Guava Jelly

 Food, my projects  3 Responses »
Apr 082012
 

When life gives you lemons you make lemonade. Lemons are out of season but my guava tree is laden with fruit and it is easier to pick it off the tree than to deal with the purple mess when the fruit drops to the ground. Hence, guava jelly:
A small jar of guava jellyIngredients:
Guavas, lots in various stages of ripeness.
Sugar, more than you think. No, even more than that.
Pectin, don’t worry I won’t tell
A Lemon
You will also need a jelly bag or similar device.

Method
Wash the guavas and remove any stems and leaves. Put the fruit in a large pot with a little water, cover and boil gently until the fruit is all soft and split – about 20 minutes or so. Add more water if required. Make sure all the fruit has opened, you can help things along by mushing it gently with a potato masher, but don’t get too vigourous.

Let the mixture cool then pour it carefully into the jelly bag sitting in a large bowl. It is possible to use a pillow case, or even a folded tea towel for this if you don’t have a jelly bag – they do the same job. The guavas will turn anything they touch purple but the colour washes out. I wouldn’t use my best pillow cases though.

Tie up the jelly bag and hang it over the bowl in an out-of-the-way place for 12 hours. Gravity will force the juice out, leaving the pulp behind. You will feel a strong urge to squeeze the bag – resist temptation! If you force the pulp trough the bag the jelly will become gritty.

Transfer the juice to a pot and bring to the boil. Let the juice boil down a little depending on how strong you want the jelly to taste. Jellies need both sugar and pectin to set properly. Technically the fruit contains enough pectin to set the jelly if you add enough sugar but this has never worked for me. Using store bought pectin ensures a good result and allows you to use less sugar. Even with the extra pectin you still need a lot of sugar – about 3 cups of sugar for every 4 cups of juice should do the trick, depending on the sweetness of the fruit. Pectin also needs an acid to work, so add the juice from the lemon.

Boil the mixture vigourously for a few minutes then boil gently to let the juice reduce for 20-30 minutes. After a while you should see the mixture start to congeal around the edges, this is a sign that the jelly is nearly ready. Use a spoon to skim off the worst of any froth that appears on top of the mixture. Let it boil some more, then pour into pre-heated jars. Hopefully the jelly will set in the follow hours. If not, boil it up some more.

Serve with dark meat or strong cheese.

Onion, Pear and Feta Pizza

 Food, my projects  No Responses »
Mar 112012
 

People seemed to like the first pizza post, so here is another one. Something a little different this time – very simple but delicious.
A Pear and Feta Pizza

Ingredients:

Base
1 Cup Flour
Splash of Olive Oil
Cold Water
Teaspoon of Salt
Teaspoon of Baking Powder
Topping
2 Medium Pears
1 Clove of Garlic
1 Red Onion
Tiny bit of white sugar
Enough Feta
More olive oil and a knob of butter
Water

Method:
Make a dough from the flour, oil, water, salt, and baking powder and kneed well. More detailed instructions are in my last pizza post. Heat the oven (and the oven tray) to 200°

Melt the butter with the olive oil in a frying pan. Slice the onion finely and gently sauté for 5-10 minutes until the onion start to shine. Add in just a little (half a teaspoon or so) of sugar and continue to cook. Add the finely chopped garlic and cook some more, don’t let it burn. Remove the onion mixture from the pan.

Peel, core, and slice the pears into wedges, removing the pips. Add a little water to the pan that the onions were cooked it and add the pears. Let the water boil down for a while to soften the pears then add some more butter and a little sugar. Sauté for a few minutes until the wedges are soft and just starting to brown.

Take the pizza base and put it on the heated oven tray. Top with the onions, then the pears, finally crumbling feta across the top. Place in oven and wait.

Homemade Pizza Recipe

 Food, my projects  No Responses »
Feb 192012
 

Homemade pizza sitting on a chopping block

I often make pizza from scratch, it is a great way of using up various bits and pieces I have lying around. Over the years I have tried various recipes for the base, but this is my favorite (and also the easiest). I am particularly proud of this effort because a lot of the ingredients came from my garden.

Ingredients:

Base
1 Cup Flour
Goodly splash of olive oil
Cold Water
teaspoon of salt
1/2 teaspoon Baking Powder
Toppings
Whatever you can find in the fridge/garden, in this case:
Tomato paste
3 baby leeks chopped
2 cloves of Garlic, finely chopped
2 small Tomatoes, very thinly sliced
Red Pepper, sliced
Mozzarella Cheese, sliced
Basil Leaves
Salt/Pepper
Olive Oil

Method:
Put flour, salt, and baking powder in a bowl and pour in the oil (about 2-3 table spoons, maybe more). Pour in a little water and mix. If the flour is still dry, tip just a little more water in but go slowly – it is easy to make it too wet. You want a soft dough, not a cake mix. If you go too far put in some more flour.

