Nexus Utilities

VERSION 20221222

AUTHOR: Steve Magnuson, AG7GN

This is a collection of utilities for the Nexus image. These scripts will only work on the Nexus image.
Some scripts are specific to the Nexus DR-X board.

Check Piano script

Initialize Pi script

Name Radios script

Shutdown Button and LED script

Radio PTT Monitor script

Piano Switch Example script

Desktop Template files

Edit Desktop Text script

VNC Server Activity Reporting script

USB Device Manager

Installation

Install

• Click Raspberry > Hamradio > Nexus Updater.
• Check nexus-utils, click OK.

Check Piano script

check-piano.sh is run whenever the Pi starts. It reads the position of the piano switches on the Nexus DR-X board and launches a script based on which switch levers are up or down. The script is called by the autostart file located in /etc/xdg/lxsession/LXDE-pi. That file looks like this:

@lxpanel --profile LXDE-pi
@pcmanfm --desktop --profile LXDE-pi
@bash /usr/local/bin/check-piano.sh

The script that check-piano.sh calls (that is, the script you create) must be:

• In the user's home directory

• Marked as executable (run chmod +x pianoX.sh to make executable)

• Named pianoX.sh where X is one of these:

    1, 12, 13, 14, 123, 124, 134, 1234, 2, 23, 234, 24, 3, 34, 4
  

NOTE: If no switch levers are in the down position, piano.sh will run, so there are 16 possible lever positions and corresponding scripts.

Example 1: When the piano switch levers 2 and 4 are down, the script named $HOME/piano24.sh, if present and executable, will run whenever the Raspberry Pi starts.

Example 2: When no levers on the piano switch are down, the script named $HOME/piano.sh, if present and executable, will run whenever the Raspberry Pi starts.

See pianoX.sh.example for an example piano script.

If a pianoX.sh script is not present in the home folder, no action is taken and the pi boots normally.

Disabling the piano switch function

• Move all of the switches to the off (up) position.

• As sudo, open the /etc/xdg/lxsession/LXDE-pi file. One way to do this is to open Terminal, then run this command: sudo leafpad /etc/xdg/lxsession/LXDE-pi. Leafpad is like Notepad in Windows.

• Locate the line: @bash /usr/local/bin/check-piano.sh

• Insert # at the beginning of that line, so that the file looks like this:

    @lxpanel --profile LXDE-pi
    @pcmanfm --desktop --profile LXDE-pi
    #@bash /usr/local/bin/check-piano.sh
    @xscreensaver -no-splash
  

• Save the file and reboot the Pi

Initialize Pi script

initialize-pi.sh is run whenever the Pi starts. It runs via this line in user pi's crontab:

@reboot sleep 5 && /usr/local/bin/initialize-pi.sh

The script checks for the presence of a file called DO_NOT_DELETE_THIS_FILE in the user's home directory. If DO_NOT_DELETE_THIS_FILE is not present in the user's home directory, the script will reset various configuration files for ham radio applications to default values and reset the VNC Server and SSH keys. It will then create the DO_NOT_DELETE_THIS_FILE file in the user's home directory.

If DO_NOT_DELETE_THIS_FILE is present in the home folder, the script exits without taking any action.

Name Radios script

name-radios.sh allows you to change the title bar of Fldigi suite and Direwolf applications so they say something other than "Left Radio" or "Right Radio". The associated menu entry file is /usr/local/share/applications/nameradios.desktop.

Patmail script

patmail.sh allows the user to run pat within scripts rather than interactively. Obviously, pat must be installed for it to work. You can install Pat via Raspberry > Hamradio > Update Pi and Ham Apps.

Test Piano script

test-piano.sh allows you to test the operation of your pianoX.sh script by simulating what the check-piano.sh does when the Pi starts. Set the piano switches as desired, then open a Terminal and run test-piano.sh. The script will tell you which script will run based on which switch levers are down. It will not actually run the pianoX.sh script.

