Pysense

Components

• Any Pycom board that supports the connection through Wifi
• Pycom Pysense board
• Micro USB to USB cable

Setup Your Development Environment

We'll be using Atom as our development environment. You can download the latest version from here.

Once you've got it setup, install the Pymakr plugin. Follow the steps in this tutorial to get it setup.

Connect to the Board

• Before connecting your module to the Pysense board, you should update the firmware on the Pysense. Instructions on how to do this can be found here Look for the reset button on the module (located at a corner of the board, next to the LED)
• Locate the USB connector on the Pysense
• Insert the module on the Pysense with the reset button pointing towards the USB connector. It should firmly click into place and the pins should now no longer be visible.
• Connect the USB port on Pysense board to the USB port on the computer

Get Device Name

Once you've got it connected to your computer, get the name of your device using one of the following steps:

Linux and Mac OS X

• Download and install the FTDI drivers from here. Select the appropriate version for your operating system and architecture.
• Open a terminal window and run the command ls /dev/tty*
• Look for a device with the name that begins with /dev/tty e.g. /dev/tty.usbmodemPy343431 on MAC or /dev/ttyUSB0/dev/ttyACM0 on Linux.

Windows

• Download and install the FTDI drivers from here. Select the appropriate version for your operating system and architecture.
• Open the Windows start menu and search for 'Device Manager'
• The COM port for the Pycom device will be listed as 'USB Serial Device' or something similar
• Keep note of the COM port (e.g. COM4)

Setup Your Project

• Create a new folder for your project. I'm going to call mine pycom-pysense.
• In Atom, go to File > New Window to open a new window.
• Add your newly created folder by clicking File > Add Project Folder and navigating to it.
• If the Pymakr plugin is not open at the bottom of your Atom window, click on the arrow on the right hand side to open it.
• Select Settings > Project Settings. In the address field replace the value with the device name from the step above e.g. /dev/tty.usbmodemPy343431 (Mac OS X), COM3 (Windows), /dev/ttyACM0 (Linux) then save the file.

Add required Libraries

• Right click on the folder name in Atom and click Add Folder. Enter lib as the folder name.
• Right click on the lib folder and click New File. Enter urequests.py as the file name.
• Click on the file then copy and paste the code from here into that file then save it.
• For Pysense, additional libraries must also be added to the lib folder, these can be found here

Publish an Event

• In Atom, right click on your project and click New File. Enter boot.py as the filename.
• Copy and paste the code below into the file.

from machine import UART

import machine

import os

​

uart = UART(0, baudrate=115200)

os.dupterm(uart)

​

machine.main('main.py')

• Right click on your project and click New File. Enter main.py as the filename.
• Copy and paste the code below into the file.

from network import WLAN

from pysense import Pysense

from SI7006A20 import SI7006A20

import urequests as requests

import socket

import time

​

py = Pysense()

si = SI7006A20(py)

​

# Your WiFi network credentials

WIFI_SSID = 'your-wifi-ssid'

WIFI_KEY = 'your-wifi-password'

​

# Get this from the Wia dashboard

DEVICE_SECRET_KEY = 'your-wifi-ssid'

​

url = "https://api.wia.io/v1/events"

headers = { "Authorization": "Bearer " + DEVICE_SECRET_KEY, "Content-Type": "application/json" }

​

wlan = WLAN(mode=WLAN.STA)

nets = wlan.scan()

​

# Connect to the WiFi network

for net in nets:

    if net.ssid == WIFI_SSID:

        print('Network found!')

        wlan.connect(net.ssid, auth=(net.sec, WIFI_KEY), timeout=5000)

        print('Connecting...')

        while not wlan.isconnected():

             machine.idle() # save power while waiting

        print('WLAN connection succeeded!')

        break

​

​

# Post an Event to the Wia cloud

def post_event(name, data):

    try:

        json_data = { "name": name, "data": data }

        print str(json_data)

        if json_data is not None:

            req = requests.post(url=url, headers=headers, json=json_data)

            return req.json()

        else:

            pass

    except:

        pass

​

# main loop

while True:

    # Takes the temperature from the Pysense expansion board

    post_event("hello-wia", "")

    time.sleep(10)

Replace the following values of the following variables:

• WIFI_SSID with your WiFi network name.
• WIFI_KEY with your WiFi network password.
• DEVICE_SECRET_KEY with your device secret key from earlier (the one that begins with d_sk).

Your folder structure should now look like this:

• lib
• urequests.py
• LIS2HH12.py
• LTR329ALS01.py
• MPL3115A2.py
• SI7006A20.py
• pycoproc.py
• pysense.py
• boot.py
• main.py

Click Upload in the Pymakr plugin at the bottom of your window in Atom and send the code to your Pycom board. Now go to the Wia dashboard and you should see it appearing in your device overview.

Now go to your device in the Wia dashboard and you should see the data appearing in the debugger.