Take the dough out and kneed it for a few minutes to complete the mixing, then wrap the dough ball in plastic wrap and let it sit for 30 minutes on the bench.

Put your heaviest (the heavier the better) cooking tray in the oven and heat to 220°C.

Take out the dough and kneed again then divide into 2 or 3 hunks. Roll out each hunk into a roughly circular shape a few millimeters thick. Put the bases on the hot cooking tray and add toppings.

Smear the top of the base with tomato paste, like you were spreading jam on toast. Next put the chopped garlic and leeks (normally I would use onion, but I just happened to have leeks). Slice the tomatoes as thinly as you can and add them along with the basil leaves. Finally slice the mozzarella and put that on top as well – it doesn’t have to cover everything.

Don’t try to heap too much on the pizza – it needs to cook quickly to get crispy.

Salt and pepper to taste and drizzle on a decent amount of olive oil. Put back in the hot oven and cook until it looks like a pizza. Serve with wine, salad, another pizza.

Tiger Slug – Limax Maximus

 my projects  1 Response »
Feb 022012
 

Side view of the Tiger Slug

I disturbed this fellow while gardening today. He took off at speed across my lawn but since he is a slug I had plenty of time to get my camera a snap a few shots.

This is Limax Maximus – the Tiger Slug (or Leopard Slug depending on whether you like the striped tail or the spotted mantle) and they are impressively large. My garden is full of them. Most slugs I kill on sight, but I leave the Tiger Slugs alone because they supposedly kill other garden pests. Besides, they give me a slow moving target to practice macro photography.

Front view of the Tiger Slug

Arrrggh, it’s coming right for me!

Jumping Frogs – Using Python to Solve Puzzles

 Computer, Games, my projects  No Responses »
Nov 272011
 

A few months ago I came across the following puzzle in a video game I was playing:

The starting position for the siz frogs puzzleThree frogs are happily hopping along a narrow board together when they meet another group of three frogs traveling in the opposite direction. These frogs can only move in the direction they are facing, and only if there is a space directly in front of them. Additionally, a frog can jump over the frog in front but only if there is clear space on the other side to land in.

How can the frogs (moving one at a time) pass each other and continue on their way?

Of course, this is a hoary old puzzle that most people come across and solve as children. It should be only a couple of minutes work with a pen and paper to confirm that it is possible to exchange both sets of frogs but I wouldn’t be much of a programmer if I used a piece of paper where hundreds of dollars of computer equipment would do just as well.

To solve a puzzle like this programatically requires three things: a representation of the current state of the problem, a way of generating every possibly legal move from a given position, and a way of figuring out when is a good time to stop.

Firstly, the representation of the board is a simple python list:

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start = [1, 1, 1, 0, -1, -1, -1]

Frogs traveling right or left are represented by “1″ and “-1″ respectively. Empty spaces that frog can move into are represented by “0″. The advantage of this representation is that you can calculate the new position of a frog by:

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newPos = pos + (representation * distance)

where pos is the current index in the array, distance is the size of the hop (either 1 or 2) and representation is either 1 or -1.

Next, we need a way of generating legal moves for a given position:

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def legalMoves(board):
	moves = []
	for pos, piece in enumerate( board ):
		jumpmove = pos + (piece * 2)
		move = pos + (piece)
		if ( piece == 0 ):
			continue
		if (not (( jumpmove < 0 ) or ( jumpmove >= len(board)))):
			if (board[jumpmove] == 0):
				t = list(board)
				t[pos] = 0
				t[jumpmove] = piece
				moves.append(t)
		if (not ((move < 0) or ( move >= len(board)))):
			if ( board[move] == 0):
				t = list(board)
				t[pos] = 0
				t[move] = piece
				moves.append(t)
	return moves

Now we need a way of keeping track of all board positions we have seen, so once we find the target we can print the states that led to the solution:

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def evalAll( current, target ):
	next = []
	for a in current:
		n = legalMoves(a[-1])
		for q in n:
			t = list(a)
			t.append(q)
			if ( q == target ):
				return t
			next.append(t)
	return next

This code keeps a list of lists, each sublist being it’s own list of the sequence of moves investigated so far. For each sequence of moves, the next legal moves are discovered and new sequences are added to be investigated the next time this function is called. Technically this is called a breadth-first search because at all of the current legal moves are investigated before moving on the next stage. This is a very simplistic way of doing the job, but in this case the puzzle is small enough that it works well enough.

Finally, a simple wrapper that we can use to set things up and return the final result.