Direwolf APRS GUI

dw_aprs_gui.sh provides a GUI to configure Direwolf to process APRS traffic. It can configured as a generic digipeater (fill-in or full) and/or an iGate. You can also supply your own Direwolf configuration rather than using one of the generic configurations.

Direwolf and pat GUI

dw_pat_gui.sh provides a GUI to configure the Direwolf TNC and pat to make a functional Winlink email client on Nexus DR-X. It also provides a monitor window that shows messages from both Direwolf and pat.

If you make any changes in either of the Configure tabs, click Restart Direwolf and pat to activate the changes.

Monitor tab

Shows the output of the Direwolf TNC and pat applications. Near the top of the Monitor tab window, you’ll see a row that looks something like this:

AGW Port: 8001 KISS Port: 8011 pat Telnet Port: 8770 pat Web Server: http://nexus-ag7gn.local:8040

The first 3 items are port numbers that your Pi is listening on for various connections from other clients. Use the KISS port, for example, if you have Windows PCs running Winlink Express on the same network as your Pi.

The pat Web Server URL is what you’d use to access pat’s web server from your Pi (using the Chromium browser) or from another browser on another computer on your home network.

Configure TNC tab

Configures Direwolf for AX25, ready to be used with remote Windows PCs via KISS or with pat on Linux via pat’s command line interface or it’s web interface.

Configure pat tab

Configures the pat Winlink email client.

• Call Sign, Winlink Password, Locator Code

  These should be self explanatory.

• Web Service Port

  The port on which pat will listen for traffic from the pat web interface. Default is 8049.

• Telnet Service Port

  The port on which pat will listen for telnet traffic. Default is 8774.

• Start pat web service when ARDOP starts

  Checking Start pat web service when Direwolf TNC starts will start pat with the http server enabled. If this option is not checked, pat will not run at all. You can then run pat in interactive mode by opening a Terminal and running:

    pat -l ax25 interactive
  

• TX Delay, TX Tail, Persist, Slot time

  The AX.25 KISS protocol describes these options.

• Load Default AX25 Timers

  Clicking this button restores the timers to their default values.

• Edit pat Connection Aliases Button

  Clicking this button brings up a window that allows you to search for RMS gateway stations (the output of the pat rmslist command) and add them to pat's connection alias list. These aliases are available in a dropdown in the pat web interface Connection dialog to make it easy to select RMS gateway stations to connect to.

  pat has a restriction in that if you include a frequency in an connection alias, you must also run rigctld while running pat. Hamlib, which provides rigctld, is already installed in Nexus DR-X. If you don't already run rigctl, this configuration gui will configure rigctld to use a "dummy" rig to fool pat into thinking it's talking to your radio via rigctld. Note that when rigctld is used with a "dummy" radio, you must manually set your radio to the desired frequency.

Rig Control tab

Provides information about how pat uses rig control. A Manage Hamlib rigctld button is provided that will launch the rig control script.

ARDOP and pat gui

ardop_pat_gui.sh provides a GUI to configure the piardopc TNC (which implements ARDOP version 1) and pat to make a functional Winlink email client on Nexus DR-X. It also provides a monitor window that shows messages from both piardopc and pat.

If you make any changes in either of the Configure tabs, click Restart ARDOP and pat to activate the changes.

Configure ARDOP tab

• Audio Capture and Playback

  Select your audio device for capture (audio from the radio) and pl;ayback (audio to the radio). Use the guidance on the screen for what to select for the Nexus DR-X image. The script makes an attempt to find and present audio devices present on the Pi. For example, on ICOM radios like the 7100 and 73000 with built in sound cards that interface to the Pi via a USB cable, the plughw:CARD=CODEC,DEV=0 item is the correct choice for both capture and playback.

• PTT

  Push-to-Talk setting. Unless the radio uses CAT commands for PTT, the usual setting one of the GPIO selections per the guidance on the screen. You can select "rig control via pat" if you want pat to control PTT via rigctl. Your radio must be supported by Hamlib (which provides rig control) and be connected to the Pi via USB for this to work.

