Pycom WiFi revisit

So I gave it rest after my initial foray into messing with the Pycom device I got back to it.  Updated Atom, updated Pymakr plugin – still need to update firmware.  More on that later.  I found the issue with my USB serial connection woes…turns out (for whatever reason, my TX jumper was disconnected.  The pretty much makes serial connection flakey at best.  Jumper in place and board communication is going well.

WiPy 2.0 and Atom

Yup, dumbass moment with pycom.

Installing Gradle on OSX via HomeBrew

Recent selenium project required use of Gradle.  Quickest way to install was via HomeBrew.  No rocket science but I find if I don’t write this stuff down I lose it quickly.

Install HomeBrew if you don’t have it installed already: goto

[code language=”bash” gutter=”false”]/usr/bin/ruby -e "$(curl -fsSL"

Use HomeBrew to install gradle

[code language=”bash” gutter=”false”] brew install gradle [/code]

Jenkins Install on AWS

Stolen from answer 1 –

sudo yum update
sudo wget -O /etc/yum.repos.d/jenkins.repo
sudo rpm --import
sudo yum install jenkins
service jenkins start
sudo service jenkins start
sudo chkconfig jenkins on

Jenkins will be used to build/deploy ruby on rails – install Ruby on Rails as prescribed in previous post: Rails on AWS



Ruby On Rails – AWS Linux

I have been working on setting up a Ruby on Rails project and using Amazon Web Services (AWS) to host it.  AWS EC2 instance out of the box of course is not setup to run rails.  After much trial and error I have narrowed down the setup process as listed below.

1 – Setup AWS EC2 Instance (your milage may vary – Assume you have setup EC2 instance before)

I used the following:
AMI – Amazon Linux AMI 2016.03.1 (HVM), SSD Volume Type – ami-f5f41398
Instance Type: General purpose  t2.medium

2 – Setup Rails Environment

Connect to EC2 Instance (ssh via terminal)

ssh -i "****.pem"
Always a good practice on new installs

$ sudo yum update

Install rvm for Ruby Version Management

$ gpg2 --keyserver hkp:// --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3
$ curl -L | bash -s stable
$ source ~/.profile 

Install zlib-devel
$ sudo yum install zlib-devel (don't exactly remember why this is needed - might be application specific)

Install openssl
$ rvm pkg install openssl
$ rvm reinstall 2.0.0 --with-openssl-dir=/usr/local/rvm/usr (ruby version up for debate)

my ruby project uses bundler - install it
$ gem install bundler

my application also require javascript
$ sudo yum install nodejs npm --enablerepo=epel

install git
$ sudo yum install git
$ git clone
$ cd yourrepo

run bundle install (again, my app uses it - your app may have other install steps
$ bundle install
$ rails s
You should see something like: varies depending on application server=> Booting WEBrick

=> Rails 3.2.12 application starting in development on
=> Call with -d to detach
=> Ctrl-C to shutdown server
Connecting to database specified by database.yml
[2016-05-24 13:56:28] INFO  WEBrick 1.3.1
[2016-05-24 13:56:28] INFO  ruby 2.0.0 (2015-12-16) [x86_64-linux]
[2016-05-24 13:56:28] INFO  WEBrick::HTTPServer#start: pid=27261 port=3000


Plotly via Python API

Spent some time working with the Plotly Python API.  Able to read my data logger files and upload to a plot with ease. Will need to comment code better I know…just started playing with it and wanted to share. Upload all environmental data and if the additional “Annotation” field exist add that to the plot as well.

More Info at: Plotly Python API

import plotly.plotly as py
from plotly.graph_objs import *
myname = 'plotlyid'
mykey = "plotlykey"
x1 =[]
y1 =[]
y2 =[]
y3 =[]
MyAnnotation = []
f = open("LOGGER26.CSV",'r')
#f = open("smallset.csv",'r')
for lines in f:
	data = lines.split(',')
	if len(data)==5:
		print data[4]
		Annotation = {'x':data[0],'y':data[1],'text':data[4] + data[0],'xref':'x','yref':'y','showarrow':True,'arrowhead':7,'bgcolor':'red'}
# (2) Make dictionary linking x and y coordinate lists to 'x' and 'y' keys
#     (mandatory in plotly v.1.0.8 and up)
layout = Layout(
    	domain=[0, 0.8],
        position = .9
trace1 = dict(x=x1,y=y1, name='Light')
trace2 = dict(x=x1,y=y2, name= 'Barometric',yaxis='y2')
trace3 = dict(x=x1,y=y3, name='Temp',yaxis='y3')
# (3) Make list of 1 trace, to be sent to Plotly
#     (mandatory in 1.0.8 and up)
data = [trace1,trace2,trace3]
fig = Figure(data=data,layout=layout)
plot_url = py.plot(fig, filename='MyEnvi')

