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Author Archives: Paul Sutton

Torbay Raspberry Pi jam

Posted on 2014-09-13 by Paul Sutton

 

Torbay Raspberry Pi jam – Paignton Library 13:00 to 15:00

 

rsz_b--500x337

 

raspberry_pi_logo

 

Posted in Arduino, coding, education, Events, hacking, Hardware, Internet Safety, Linux, programming, Raspberry pi, Software | Leave a comment |

Net Neutrality

Posted on 2014-09-10 by Paul Sutton
The Honorable Tom Wheeler
Chairman
Federal Communications Commission
445 12th Street, NW
Washington, DC 20554
 
http://www.newbalanceoutlet.cc
Dear Chairman Wheeler:We are writing to urge you to implement strong and unambiguous net neutrality rules that protect the Internet from discrimination and other practices that will impede its ability to serve our democracy, empower consumers, and fuel economic growth. Erecting toll booths or designating fast lanes on the information superhighway would stifle free speech, limit consumer choice, and thwart innovation.

The FCC must act in a clear and decisive way to ensure the Internet does not become the bastion of powerful incumbents and carriers, but rather remains a place where all speakers, creators, and innovators can harness its power now and in the future.

The Internet is a staple of our lives and our economy. The FCC should protect access to the Internet under a Title II framework, with appropriate forbearance, thereby ensuring greater regulatory and market certainty for users and broadband providers.

To ensure that the Internet fulfills its promise of being a powerful, open platform for social, political, and economic life, the FCC must adopt a rule against blocking, a bright-line rule against application-specific discrimination, and a rule banning access fees. These principles of fairness and openness should not only apply to the so-called last-mile network, but also at points of interconnection to the broadband access provider’s network. Likewise, strong net neutrality rules must apply regardless of whether users access the Internet on fixed or mobile connections.

The FCC’s proposed rules would be a significant departure from how the Internet currently works, limiting the economic and expressive opportunity it provides. Investors, entrepreneurs, and employees have invested in businesses based on the certainty of a level playing field and equal-opportunity marketplace. The proposal would threaten those investments and undermine the necessary certainty that businesses and investors need going forward. The current proposed rules, albeit well-meaning, would be far-reaching. Erecting new barriers to entry would result in fewer innovative startups, fewer micro-entrepreneurs, and fewer diverse voices in the public square. The FCC should abandon its current proposal and adopt a simple rule that reflects the essential values of our free markets, our participatory democracy, and our communications laws.

When the history of the Internet is written, 2014 will be remembered as a defining moment. This FCC will be remembered either for handing the Internet over to the highest bidders or for ensuring that the conditions of Internet openness remain for the next generation of American entrepreneurs and citizens. We urge you to take bold and unequivocal action that will protect the open Internet and the opportunity it affords for innovation, economic development, communication, and democracy itself.

 

https://www.battleforthenet.com

Posted in Uncategorized | Leave a comment |

Enabling students in a digital age:

Posted on 2014-09-08 by Paul Sutton

Enabling students in a digital age: Charlie Reisinger at TEDxLancaster

This is interesting lets do this in Torbay.

Posted in education, Linux, respect, trust | Leave a comment |

hack4good pre-event webcasts

Posted on 2014-09-05 by Paul Sutton

You can build/design apps? Why not put your powers to good? Join us at #hack4good as we hack #ClimateChange together https://geekli.st/hackathon/hack4good-06

Global Pre-Event Webcasts Schedule is out!

We have exclusive webcasts all next week with Save the Children, WWF, Fauna & Flora International, Lead International, WeForest, WRI, King Tides Network and Forum for the Future!

https://twitter.com/dancunningham/status/507984989267296257

Please share and spread widely in all of your networks!

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Torbay Pi Jam – Call for papers

Posted on 2014-09-01 by Paul Sutton

As I am part of the team that run the Torbay Pi Raspberry Pi jam.  This is a call out for anyone who would like to either do a demonstration or do a talk at a future pi jam,.