• ARDOP Port

  The TCP port piardopc listens on for commands from ARDOP clients like pat. Default is 8515.

• piardopc Arguments (OPTIONAL)

  Usually not needed. Any arguments you supply will be passed to piardopc. There is no error checking, so watch the monitor window for error messages from piardopc. These are the available arguments:

    -l path or --logdir path   		Path for log files
    -c device or --cat device  		Device to use for CAT Control
    -p device or --ptt device         	Device to use for PTT control using RTS
    -k string or --keystring string   	String (In HEX) to send to the radio to key PTT
    -u string or --unkeystring string 	String (In HEX) to send to the radio to unkeykey PTT
    -L use Left Channel of Soundcard in stereo mode
    -R use Right Channel of Soundcard in stereo mode
    CAT and RTS PTT can share the same port.
  

  Logs are helpful for debugging, but not needed for normal operation. If you don't specify the log file pat with -l path, logging will be disabled.

  If you provide -p device as an argument, it will override the PTT setting in the GUI.

Configure pat tab

Configures the pat Winlink email client. Clicking the Edit pat Connection Aliases button brings up a window that allows you to search for RMS gateway stations (the output of the pat rmslist command) and add them to pat's connection alias list. These aliases are available in a dropdown in the pat web interface Connection dialog to make it easy to select RMS gateway stations to connect to.

pat has a restriction in that if you include a frequency in an connection alias, you must also run rigctld while running pat. Hamlib, which provides rigctld, is already installed in Nexus DR-X. If you don't already run rigctl, this configuration gui will configure rigctld to use a "dummy" rig to fool pat into thinking it's talking to your radio via rigctld. Note that when rigctld is used with a "dummy" radio, you must manually set your radio to the desired frequency.

If you make any changes in either of the Configure tabs, click Save Settings & Restart ARDOP + pat to activate the changes.

• Call Sign, Winlink Password, Locator Code

  These should be self explanatory.

• Web Service Port

  The port on which pat will listen for traffic from the pat web interface. Default is 8049.

• Start pat web service when ARDOP starts

  Checking Start pat web service when ARDOP starts will start pat with the http server enabled. If this option is not checked, pat will not run at all. You can then run pat in interactive mode by opening a Terminal and running:

    pat -l ardop interactive
  

• Telnet Service Port

  The port on which pat will listen for telnet traffic. Default is 8774.

• Forced ARQ Bandwidth (Hz)

  According to ARDOP Overview, The bandwidth can be forced by server, forced by client or negotiated by the server and client. Enabling forced here makes pat, the ARDOP client, set the bandwidth. Default is disabled.

• Max ARQ Bandwidth

  According to ARDOP Overview, ARDOP is intended to operate in one of four audio bandwidths, 200 Hz, 500 Hz, 1000 Hz, and 2000 Hz. Default is 500 Hz.

• Beacon Interval (seconds)

  Supposedly transmits a beacon every x seconds. I can find no other information about this on the pat website. Default is 0 (disabled?).

• Enable CW ID

  Enables sending your call sign via CW. I can find no other information about this on the pat website. Default is TRUE.

• Edit pat Connection Aliases Button

  Clicking this button brings up a window that allows you to search for RMS gateway stations (the output of the pat rmslist command) and add them to pat's connection alias list. These aliases are available in a dropdown in the pat web interface Connection dialog to make it easy to select RMS gateway stations to connect to.

  pat has a restriction in that if you include a frequency in an connection alias, you must also run rigctld while running pat. Hamlib, which provides rigctld, is already installed in Nexus DR-X. If you don't already run rigctl, this configuration gui will configure rigctld to use a "dummy" rig to fool pat into thinking it's talking to your radio via rigctld. Note that when rigctld is used with a "dummy" radio, you must manually set your radio to the desired frequency.

