The relays string is made of 6 booleans that indicate the relay setting: 0 = ON, 1 = OFF, 2 = REBOOT. The user can control the state of the sensor by changing the appropriate boolean in the array. Example: 011011 means l2 is ON, l3 is OFF, L1 iridium is OFF, 4G modem is ON, pumps are OFF, VHF is OFF.

Commands are sent from operators to the vehicle. Replies viceversa.
Commands are written in red. Reference: https://github.com/LSTS/dune/wiki/Text-Commands

Periodical Status Reports: periodical reports from the vehicle.

(R) 13:29:16/63.872886,8.640461/b:127/c:78/s:0.00/sat:8/pp:15/cp:17/s:M/001011

meaning: (R)=report/UTC time/latitude(deg),longitude(deg)/b=battery voltage/c=COG/s=SOG/sat=GPS satellites in view/pp=produced power (from solar panels)/cp=consumed power (from system+thruster)/s=status (M:maneuvering, S:service, C:calibration, E:error)/relays.
The frequency of reports can be set via Iridium by sending this message:
<color red>reports seconds</color>: seconds is the amount of seconds between two reports.

Navigation Commands are used to send new navigation plans, retrieve telemetry and statistics, mission status.

1. <color red>info</color>: retrieve information about plan being executed
   replies:
   
   1. Vehicle is ready. : vehicle is ready to execute its first plan.
   2. Initializing <plan_id>. : vehicle is in calibration mode, starting a plan.
   3. Executing <plan_id> / <man_id>. ETA: <eta in seconds> (<progress>%) : Vehicle is currently executing a plan.
   4. Finished <plan_id> : vehicle has finished executing a plan successfully.
   5. Failed to exec <plan_id>: <reason> : vehicle has failed to execute its plan.
2. <color red>navstat</color>: retrieve navigation information
   reply:
   

   (NAV) 2020-06-23 13:28:06/63.8728 8.6404/C:69/dC:-20/r:-57/th:0/S:0.0/aws:0.7/awd:118

   meaning: (NAV)=navigation report/UTC date&time/latitude(deg),longitude(deg)/C=COG/dC=desired COG/r=rudder angle/th=thruster actuation/S=SOG/aws=absolute wind speed/awd=absolute wind direction.

3. <color red>abort</color>: this command aborts the execution of any ongoing plan and receives no arguments.
4. <color red>errors</color>: retrieve a simple vehicle diagnostic
   replies: Vehicle has no reported errors. or Errors: <entities_in_error> listing all entities that present errors.
5. <color red>start plan_ID</color>: order execution of a plan already in the Plan Database of the vehicle. It receives, as its sole argument the name of the plan to be executed.
   reply: Started execution of plan_ID.
6. <color red>force plan_ID</color>: order execution of a plan ignoring any errors.
   reply: Started execution of plan_ID ignoring errors.
7. <color red>resume plan_ID GoTo_number</color>: order execution of a plan, starting from a specific maneuver id. It will generate a new plan that has the given maneuver ID as the starting maneuver and then will proceed to execute it. It will create a new plan named plan_ID-Goto_number that starts in maneuver Goto_number and will execute the plan.
8. <color red>go lat=<latitude>;lon=<longitude>;speed=<speed></color>: commands the vehicle to go to a given waypoint in DEGREES (using a Goto maneuver).
9. <color red>fence <latitude>,<longitude>;<latitude>,<longitude>;…</color>: creates a polygon (geofence) using the <latitude>,<longitude> (in DEGREES) list as vertices; when the USV is outside the polygon, a warning is raised and an Iridium message is sent.
10. <color red>colav on/off</color>: turns anti-collision system on.
11. <color red>gains p i d</color>: sets new gains for the course/heading autopilot.

Hardware Commands are used to send new navigation plans, retrieve telemetry and statistics, mission status.

1. <color red>cr6 relays</color>: where relays is the string of booleans indicated above. This command enables/disables the solid-state relays.
   reply: New CR6 settings applied.
2. <color red>on relay/sensor</color>: enables a specific relay - turns ON a specific sensor as indicated in the table above. Example on vhf turns ON the VHF radio.
   reply: VHF is turning on.
3. <color red>off relay/sensor</color>: disables specific relay - turns OFF a specific sensor as indicated in the table above. Example off modem turns OFF the 4G/LTE Modem.
4. <color red>restart relay/sensor</color>: toggles off and on a specific relay - restarts a specific sensor as indicated in the table above. Example restart modem restarts the 4G/LTE Modem.
5. <color red>reboot</color>: Reboot the system remotely. It can be used to reboot just DUNE, the main CPU or auxiliary CPU.
   
