The idea behind IFTTT is tthat when an event occurs on one application or site it can trigger another application or event. There are [...]]]> Following on from a previous post describing the scrolling message display, I’m adding a few notes on how to use it with a service called If this then that (ifttt.com).

The idea behind IFTTT is tthat when an event occurs on one application or site it can trigger another application or event. There are a number of channels including Google Calendar, date and time, weather, Facebook, Twitter, Foursquare, Dropbox, Google Drive, Skydrive, RSS amongst others and interestingly SMS.

It is the ability to send SMS when a certain event occurs that can create messages for the scrolling message display. For example I have created recipes for:

• Send SMS when I checkin with Foursquare, showing my location and date/time
• Send SMS when an event in my Google Calendar is to start
• Send SMS with daily summary of weather, days high/low etc
• Send SMS if tomorrow is to be cold or rainy
• Send SMS when new mail recieved in GMail inbox

Other ideas could be to send a message when trains are delayed by using the RSS feed, to send a message when someone tags you in a photo on Facebook.

Its use is only limited by your imagination and and the technical tools you have for sending SMS messages.

Both services offer [...]]]> I’ve been using GitHub for a couple of years now for distributing code, but for about the past 6 months I’ve started using Bitbucket, initially in a collaboration for http://max1284.homelabs.org.uk/. Both services offer similar features but at present neither ticks all the right boxes. Below is my comparison of the two.

Both services offer the basic features you’d want:

• Public repositories
• Use standard Git client tools integrated with favourite dev tools
• Issue tracking
• Wiki
• Revision history
• Forking

Comparison

GitHub	Bitbucket
GitHub screenshot	Bitbucket screenshot
$7/m for private repositories, couldn’t determine how many though.	Unlimited free private repositories
No teams, but any number of collaborators on a repository	Free plan can include team of 5 members
Community backed, but uses a .com domain!	Corporate backed but uses a .org domain!
GitHub pages for documentation as well as wiki	Wiki only
Mobile App	Not Yet? Although mobile Git clients could be used
Doesn’t appear to be an import option	Can import repositories from GitHub, but just latest version, no history retrieved.
New features added on regular basis	New features arrive less frequently
Supports Git	Supports Git and Mercurial
	Can use own domain e.g. code.thiseldo.co.uk

Conclusions

At present I’m tending towards Bitbucket mainly because of the free private repositories that will enable code to be kept private if it is work for a customer or before it is released to a wider audience. As a result I’ve started to move a number of my repositories from GitHub to Bitbucket. I’m also re-pointing the Git origin for my local repositories so that they can push to Bitbucket instead of GitHub.

The opinions and views expressed here are my own.

I originally saw a demo of the Vodafone K3770 Mobile broadband dongle given by Ashley Mills of Vodafone at IoT London Meetup 9. In the demo the mbed was receiving SMS and outputting them to a printer. Shortly after this I got myself a Vodafone K3770 dongle and started to see what I [...]]]> Introduction

I originally saw a demo of the Vodafone K3770 Mobile broadband dongle given by Ashley Mills of Vodafone at IoT London Meetup 9. In the demo the mbed was receiving SMS and outputting them to a printer. Shortly after this I got myself a Vodafone K3770 dongle and started to see what I could do with it. At the time the library was still in a beta state so any feedback was welcomed by the team developing it. Eventually the library was released as an official mbed library.

The idea

I had previously done projects with a number of 8×32 LED matrix displays with Arduino and had a code base to work with that could then be ported to the mbed platform. The idea of receiving SMS and displaying them on a scrolling message display sounded like an interesting project to use the mobile broadband dongle with. I had also started using the service IFTTT so the idea of being able to automate messages from weather reports to FourSquare checkins while still being able to receive and display other messages was being formed.

The prototype

The prototype was built on stripboard and consisted of the mbed module, a USB socket, voltage regulator and of course 4 8×32 LED matrix displays giving a total message area of 8×128 pixels. I opted for the horizontal format as this lends itself better to long scrolling messages. Alternative configurations include 16×64 which could give a moving display and a static display to include date/time display.

Mounting the displays

I had a number of reclaimed oak floorboards that I had bought for a woodworking project and thought that mounting the displays in an oak panel would give a combination of old and new things. The oak would also match the furniture in the house so make the display more acceptable as a piece of furniture. The plank was planed and a cutout made using a router. The rear was also recessed to receive the displays.

Software

The software has a number of features:

• Query Network for its phone number
• Display initial message showing its number
• A number of SMS command words are recognised to perform simple actions (e.g. Retrieve balance)

The code is available from my mbeed page ready to import into your own mbed.

Designing a PCB

In order to learn how to use EagleCAD for schematic and PCB design I decided to use this project as a learning exercise with the intention of having a number of boards made.

PCB manufacture

The production files were sent to Seeedstudio using their 2 layer Fusion PCB service. This is a relatively cheap way to have a minimum of 10 boards manufactured. The downside is that it takes a number of weeks for the boards to arrive in the UK form China.