Rig Control tab

Provides information about how pat uses rig control. A Manage Hamlib rigctld button is provided that will launch the rig control script.

Rig Control GUI

Provides a way to configure Hamlib's rigctld for use with pat and other applications.

TNC Script

tnc.sh launches Direwolf and, optionally, other related apps in different modes. The script will look for tnc.conf in the user's home directory. You can optionally override this behavior and specify the name and location of the configuration file using the '-c' parameter.

The script will set up and run Direwolf to operate in any one of these modes TNC: ax25, APRS Digipeater, APRS iGate, APRS Digipeater+iGate. It can also launch pat, ardop, pat+ax25, or pat+ardop provided those apps are also installed and configured.

TNC left TNC right Configuration Files

tnc-left.conf and tnc-right.conf configuration files are required by /usr/local/bin/tnc.sh script. They contain the configuration that tnc.sh needs in order to operate with Direwolf as an APRS Digitpeater, iGate, Digipeater+iGate, or ax25 TNC.

IMPORTANT: You must edit tnc-{left|right}.conf with your own settings before running tnc.sh for the first time.

tnc.sh will look for tnc.conf in the user's home folder. To use tnc.sh, you must make a symlink to the appropriate tnc configuration file for the left or right radio.

• For the left radio:

    cd ~
    ln -s tnc-left.conf tnc.conf
  

• For the right radio:

    cd ~
    ln -s tnc-right.conf tnc.conf
  

You can also specify the name and location of the configuration file using the '-c' parameter.

Trim Scripts

trim-fldigi-log.sh
trim-flmsg-log.sh
trim-flrig-log.sh
trim-fsq-audit.sh
trim-fsq-heard.sh

This collection of scripts trims the logs of various applications in the Fldigi family. They all take 1 argument: A date reference, for example: "10 days ago" or "1 hour ago". The script will delete log entries older than the date specified. These scripts are run whenever you launch Fldigi, Flrig and Flmsg from the Raspberry > Hamradio menu. You can change the timeframe of the trim by editing the .desktop. file. For example, this is the Exec entry in the /usr/local/share/applications/fldigi-left.desktop file:

Exec=sh -c '/usr/local/bin/trim-fldigi-log.sh "yesterday";PULSE_SINK=fepi-playback PULSE_SOURCE=fepi-capture fldigi --config-dir $HOME/.fldigi-left -title "Fldigi (Left Radio)" --flmsg-dir $HOME/.nbems-left'	

To change it to trim log entries older than 2 weeks ago rather than yesterday, the line would look like this:

Exec=sh -c '/usr/local/bin/trim-fldigi-log.sh "2 weeks ago";PULSE_SINK=fepi-playback PULSE_SOURCE=fepi-capture fldigi --config-dir $HOME/.fldigi-left -title "Fldigi (Left Radio)" --flmsg-dir $HOME/.nbems-left'	

Watchdog TNC Script

watchdog-tnc.sh runs via cron. It launches tnc.sh and restarts it automatically if it stops for some reason. It is intended for use when tnc.sh is run in one of the APRS modes. The script takes one argument, which it passes to tnc.sh as the "mode" argument. These are examples of entries you could use in crontab (only ONE can be used at one time):

# This one digipeats only - no internet
*/2 * * * * /usr/local/bin/watchdog-tnc.sh digi >/dev/null 2>&1

# This one digipeats and igates 
*/2 * * * * /usr/local/bin/watchdog-tnc.sh digiigate >/dev/null 2>&1

# This one igates only
*/2 * * * * /usr/local/bin/watchdog-tnc.sh igate >/dev/null 2>&1

Shutdown Button Script

shutdown_button.py monitors the shutdown button found on the DigiLink REV DS and Nexus DR-X boards. It reboots the Pi if the button is pressed more than 2 but less than 5 seconds, or shuts down the Pi if the button is pressed for more than 5 seconds.

