The Hawk's operation centres around the concept of a "Task" - which is a selection of actions, performed on a schedule. Up to two tasks can be configured, with up to three actions each.
Broadly, we can think of the tasks as the time interval, and the actions of the sensor readings we take.
If we don't configure a task, the Hawk by default will do nothing but heartbeat once daily.
We may also need to configure our sensors separately, on other parameter tabs to ensure the setup is correct for when the task runs.
There are two tasks as there may be some sensors we wish to sample frequently, and others less frequently. E.g. sample temp every 10 min, tank level every 2hrs.
- Period Unit + Schedule Period
- Set how often the task (and actions) occur
- Upload Multiplier
- Upload every N tasks
- GPS Multiplier
- If the asset is stationary, or moves infrequently, we might disable GPS completely (set to 0) - or set the multiplier to a large number so fixes occur less often. This conserves energy and extends battery life
- Start/End Period
- We might only want to run the task during a certain time (i.e. during day). Or we might want it to run every 10 min during 6am -> 6pm, and hourly outside that - in which case we can set up 2 tasks to achieve this.
- Actions are typically which sensor readings we want to take - but these include:
Example Task Configurations
Some examples are given below. These serve to illustrate how to configure tasks, generally we need to configure additional parameters specific to the sensor type and individual sensor.
- Run the task (take a sensor reading) every 10 min
- Upload every single task - so we sample and upload every 10 min
- Run I2C Action 1
We configure I2C action 1 to sample the sensor type we have connected - DM Ambient (Temp/Hum) Sensor
- Read value every 10 min
- We upload every 6 tasks - so every 6 x 10 min = hourly
- GPS Multiplier = 0 to disable GPS - the Hawk is mounted in a stationary location so we don't care about GPS position
- Sample the 4-20mA sensor
For the 4-20mA sensor, we configure a power on delay and which analogue the value should be placed in the Hawk's payload.
We set the upload multiplier to 0 to not upload due to this task - the readings will be logged and uploaded together with the task 2 upload.
Task 2 the soil moisture reading (via SDI-12 probe) hourly, and upload.
1. Set timezone
2. Run task 1 (15 min sample + upload from 0600 → 1800
3. Run task 2 (6 hour sample + upload) from 1800 → 0600
It may be useful to know how the Hawk processes tasks. When a task runs, the following occurs:
- Start Task
- GPS started if requested
- Action 1
- Action 2
- Action 3
- Action 4
- Wait for GPS to finish
- Pack readings + results up into record and log
- Check Analog thresholds
- Upload if necessary