Building first PCB

After just over 2 weeks, the PCBs arrived in all their green glory.

Topside	Underside
First the resistors, diode and other components close to the board.	Add the headers and sockets. At this point the board was powered up and the voltage regulator tested to ensure that all the points that need 5V have the correct voltage.
Completed board

In use

The new board was connected up to the displays and the first problem was noticed, the displays were in the wrong order. Checking the PCB I had drawn the schematic with the different select lines going to different digital outputs on the mbed. This is an easy fix in the code and within minutes it was displaying scrolling messages properly.
The printer port hasn’t yet been tested

Improvements

A couple of people had noted that the copper layer covered the area where the dongle was connected, this could affect the signal being received. The other issue is that if the USB socket is soldered in correctly then the dongle is too fat to be able to fit. This was temporarily solved by raising the connector at an angle but this would put strain on the soldered joints.
Both of these issues can be fixed by altering the shape of the board so there is a cutout where the dongle is.

Todo

• Mount the board on back of display
• Test printer port
• Update PCB with cutout for dongle
• Add licensing details
• Release schematics, parts list and all build files

And finally…

I have a few spare PCBs so if anyone in the UK would like one drop me a message either via my mbed page or via Twitter @andrewdlindsay.

As the two librariers are based on [...]]]> Important Note: I have now stopped development work on the EtherShield library
However, this is not the end for Arduino and ENC28J60 libraries. The excellent EtherCard library from Jeelabs. I have decided this is the library I am to use in my examples and future ENC28J60 developments.

As the two librariers are based on the same original code they share a lot of similarities. One being that I wrote the DHCP code that is used in both the EtherShield and EtherCard libraries. There are a number of things that need to be changed in your sketches in order to use the EtherCard library. These are documented below:

Header file

Replace

#include <EtherShield.h>


with

#include <EtherCard .h>


Library use

Replace

#define BUFFER_SIZE 650
static uint8_t buf[BUFFER_SIZE+1];
EtherShield es=EtherShield();


With

#define BUFFER_SIZE 650
byte Ethernet::buffer[BUFFER_SIZE];


ENC28J60 initialisation

Replace

// Initialise SPI interface
es.ES_enc28j60SpiInit();
// initialize enc28j60
es.ES_enc28j60Init(mymac,8); // To specify CS pin
// es.ES_enc28j60Init(mymac); // To use default CS

es.ES_client_set_wwwip(websrvip); // target web server


With

if (ether.begin(sizeof Ethernet::buffer, mymac) == 0) {
Serial.println( "Failed to access Ethernet controller");
while(1);
}


or, if using a Nuelectronics ENC28J60 shield to use correct select pin

if (ether.begin(sizeof Ethernet::buffer, mymac,10) == 0) {
Serial.println( "Failed to access Ethernet controller");
while(1);
}


Allocate IP Address using DHCP

Replace

es.allocateIPAddress(buf, BUFFER_SIZE, mymac, 80, myip, mynetmask, gwip, dnsip, dhcpsvrip );


With

if (!ether.dhcpSetup()) {
Serial.println( "DHCP failed");
while(1);
}


Allocate IP Addresses using static addressing

Define Addresses with

static uint8_t myip[4] = { 192,168,1,101 };
static uint8_t gwip[4] = { 192,168,1,1 };


Setup library with

ether.staticSetup(myip, gwip);


Resolve DNS Hostname

Replace

if(!es.resolveHostname(buf, BUFFER_SIZE,(uint8_t*)HOSTNAME ) > 0 ) {
Serial.println("Hostname not resolved");
}


With

if (!ether.dnsLookup(PSTR( HOSTNAME ) )) {
Serial.println("DNS failed");
while(1);
}


Other Bits

You might want this bet next just to make sure ARP has been done for Router address:


while (ether.clientWaitingGw())
ether.packetLoop(ether.packetReceive());


Main Processing

Replace

dat_p=es.ES_packetloop_icmp_tcp(buf,es.ES_enc28j60PacketReceive(BUFFER_SIZE, buf));


With

dat_p = ether.packetLoop(ether.packetReceive());


Sending HTTP GET Request

Replace

es.ES_client_browse_url(PSTR("/xyz.php"), "?search=Arduino", PSTR(HOSTNAME), &browserresult_callback);


With

ether.browseUrl(PSTR("/xyz.php"), "?search=Arduino", PSTR(HOSTNAME), &browserresult_callback);


General Packet Buffer Access

Replace

buf[55]


With

Ethernet::buffer[55]


DHCP Lease Expiry

Replace:



With

if (ether.dhcpExpired())
ether.dhcpSetup();


Setting alternative port for http server

Use:

ether.hisport = 1234;


There are more changes but these should cover most cases for now.

Still to address

The EtherCard library still needs a few updates such as:

• Sleep mode
• dodgy TCP implementation allowing only one packet before closing connection