The LED also pulses every 2 seconds. This is to support WB7FHC's hardware watchdog hat, which uses the GPIO output tied to this LED as a proof-of-life heartbeat for the board. If the heartbeat is stopped (if the Pi locks up, for example, or the script is stoppes) for some numer of seconds, the hardware watchdog hat removes and re-applies power to the Nexus DR-X buck converter.

Your Nexus DR-X image already has the systemd service file for the shutdown script installed and enabled. No further action is required to enable it, but for documentation purposes only, here's how to enable the service manually:

• As sudo, create a file called /etc/systemd/system/shutdown_button.service with the following text:

    [Unit]
    Description=GPIO shutdown button
    After=network.target
  
    [Service]
    Type=simple
    Restart=always
    RestartSec=1
    User=root
    ExecStart=/usr/bin/python3 /usr/local/bin/shutdown_button.py
  
    [Install]
    WantedBy=multi-user.target
  

• Run these commands in a Terminal to enable the service:

    sudo systemctl enable shutdown_button.service
    sudo systemctl start shutdown_button.service
  

• Run this command to disable the service

    sudo systemctl disable shutdown_button.service
  

Radio Monitor script

radio-monitor.py monitors the TX/RX status of your radios via the GPIO pins. The associated Hamradio menu item is in the radio-monitor.desktop file. By default, it monitors BCM GPIO pin 12 for the left radio and BCM GPIO pin 23 for the right radio PTT status. You can change these as well as the text color, and background color for TX and RX states from the command line. For options, run radio-monitor.py -h in Terminal to see this output:

usage: radio-monitor.py [-h] [-v] 
			[--left_gpio LEFT_GPIO]
			[--right_gpio RIGHT_GPIO]
			[--left_text_color {white,black,red,green,blue,cyan,yellow,magenta}]
			[--left_bg_rx_color {white,black,red,green,blue,cyan,yellow,magenta}]
			[--left_bg_tx_color {white,black,red,green,blue,cyan,yellow,magenta}]
			[--right_text_color {white,black,red,green,blue,cyan,yellow,magenta}]
			[--right_bg_rx_color {white,black,red,green,blue,cyan,yellow,magenta}]
			[--right_bg_tx_color {white,black,red,green,blue,cyan,yellow,magenta}]

TX/RX Status

optional arguments:
  -h, --help            show this help message and exit
  -v, --version         show program's version number and exit
  --left_gpio LEFT_GPIO
			Left radio PTT GPIO (BCM numbering) 
			(default: 12)
  --right_gpio RIGHT_GPIO
			Right radio PTT GPIO (BCM numbering) 
			(default: 23)
  --left_text_color {white,black,red,green,blue,cyan,yellow,magenta}
			Text color for left radio indicator 
			(default: yellow)
  --left_bg_rx_color {white,black,red,green,blue,cyan,yellow,magenta}
			Background color for left radio RX indicator 
			(default: green)
  --left_bg_tx_color {white,black,red,green,blue,cyan,yellow,magenta}
			Background color for left radio TX indicator 
			(default: blue)
  --right_text_color {white,black,red,green,blue,cyan,yellow,magenta}
			Text color for right radio indicator 
			(default: yellow)
  --right_bg_rx_color {white,black,red,green,blue,cyan,yellow,magenta}
			Background color for right radio RX indicator
			(default: green)
  --right_bg_tx_color {white,black,red,green,blue,cyan,yellow,magenta}
			Background color for right radio TX indicator
			(default: red)

To change the way the script runs when launched from the Hamradio menu:

• Click Raspberry > Hamradio, then right-click on Radio_PTT_Monitor

• Click Properties.

• Select the Desktop Entry tab.

  As an example, say you want to change the RX background color for the right radio to black and the TX background of the left radio to red. Change the contents of the Command: field to:

    /usr/local/bin/radio-monitor.py --right_bg_rx_color=black --left_bg_tx_color=red
  

• Click OK

Note that editing a menu item in this way will create a new .desktop file in your $HOME/.local/share/applications folder with the same name as the system .desktop file in /usr/local/share/applications folder. Your local menu file will take precedence over the system file.