Short data file snippet:

2014-6-10 19:19:48,508,996.00,24.94
2014-6-10 19:19:49,508,995.95,24.94
2014-6-10 19:19:50,508,995.99,24.94
2014-6-10 19:19:51,508,995.95,24.92
2014-6-10 19:19:53,507,995.93,24.92,Migraine Severe
2014-6-10 19:19:54,507,995.99,24.94
2014-6-10 19:19:55,507,995.96,24.94
2014-6-10 19:19:56,507,996.00,24.92
2014-6-10 19:19:57,507,995.98,24.94
2014-6-10 19:19:58,507,995.97,24.92
2014-6-10 19:19:59,507,995.92,24.92
2014-6-10 19:20:0,507,995.92,24.92

Next steps: Create a way to add the annotation to the data file on the Arduino.

Using with Adafruit Data Logging Shield

I have played with a few IOT type services for showing off data collected and or sent from Arduino (and other micro controller devices) and have settled on for now.

I have used ThingSpeak and Xively as well but found Plotly worked better for importing from the data logger disk than the others. Xively appear to be more “live update” oriented and not as well geared for file upload of large data sets. Graph from Arduino Barometric and Light Project

Arduino, Ethernet Shield, Node.js and AWS OpsWorks

After going though a lot of the great examples I wanted to dive into connecting the Arduino to the internet and figure out a way to push sensor data to the web for later consumption. Thanks to Remote logging with Arduino and Node.js at FRENKI.NET I was able to get the info I needed to setup a simple data collector application.

[code language=”cpp”]
//Sending one Analog Value to a Node.js server
//Used AWS OpsWorks and created basic Stack to deploy a node.js instance
//Stolen from FRENKI.NET


byte arduinoMac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
// desired IP for Arduino
IPAddress arduinoIP(192, 168, 1, 100);
// port of Arduino
unsigned int arduinoPort = 8080;

// IP of node.js server setup to recieve the data
IPAddress receiverIP(00, 00, 00, 00);
// Port on node.js server that is listening to UDP traffic
unsigned int receiverPort = 7777;

EthernetUDP Udp;

int sensorPin = A4; // Choose whatever sensor pin you would like to use
int sensorValue;

void setup() {
Ethernet.begin(arduinoMac,arduinoIP); //Initialize Ethernet UDP and Serial port

void loop() {
sensorValue = analogRead(sensorPin); // Read sensor value and store in sensorValue
byte valueInBytes[2] = {lowByte(sensorValue), highByte(sensorValue)}; //convert it to a byte array for the UDP Transfer
// Debug info for figuring out how byte array works
Serial.print("Low: ");
Serial.print("High: ");

// Send UDP Packet to node.js server
Udp.beginPacket(receiverIP, receiverPort); //start udp packet
Udp.write(valueInBytes, 2); //write sensor data to udp packet
Udp.endPacket(); // end packet
// Repeat every 5 seconds

node code:

Here is a snippet of node.js code used to receive the Arduino data. I used a simple AWS OpsWorks Deployment of an node.js instance. Add the following code to a file…arduindocollect.js and then run #node arduinocollect.js…


var dgram = require("dgram");
var server = dgram.createSocket("udp4");
var fs = require(‘fs’);

var crlf = new Buffer(2);
crlf[0] = 0xD; //CR – Carriage return character
crlf[1] = 0xA; //LF – Line feed character

server.on("message", function (msg, rinfo) { //every time new data arrives do this:
console.log("server got: " + msg.readUInt16LE(0) + " from " + rinfo.address + ":" + rinfo.port); // you can comment this line out
fs.appendFile(‘mydata.txt’, msg.readUInt16LE(0) + crlf, encoding=’utf8′);//write the value to file and add CRLF for line break

server.on("listening", function () {
var address = server.address();
console.log("server listening " + address.address + ":" + address.port);

server.bind(7777); //listen to udp traffic on port 7777


AWS – Make sure you update the Security Group to allow UDP on 7777 or whatever UDP Port you decide to use.