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Periodic Sensor

How to run it

Before running this example, you have launch the docker container. You can find the instructions in the Docker page of the documentation.

When you are in the docker container, you have to go to the messy directory:

cd /messy/messy/

Then we can run python:

python3 messy.py -f codegen/pulp_open.json -a /messy/examples/periodic-sensor
The parameters are:

  1. -f is the file name of the chosen system configuration
  2. -a is the path of the folder of the application

Explanation

This example, as the name suggest, is a simple example that periodically writes a value to the sensor memory. This example is useful to understand how to interact with the sensor memory and how the flow of a write operation works. For more information about the write request, please refer to the Communication Example page.

By adding some print statements inside the functional model of the sensor, we can see how the memory of the sensor is updated, each time a write occurs.

[ITER 0/2880] 0.00 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 2
[ITER 1/2880] 0.01 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 4
[ITER 2/2880] 0.02 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 6
[ITER 3/2880] 0.02 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 8
[ITER 4/2880] 0.03 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 10
[ITER 5/2880] 0.04 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 12
[ITER 6/2880] 0.05 Hours Elapsed
[SENSOR] Writing data to register memory at address 0
[SENSOR] Data written: 14
....

If we let this example run for enough time and inspect the messy_trace.log we can see the battery level decreasing over time. This is because the sensor is periodically writing to the memory, which in turn is consuming energy from the battery. This is a simple example to show how the sensor memory can be accessed and how the sensor can be used to interact with the system.