard Cygwin-setup utility takes command line arguments that will avoid all of the prompts, so you can have a single command to update a system without having to do a lot of clicking.   See this blog post from Cody Dunne.

Put this in a batch file, run it as administrator:

cd C:\cygwin
wget -N http://cygwin.com/setup-x86.exe
setup-x86.exe --no-desktop --no-shortcuts --no-startmenu --quiet-mode

Or if you are typing it by hand:

setup-x86 -nNdq

Second, there is a nice command link apt-get like utility, called apt-cyg. It's a neat, simple bash script. Nothing to really install. Provides command like search, and text access to the list of installed packages. apt-cyg is in Stephen Jungel's github repo.

Note: the key data is in the setup INI files stored in cygwin-pkgs/mirror-name/x86/setup.ini.

Hope this helps,
--Rob

Acurite 592TXR Temperature and Humidity Sensors now decoded by rtl_433.

I've added decoding of Acurite's 592TXR "Tower" temperature and humidity sensors to rtl_433. These are small, inexpensive, wirelesss (433 Mhz), temperature and humidity sensors. The 592TXR has several different model numbers including 06002RM

These are compatible with Acurite's consoles such as the 01512 that I have as well as Acurite's Acu-Link Internet bridge which posts to acu-link's web page as well as weatherunderground. I picked up the Acurite 5-n-1 Weather Station, a console, and the internet bridge because the support for the 5-n-1 had been added to rtl_433 and the package price was pretty reasonable.

There were a number of people interested in decoding the 592TXR, but for some reason, it never got added, so I finally added it and cleaned up the Acurite 5-n-1 weather station decoding. The pull request got merged November 8th, 2015.

I think the temperature only version, the 592TX, should also be supported but I don't have one to test. Please let me know if it decodes successfully or not.

The protocol used by the Acurite 592TXR and the 5-n-1 weather station are very similar. The weather station's messages are one byte longer, but they are basically the same with the same RF signaling characteristics.

Remotely monitor Refrigerator / Freezer temperature with Acurite 986 and rtl_433 (rtl-sdr)

I suspected the thermostat in my basement refrigerator was going bad, so I picked up an Acurite 986 refrigerator and freezer remote thermometer.  The display unit will give alarms if the temperature goes out of range.

I wanted a better picture of what was going on so I figured out the Acurite's 433 mhz protocol for the 986 sensors. I've added support to rtl_433. The pull request was merged November 20th, 2015.

Now I pump the data into rrdtool and see what's going on. I now see how long and often the compressor is running, and how long it times to warm up between cycles. The spikes are the defrost cycles.

Now I can also monitor/get alerted when I'm out of the house.

I'm pretty happy with the Acurite 986 display and temperature sensors even without the rtl_433 decoding.

Acurite 00986 Refrigerator / Freezer Thermometer Protocol

• Includes two sensors and a display, labeled 1 and 2, by default Sensor 1 - Refrigerator, 2 - Freezer.
• Data format: Pulse Position Modulated (PPM), 5 bytes, sent twice, no gap between repeaters
• Start/sync pulses: two short, with short gaps, followed by 4 long pulse/gaps.
• Data Format - 5 bytes, sent LSB first, reversed
• TT II II SS CC
• TT - Temperature in Fahrenehit
• integer, 
• MSB = sign. Encoding is "Sign and magnitude"
• II - 16 bit sensor ID changes at each power up
• SS - status/sensor type
• 0x01 = Sensor 2 (
• 0x02 = low battery
• CC = CRC (CRC-8 polynomial 0x07, little-endian) 

I was able to easily figure out the CRC with CRC RevEng..

Another Yaesu VX-8DR external GPS with an Arduino/ATmega328 translator.

I've collected links for a few of these projects to add a better external GPS to the Yaesu VX-8DR, instead of the somewhat proprietary Yaesu option.