Piano Script example

pianoX.sh.example is stored in your home folder and contains some ideas for using the piano switch feature of the Nexus DR-X boards. Copy this file to your own script (pianoX.sh where X is 1,2,3,4 or some combination of those numbers) and edit as desired to make your Pi run certain scripts or applications at boot time.

Desktop Template Files

These files are stored in /usr/local/share/applications and are used as templates for application desktop files. They are used by the Name Your Radio script to change the radio names as they appear in the Hamradio menu.

Edit Desktop Text script

edit-desktop.sh allows you to edit the default Nexus DR-X desktop background, which was introduced in Nexus DR-X version 20191214.

If your image is older than 20191214 and you want to install the customizable Nexus desktop background, you must do run these commands in the Terminal before you can run the new 'Edit Desktop Background Text’ script (NOTE: This will REPLACE your current desktop background):

cp /usr/local/src/nexus/desktop-items-0.conf $HOME/.config/pcmanfm/LXDE-pi/
pcmanfm --reconfigure

After you start the script (Raspberry > Preferences > Edit Desktop Background Text), enter the text you want to display and optionally check the box to show your Pi's host name, then click OK. The script won't close until you Cancel, so click Cancel when you're satisfied with your new desktop.

FSQ Search script

This script monitors the fsq_audit_log.text file and optionally runs a user specified script upon locating a string provided by the user as search criteria. It also prints (with an optional timestamp) messages matching the user's search string to stdout. This script has no GUI and is designed to run in a terminal or as an autostart app in Fldigi. Only one instance of the script runs at a time and it monitors messages for both the left and right radios simultaneously. It will kill itself if no more instances of Fldigi are running.

For usage information, run this command in the Terminal:

fsq_search.sh -h

VNC Server Activity script

This script extracts Connection events for VNC server activity occuring in the past 24 hours and emails results via patmail.sh and pat.

• Prerequisites
  • pat and patmail.sh must be installed.
  • pat must be configured.

Before running the script, you must specify the recipient's email address(es) by editing the script. The destination email addresses are assigned to the MAILTO variable.

You can execute this script automatically via cron. The following example will run it once per day and report on the previous 24-hour's VNC connections. This example will run at 3 minutes after midnight every day:

3 0 * * *   /usr/local/bin/vnc-server-activity.sh 2>&1 >/dev/null

USB Device Manager script

usb_control.py allows you to "virtually" plug/unplug most USB devices remotely by using the bind and unbind feature in Linux. This can be handy when you need to remotely re-mount a USB drive or remove/insert a USB-serial or other USB adapter.

The script can be run in 2 ways: From the command line or via a GUI. If no arguments are supplied, the script attempts to start in GUI mode.

In GUI mode, the script will list the USB devices it finds. It will not list USB hubs, but it will list devices connected to hubs. Clicking on a device in the list toggles that device's state. The states are Enabled (bound) or Disabled (unbound). It will detect when devices are physically inserted or removed and automatically update the device list.

If you run usb_control.py from the command line with the -b or -u options, the script will search for a device containing the string you supply. It will search the USB ID and the Tag (product description) for your string. If found, it'll enable (bind) if you supplied -b or disable (unbind) if you supplied -u. If you run it with the -l option, it will list the non-hub USB devices it finds.

Run usb_control.py -h to see the command line options:

usage: usb_control.py [-h] [-v] [-l] [-b STRING] [-u STRING]

USB Device Control

optional arguments:
  -h, --help            show this help message and exit
  -v, --version         show program's version number and exit
  -l, --list            List available USB devices
  -b STRING, --bind STRING
			bind (enable) a usb device containing STRING (case-
			insensitive) in 'lsusb' output ID or Tag fields
  -u STRING, --unbind STRING
			unbind (disable) a usb device containing STRING (case-
			insensitive) in 'lsusb' output ID or Tag fields