So, If you would like to do a talk or demo or can help in other ways please get in touch,

Posted in Arduino, coding, Courses, Events, FabLab, hacking, Hardware, Internet Safety, Linux, programming, Raspberry pi, Software | Leave a comment |

Mesh Networking in Scratch – The way to interface practically anything to scratch.

Posted on 2014-08-30 by Paul Sutton

Introduction

The Scratch development platform is a great way for younger coders to get into computer programming with it’s simple “lego brick” style of drag and drop code construction. However interfacing hardware to it can be a little bit tricky (although not totally impossible).

One feature of Scratch that can be very useful is the mesh network feature which provides a mechanism for broadcasting messages and sharing variables (as “sensor-updates”) via standard network sockets.

This feature means that practically any modern computer language (python,c,c++,java,php to name but a few) could be used to interface to a scratch session via the mesh. For example these languages can be used to directly interface other hardware such as game controllers (wii remotes, console game pads etc.), to scratch via the mesh network.

There are two little wrinkles in this plan however. Firstly because the program is acting as a proxy between the hardware and scratch via a network connection the response can be sluggish. Press button here and wait half a second plus before scratch responds. This isn’t the nanosecond responses that console games expect in “real world” game titles, but this is scratch games, not the next multinational block buster game.

The second wrinkle is that you have to turn on the Mesh networking. Not the hardest thing to do in the world, but one should be aware of what mesh networking is doing in the background. For one thing its allowing anything that understands the Mesh networking protocol (which I will be explaining later in this article)  to access variables in your scratch session without a single nod or wink to authentication or security (because frankly mesh networking on scratch has none). If you think of a scratch variable holding one of your private emails then switching on mesh networking would allow another computer on the same local network to access that email. Worse still if you open up port 42001 on your firewall then potentially anyone on the Internet could access your scratch session. The good news here is that by default it is highly unlikely that your firewall will have opened up port 42001 to any machine on your local network (let alone one used by a primary school child).  However it is possible to do this through your firewall management software and there maybe a point where you would want to consider a school-to-school project link. If that opportunity does ever arise, open up your firewall to port 42001, do the exercise, close down access to port 42001, job done.

Having said all that, the reality is that you will not (should not) be doing anything that sensitive with scratch. By making you aware of the minor risks and dangers in opening up mesh networking (when compared to the benefits that it brings to young coders discovering new ways to do things like inter process communication), I am hoping that you will be able to appreciate the issues involved and head them off in the more controlled environment of the classroom. The most likely scenario is when some bright kid realised that they can snoop on another kids classroom project by connecting to his/her mesh. If that happens credit them for having a deeper understanding of how mesh network works with Scratch… but also take some time to explain to them the ethical issues of doing such things “unannounced” with a hope that they will grow up to be network security consultants not master cyber criminals…..

Most importantly be aware of how it works  yourself. If you know how to detect it (and hopefully this article will explain it well enough for you to understand) then it probably will never happen. And even an “up front” lesson on ethical computing would not go amiss. Give them the old spiderman pep talk “with great power comes great responsibility ….”

Turning Mesh On

I could write a really boring sub section on this but frankly M.I.T’s own instructions for doing this pretty much cover it, after all they did develop Scratch so they should have an idea or two about how it works! See: http://wiki.scratch.mit.edu/wiki/Mesh

The only other thing I would add to this from my own personal experience is that while turning mesh networking on for Scratch on Linux based systems like the Raspberry Pi you will need to run it as root (sudo scratch) from the console. If you don’t do this it will probably freeze up as the “save” stage and you will have to follow the instructions all over again.

Once you have updated the image with mesh enabled you will be able to switch it on/off from within any scratch session started as a “normal” user via the usual desktop shortcut link.