Here's another one from VK3YY that got posted recently:

• https://vk3yy.wordpress.com/2015/07/24/vx-8dr-and-gps/ 

Here's code from DFannin on github:

• Arduino code for buidling Yaesu VX8r Handheld Transmitter-compatible GPS

Update 2016-01-15, 4Z7DTF notified me about his project, which includes more additional analysis of how poor the VX-8's parsing and error handling is.

•  4Z7DTF's VX-8 Arduino GPS interface on github 

Background Info:

Good detailed blog post Reverse Engineering the Yaesu VX-8DR GPS Interface. From Feb. 2013. He didn't arrive at the solution, which I believe F4FXL and at least one other have. But I think he's got most of the relevant details for the padding differences listed as well as some other very useful info including details on the GPS chips used in VX-8 and VX-8G.

We now know how to connect to and send a properly formatted GPS NMEA message to the Yaesu VX-8DR. Here's the summary:

• 9600baud TTL 3.3V serial signalling, 8/N/1
  • NOT RS232 -5 to +5V signalling -- you need a level converter if that's all you have
• 3-wire physical interface to the following pins:
  

  Pin	GPS Side Purpose	Yaesu Side Purpose
  4	GPS RX	Yaesu TX
  5	GPS TX	Yaesu RX
  6	GPS GND	Yaesu GND

• According to 4Z7DTF (2016-01-15), there is no need for the communication to be bidirectional. Only the TX Data from the GPS to the VX-8 is required.

The messages need to be formatted exactly as follows: Message Type Source Sentence $GPGGA Sample $GPGGA,123223.000,4131.2334,N,00021.1216,E,1,04,02.7,00123.4,M,0051.7,M,000.0,0000*41 Syntax $GPGGA,hhmmss.sss,llll.llll,a,yyyyy.yyyy,a,x,xx,xx.x,xxxxx.x,M,xxxx.x,M,xxx.x,xxxx*hh $GPRMC Sample $GPRMC,123223.000,A,4131.2334,N,00021.1216,E,0000.00,291.33,301011,,*3E Syntax $GPRMC,hhmmss.sss,A,llll.llll,a,yyyyy.yyyy,a,xxxx.xx,xxx.xx,xxxxxx,,*hh $GPZDA Sample $GPZDA,123223.000,30,10,2011,,*55 Syntax $GPZDA,hhmmss.sss,xx,xx,xxxx,,*hh

rtl_433 now decodes DSC 433 Mhz wireless securty contacts

** UPDATE For status bit decoding see rtl_433 DSC Status Bit Decoding **

If you have a DSC (Digital Security Controls) home security system, with wireless sensors such as door / window contacts, glass break detectors, smoke, CO2, heat, and water detectors, you can now monitor them with rtl_433. The code is now in the mainline Merbanan github repo.

Only the 433 Mhz security sensors/contacts devices are currently supported.  I will be working on other devices soon. I have almost all of the status bits worked out. I will be submitting a pull request soon.

DSC alarm systems are also sold under other brands such as ADT Pulse, and a number of cable/telephone company's home automation systems, such as Time Warner Intelligent Home. DSC is a division of Tyco, so you will also see DSC products listed as Tyco Security, though Tyco has a whole list of security brands.

These are fairly inexpensive wireless devices that can also be useful for a variety of home automation projects.

The DSC WS4945 - Wireless Door and Window contact can be used as a magnetic contact or used with any sort of sensor that provides a normally closed output. If you are using it for home automation without a security system, it doesn't matter if it is normally closed or normally open. It will transmit at any state change. The device also sends a heartbeat with the current state every 64 minutes.

The Vanishing door/window contact, EV-DW4975 is quite thin and small if you don't need the screw terminals for wiring up some other type of sensor. It will barely be noticed on most doors and windows.

If you are interested in decoding DSC's wireless protocols, or have any information to share, please contact me, I could certainly use someone to collaborate with.

** UPDATE For status bit decoding see rtl_433 DSC Status Bit Decoding **