Note: to be able to compile this application you need to add the right board file to your Arduino IDE.
Go to File, Preferences and set the following URL for the additional board files:
http://downloads.sodaq.net/package_sodaq_samd_index.json
After compiling the source code and uploading it to the board you will be able to configure the board through a menu.
Just open the Arduino Serial Monitor (at 9600 baud) and you will get this menu:
** SodaqOne Universal Tracker v2 - 4.1 **
LoRa HWEUI: 0004A30B00198185
-> CPU reset by Software [64]
Commands:
Reset DevAddr / DevEUI to the Hardware EUI (EUI):
Commit Settings (CS):
Settings:
GPS
GPS (OFF=0 / ON=1) (gps=): 1
Fix Interval (min) (fi=): 15
Alt. Fix Interval (min) (afi=): 0
Alt. Fix From (HH) (affh=): 0
Alt. Fix From (MM) (affm=): 0
Alt. Fix To (HH) (afth=): 0
Alt. Fix To (MM) (aftm=): 0
GPS Fix Timeout (sec) (gft=): 120
Minimum sat count (sat=): 4
Num Coords to Upload (num=): 1
On-the-move Functionality
Acceleration% (100% = 8g) (acc=): 0
Acceleration Duration (acd=): 0
Fix Interval (min) (acf=): 1
Timeout (min) (act=): 10
LoRa
OTAA Mode (OFF=0 / ON=1) (otaa=): 0
Retry conn. (OFF=0 / ON=1) (retry=): 0
ADR (OFF=0 / ON=1) (adr=): 1
ACK (OFF=0 / ON=1) (ack=): 0
Spreading Factor (sf=): 7
Output Index (pwr=): 1
Lora Port (lprt=): 1
DevAddr / DevEUI (dev=): 0004A30B00198185
AppSKey / AppEUI (app=): 00000000000000000000000000000000
NWSKey / AppKey (key=): 00000000000000000000000000000000
Repeat Count (rep=): 0
Misc
Temperature Sensor Offset (temp=): 20
Status LED (OFF=0 / ON=1) (led=): 0
Debug (OFF=0 / ON=1) (dbg=): 0
Enter command:
Entering commands is just a matter of typing the command as given in brackets with the right value. For example:
fi=5
Will set the time between the GPS fixes to 5 minutes. Setting fi=0 will disable the default fix interval.
After the startup the device by default willt be in deep sleep mode. In sleep it uses less than 50 uA. Using the RTC Timers it will wake up at the set intervals.
The application is based on the RTCTimer library. At startup the application tries to obtain a GPS fix until timeout. If no fix can be obtained initially the location will be set to 0,0. Once the first fix is obtained the RTC will be set and that fix location will be kept until the next proper fix.
There is a system watchdog running in case the application hangs it will be restarted by the watchdog. (See library Sodaq_wdt)
As seen in the configuration menu we allow for two different schedules for GPS fixes based on UTC time. The default could for instance be that we want a GPS fix every 30 minutes during the night, but during the day we want a fix every 5 minutes. In that case we configure the default to be 30 minutes, but the optional fix timer to be 5 minutes from 06:00 UTC to 18:00 UTC.
The RTC library allows for two of such timers. In case the second Fix interval is set to 0 the second timer is simply ignored.
After a GPS fix is obtained with at least 'Minimum sat count' satellites (or the timeout reached) a LoRa packet will be sent. In case of timeout without obtaining enough satellites, the best GPS fix found (if any) is used.
For redundancy we could configure a repeat count. The value of the repeat count tells us to send the Lora frame an additional number of times (default 0) for redundancy.
The Lora frame contains the following data. The minimum frame size is 21 bytes, the maximum frame size 51 bytes, depending on the number of coordinates we have configured to be sent.
The LoRa communication only starts if the keys are not 0 (0 is the default) If 'Retry conn.' is on, then in case the connection to the network is not successful (useful for OTAA), the application will retry to connect the next time there is a pending transmission.
The on-board accelerometer provides temperature delta with 1 degree Celsius resolution. It is not factory calibrated so the offset needs to be set in the application (command "temp" or it can be hardcoded in the code) for each board.
The firmware supports, except for the default and alternative fix intervals, a third fix interval that is dependent to movement: if the acceleration on any axis goes over (or below in the case of a negative axis) the acceleration set in Acceleration% parameter for over the set duration, the on-the-move fix interval becomes active until "Timeout" minutes have passed since the last movement detected.
| Description | Length |
|---|---|
| Epoch Timestamp | uint32 (4) |
| Battery voltage (between 3 and 4.5 V) | uint8 (1) |
| Board Temperature (degrees celcius) | int8 (1) |
| Lat | int32 (4) |
| Long | int32 (4) |
| Altitude (MSL in meters) | int16 (2) |
| Speed (SOG * 100 km/h) | uint16 (2) |
| Course (COG) | uint8 (1) |
| Number of satellites | uint8 (1) |
| Time to fix (seconds, FF = no fix, in that case the above position is the last known) | uint8 (1) |
| Plus 0 - 3 of the following 10 bytes: | |
| Previous fix (seconds ago, FFFF means longer than) | uint16 (2) |
| Lat | long (4) |
| Long | long(4) |
You can send the following configuration parameters back to the device (as part as the LoRaWAN class A communication protocol)
| Description | Length |
|---|---|
| Fix Interval default | uint16 (2) |
| Fix Interval alternate | uint16 (2) |
| From (EPOCH) | long (4) |
| To (EPOCH) | long (4) |
| GPS fix timeout in seconds | uint16 (2) |
Copyright (c) 2016, SODAQ All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
-
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
-
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
-
Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.