My Python ScratchListener Class

I have adopted and adapted other peoples work in constructing my own “ScratchListener” class. The code is meant as a test piece framework for someone to add new features to or interface new devices to scratch

Source code   
from array import array
import threading
import struct
import socket
import time
import sys
 
class Scratch():
 
def __init__(self):
PORT = 42001
HOST = 'localhost'
 
if not HOST:
sys.exit()
 
print("connecting...")
self.scratchSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.scratchSock.connect((HOST, PORT))
print("connected")
 
def send(self,cmd):
print(cmd)
head = len(cmd).to_bytes(4,byteorder="big")
self.scratchSock.send(head + cmd.encode("utf-8"))
 
def broadcast(self,message):
self.send("broadcast %s" % message)
 
def update(self,variable,value):
self.send("sensor-update \"%s\" %s" % (variable,value))
 
def recv(self):
return(self.scratchSock.recv(1024).decode("utf-8",'replace'))
 
class ScratchListener(threading.Thread):
 
def __init__(self):
 
threading.Thread.__init__(self)
 
PORT = 42001
HOST = 'localhost'
 
if not HOST:
sys.exit()
 
print("connecting...")
self.scratchSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.scratchSock.connect((HOST, PORT))
print("connected")
 
def run(self):
 
while(True):
 
data = self.scratchSock.recv(1024)
length = struct.unpack(">l",data[0:4])[0]
pdata = data[4:].decode("utf-8")
 
if(length != len(pdata)):
print("Data Length Missmatch on received data")
return
 
print("Data Received %d %s" % (length,pdata))
self.process(pdata)
 
def process(self,pdata):
 
if("sensor-update" in pdata):
print("Sensor Stuff")
parts = pdata.split(" ")
variable = (parts[1])[1:-1]
val = (parts[2])
exec("%s_temp = %s" % (variable,val))
print(external1_temp)
 
def send(self,cmd):
print(cmd)
head = len(cmd).to_bytes(4,byteorder="big")
self.scratchSock.send(head + cmd.encode("utf-8"))
 
def broadcast(self,message):
self.send("broadcast %s" % message)
 
def update(self,variable,value):
self.send("sensor-update \"%s\" %s" % (variable,value))
 
def recv(self):
return(self.scratchSock.recv(1024).decode("utf-8",'replace'))
 
# Main....
 
if(__name__ == "__main__"):
scratch = ScratchListener()
scratch.start()
external1 = 0
 
while(True):
#scratch.send("broadcast broadcast")
#scratch.send("sensor-update \"external1\" %d " % external1)
#scratch.send("sensor-update \"external2\" %d " % external1)
#scratch.send("set variable \"external1\" to %d" % external1)
#scratch.send("broadcast hello")
#scratch.broadcast("broadcast")
 
#print(scratch.recv()[4:])
 
scratch.update("external1","%d" % external1)
#scratch.broadcast("broadcast")
 
time.sleep(5)
 
external1 = external1 + 1

http://www.nikeairmaxfreedom.com nike air max 2015

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Gimp – Picture resize

Posted on 2014-08-27 by Paul Sutton

I have pulled in the tutorial from my website to the DCGLUG website,  this can be found at

http://www.dcglug.org.uk/gimp-picture-resize-tutorial/
http://www.nikeairmaxfreerun.com nike air max 90

Posted in Uncategorized | Leave a comment |

Job Vacancy : Digital Experience Manager

Posted on 2014-08-26 by Paul Sutton

LOCAL JOB VACANCY

Employer: SOUTH WEST GRID FOR LEARNING TRUST
Link to details : http://www.devonjobs.gov.uk/management-south-west-grid-for-learning-trust-digital-experience-manager/44066.job

 

  • Closing date:19 September 2014
  • Based at:Exeter

 
http://www.nikeairmaxfreedom.com nike air max

Posted in jobs | Leave a comment |

Sound converter tutorial

Posted on 2014-08-26 by Paul Sutton

I have added a simple sound converter tutorial to the website resources section

http://www.dcglug.org.uk/sound-converter/
http://www.nikeairmaxfreedom.com air max 95

Posted in Uncategorized | Leave a comment |

Global Hackathon

Posted on 2014-08-17 by Paul Sutton

 hack4goodlogo

Global hackathon 12-14 Sep 2014

0.6: hack against catastrophic climate change.

http://hack4good.io/  #hack4good

Flyer global H4G06 - LONDON2
http://www.nikeairmaxfreedom.com nike air max sneakers

Posted in Uncategorized | Leave a comment |
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