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Arduino Code on Github

I've started uploading my Arduino examples code to Github
https://github.com/alastairhm/arduino

Doodle's Geek Monkey by Alastair Montgomery
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Dusting off the iron

My first attempt at soldering after around eight years away from the soldering iron.



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Counting up to 1023

Decided in the end to wire up all 10 LEDS in the LED bar graph.
Using the sketch below get the results shown in the video.



int numLed = 10;
int ledpins[] = {
  13,12,11,10,9,8,7,6,5,4};
int mask[] = {
  1,2,4,8,16,32,64,128,256,512};
int counter = 0;

void setup() {             

  // initialize the digital pin as an output.
  for (int i=0;i<numLed;i++){
    pinMode(ledpins[i], OUTPUT);
    digitalWrite(ledpins[i], HIGH);
    delay(250);
  }
}
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Arduino Binary second counter

Next step with my Arduino is to set up a binary second counter.
Basic using the LED Bar Graph or six single LEDs to count seconds in binary




/*
Binary Second Counter
 
 Created Alastair Montgomery 22/11/2012
 
 */

int ledPins[] = {
  7,8,9,10,11,12};
int mask[] = {
  1,2,4,8,16,32};
int ledCount = 6;


void setup() {
  for (int thisPin =0; thisPin < ledCount; thisPin++) {
    pinMode(ledPins[thisPin], OUTPUT);
  }
}
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Sanity Checking my new Arduino Uno Board

Quick sanity check of my new Arduino board using a LED Bar Graph.



Here is the sketch I will be using.

int led1 = 8;
int led2 = 9;
int counter = 0;

void setup() {             

  // initialize the digital pin as an output.
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);

}


void loop() {


  if (counter & 1) {
    digitalWrite(led1, HIGH);
  }
  else {
    digitalWrite(led1, LOW);
  }
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Bashing about the command line

Sometimes the best solution is the quickest one, sure I could have written a Ruby script to format the results of the find but a few bash commands achieved the same result.


find /svn/repos -name "authz" -exec grep dev {} ";" | grep -v @dev | cut -d"=" -f 2|sed 's/,/\n/g'|sed 's/ //g'|sort|uniq > /tmp/dev.txt


Doodle's Geek Monkey by Alastair Montgomery
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Using Ruby to send commands over SSH


Doing a lot of work on remote Linux servers lately, lots of login in over SSH running commands logging out.

So wrote this simple script to use Ruby to send a single command or a file of commands to a Linux server over SSH. Needs some error trapping etc but functional at the moment.

It requires the Ruby Gem net-ssh installed.

#!/usr/bin/ruby
require 'rubygems'
require 'net/ssh'
require 'optparse'

 opts = OptionParser.new
opts.on("-h HOSTNAME", "--hostname NAME", String, "Hostname of Server") { |v| @hostname = v }
opts.on("-u SSH USERNAME", "--username SSH USERNAME", String, "SSH Username of Server") { |v| @username = v }
opts.on("-p SSH PASSWORD", "--password SSH PASSWORD", String, "SSH Password of Server") { |v| @password = v }
opts.on("-c SHELL_COMMAND", "--command SHELL_COMMAND", String, "Shell Command to Execute") { |v| @cmd = v }
opts.on("-f FILE_COMMAND", "--command FILE_COMMAND", String, "File containing shell Commands to Execute") { |v| @fileCmd = v }
begin
  opts.parse!(ARGV)
rescue OptionParser::ParseError => e
  puts e
end
raise OptionParser::MissingArgument, "Hostname [-h]" if @hostname.nil?
raise OptionParser::MissingArgument, "SSH Username [-u]" if @username.nil?
raise OptionParser::MissingArgument, "SSH Password [-p]" if @password.nil?
raise OptionParser::MissingArgument, "Command to Execute [-c/-f]" if @cmd.nil? and @fileCmd.nil?

 begin
    ssh = Net::SSH.start(@hostname, @username, :password => @password)
    if @cmd != nil then
        ssh.exec!(@cmd) do |ch, stream, data|
          if stream == :stderr
              puts "ERROR: #{data}"
          else
              puts data
          end
        end
    else
    puts "Processing file #{@fileCmd}"
    file = File.new(@fileCmd, "r")  
    file.each {|line| 
        ssh.exec!(line) do |ch, stream, data|
          if stream == :stderr
              puts "ERROR: #{data}"
          else
              puts data
          end
        end
        }
    file.close
    end
    ssh.close
rescue Exception => e
    puts "Unable to connect to #{@hostname} using #{@username}/#{@password}"
    puts e
end


Doodle's Geek Monkey by Alastair Montgomery
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3d Printing the future

Note: 1 of this post’s 7 links are now broken — mostly dead 2008–2013 feed-syndication infrastructure (FeedBurner, Gawker, AOL’s old blog network, Pheedo, Yahoo Pipes). Left as originally published.

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First boot

http://instagr.am/p/MOCHVnN-hg/

First boot of my Raspberry Pi.
Feel like I'm ten again sat in front of the TV with my Acorn Electron



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Raspberry Pi SD Card problems

Raspberry Cry

Was going to fire up my Raspberry Pi for the first time yesterday but had issues creating boot SD card for it on Windows 7. As you can see here from my post at the Pi Forum.

Looks like it was either problems with my desktop or the SD Card reader I was using as it was getting write errors when using the two Windows methods of creating the boot image.

Hopefully I can get the SD card reformat with GParted so I can try again, most annoying that I tripped up at the first hurdle.

Doodle's Geek Monkey by Alastair Montgomery
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