   1. reboot: Reboots the main CPU.
   2. reboot aux: Reboots the auxiliary CPU.
   3. reboot dune: Reboots DUNE without rebooting the CPU.
6. <color red>camera</color>: Triggers the onboard camera
   
   1. camera on: Starts live broadcast.
   2. camera off: Stops live broadcast and deactivates the camera until further notice; if routines are running, they are disabled.
   3. camera frame: Captures and stores one frame.
   4. camera video 20: Records one video of 20 seconds.
   5. camera frame-p 300: Captures one frame every 300 seconds.
   6. camera video-p 300 20: Records one video every 300 seconds of 20 seconds length.

The following set of commands is able to control the Scientific Payload.

- <color red>sensor sensor_ID on_off samp_duration samp_interval</color>: where sensor_ID is the sensor ID; on_off determines if the sensor has to be turned ON or OFF; samp_duration determines for how long (seconds) the sensor collects data; samp_interval indicates the seconds between two consecutive samplings (sensor is turned OFF between them)
replies:

1. L3 is OFF, turn on first. : if the payload computer is OFF.
2. sensor_name is already ON : if the sensor to be turned ON is already ON.
3. sensor_name is already OFF : if the sensor to be turned OFF is already OFF.
4. sensor_name actions. otherwise (sensor is OFF and you want to turn it ON or viceversa).
5. Examples: <color red>sensor ctd 0 60 120</color> will turn ON the CTD at regular intervals of 120s and collect CTD data for 60s; <color red>sensor opt 0 0 0</color> will turn ON the Optode 4835 and sample indefinitely; <color red>sensor eco 1 0 0</color> will turn OFF the ECOPuck Triplet indefinitely.

- <color red>sensors</color> + <color red>sensor_ID on_off samp_duration samp_interval</color> for each sensor: unique long message to control all sensors with one Iridium message only. - <color red>sensor_name report</color>: where sensor_name is the full sensor name.

1. <color red>ecopuck report</color> will reply
   

   (ECO) 2020/06/23 09:00:21/63.8728 8.6404/FDOM:0.1832/TU:0.0912/CHLA:0.1898

   meaning: (ECO)=sensor_id/UTC date-time/latitude(deg),longitude(deg)/FDOM=fluorescent dissolved organic matter/TU=turbidity/CHLA=chlorophyll-a.
   

2. <color red>ctd report</color> will reply
   

   (CTD) 2020/06/23 09:37:49/63.8728 8.6404/S:0.29/C:0.04/T:15.80/SS:-1.00/D:0.05

   meaning: (CTD)=sensor_id/UTC date-time/latitude(deg),longitude(deg)/S=salinity/C=conductivity/T=water temperature/SS=sound speed/D=sensor depth.
   

3. <color red>optode report</color> will reply
   

   (OPT) 2020/06/23 08:51:44/63.8728 8.6404/T:18.40/AS:98.87/DOX:289.87

   meaning: (OPT)=sensor_id/UTC date-time/latitude(deg),longitude(deg)/T=water temperature/AS=air saturation/DOX=dissolved oxygen.
   

4. <color red>tblive report</color> will reply
   

   (TBL) 2020/06/23 13:00:10/63.8728 8.6404/SN:1000037/T:0.00/ANL:9/PNL:14/RLF:69/RMA:4

   meaning: (TBL)=sensor_id/UTC date-time/latitude(deg),longitude(deg)/SN=sensor serial number/T=water temperature/ANL=average noise level/PNL=peak noise level/RLF=receiver listening frequency/RMA=receiver memory address.
   

5. <color red>ecopar report</color> will reply
   

   (PAR) 2020-07-01 18:01:16/63.8787 8.6482/PAR:302.03

   meaning: (PAR)=sensor_id/UTC date-time/latitude(deg),longitude(deg)/PAR=Photosynthetically Active Radiation value.
   

6. <color red>radiation report</color> will reply
   

   (RAD) 64.1658 8.4496/2020-07-02 10:01:41/PAR:831.52/2020-07-02 10:01:47/FDOM:1.28/TU:0.06/CHLA:0.13

   meaning: (RAD)=message_id/PAR sensor UTC date-time/latitude(deg),longitude(deg)/PAR=Photosynthetically Active Radiation value/ECOPUCK sensor UTC date-time/FDOM=fluorescent dissolved organic matter/TU=turbidity/CHLA=chlorophyll-a.
   

7. <color red>ADCP depth</color> will reply
   

   (ADCP) 2020-07-02 10:01:41/64.1658 8.4496/DP:7.5/S:1.4/D:64.4

   meaning: (ADCP)=message_id/UTC date-time/latitude(deg),longitude(deg)/DP=sea current depth/S=sea current speed/D=sea current direction in degrees (NED).