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def solve(start):
	temp=[[start]]
	end = list(start)
	end.reverse()
	while(temp[-1] != end):
		temp = evalAll(temp, end)
	return temp

So now we can do this:

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print solve([1, 1, 1, 0, -1, -1, -1])
 
[[1, 1, 1, 0, -1, -1, -1],
 [1, 1, 0, 1, -1, -1, -1],
 [1, 1, -1, 1, 0, -1, -1],
 [1, 1, -1, 1, -1, 0, -1],
 [1, 1, -1, 0, -1, 1, -1],
 [1, 0, -1, 1, -1, 1, -1],
 [0, 1, -1, 1, -1, 1, -1],
 [-1, 1, 0, 1, -1, 1, -1],
 [-1, 1, -1, 1, 0, 1, -1],
 [-1, 1, -1, 1, -1, 1, 0],
 [-1, 1, -1, 1, -1, 0, 1],
 [-1, 1, -1, 0, -1, 1, 1],
 [-1, 0, -1, 1, -1, 1, 1],
 [-1, -1, 0, 1, -1, 1, 1],
 [-1, -1, -1, 1, 0, 1, 1],
 [-1, -1, -1, 0, 1, 1, 1]]

Success!

You might say this is a waste of time since you figured out the problem in your head. Good for you, but try this on for size:

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[1, 1, 1, 1, 1, 1, 1, 1, 0, -1, -1, -1, -1, -1, -1, -1, -1]

Stuff from my Old Hard Drive

 Computer, Culture, my projects  No Responses »
Nov 102011
 

I don’t usually keep a lot of files around. When I get a new computer I don’t tend to copy all my documents across – anything I haven’t looked at for a couple of months is probably not worth the fraction of a millimetre it takes up on the platter. On the other hand, some things I can never bring myself to delete. Here is something I rediscovered the other day:

This is one of the first MODs I wrote back on the Amiga. I never had a sampler or a very large collection of instruments, but I loved mucking around with MED trying to get a pleasant sound out of the 4 channel 8-bit sound. It is often said that there is a lot of crossover between programming and music, and the soundtracker clones of the 90s made that explicit which is possibly why I enjoyed it so much. Now days I can fire up GarageBand any time I want with any number of sampled instruments. I could say that I regret not having the time to produce music as an adult but the truth is that the inspiration isn’t there any more – my interests have moved in other directions.

Although none of my MODs ever sounded anything like as good as the music from the games and demos of the time, I am still pretty pleased with this one. It must date from form 6 (I was 16) which makes it vintage 1991. Listen to the sound of 20 years ago…

Jungle Drums MP3
Jungle Drums OGG

Google+ Social Media Features

 Computer, my projects  No Responses »
Sep 272011
 

Blog writers want feedback. For ages now I have been running a plugin on this blog that allows readers to quickly post things I have written to Twitter, Reddit, Facebook, etc in the hope that some of my wittier and more insightful musings might be widely distributed. The icons were there for years and, as far as I can tell, the icons were clicked exactly none times. None.

So I have removed that plugin and am trying something else.

Google+ is Google’s attempt at social media (previously) and I am liking a lot of what they are doing. It is sort of like a mixture of Twitter and Facebook, you can follow people without them reciprocating and anything you post can be shared with only a subset of people. +1 is Google’s equivalent of Facebook’s Like button.

If you are logged into G+ you can click on the +1 button to show you approve of the content and want to see more like it. You can go back through the archives and +1 as many articles as you want – go ahead, I’ll wait.

In addition, I have added my Google Plus feed to the sidebar on the right. I am not sure if I will keep this, I post very few updates, but we will see. I quite like having my long form blog posts and my short for G+ updates visible in one place.

Arduino Powered Tachistoscope

 Computer, my projects  No Responses »
Aug 092011
 

About fifteen hundred years ago I wrote WordApp, a Java applet tachistoscope that reads a text file from either the local filesystem or the Internet and displays it one word at a time. The idea is that it trains your brain to recognise words quickly, increasing your reading speed. I thought it was a little silly, but according to me web host’s logs WordUp still sees a bit of use even though I haven’t touched it for years.

I was hunting around for something to do with my Arduino while I waited for some other parts to arrive when I had the idea of making a physical tachistoscope that reads its data off an SD card and displays the text using an LCD display I have lying around.

The SD card contains the text to be shown. One of the potentiometers is used to vary the contrast on the LCD. The other is sampled by the CPU and converted into a delay to vary the speed at which the words appear.

Unfortunately the refresh rate of the LCD is very poor, so the text becomes almost impossible to read at even modest speeds. A better display might help, but I am not going to spend any more time and money on something so simple. Fortunately, the other parts I ordered arrived yesterday so I have other things to play with.

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/*
An Arduino implementation of a Tachistoscope.
This uses both the LiquidCrystal and SD libraries (and repective devices). The 
words are read one at a time from a file on the SD card. A simple variable resistor
is used to control the speed.
In practice this does not work terribly well since the LCD display has a poor
refresh rate.
 
Pins: 
The LCD is connected via pins 2-8. Technically I could get away without the RW pin.
The SD card reader is connected via pins 10-13 (the standard SPI pins)
The variable resistor is connected via analog A0
 
Author: Andrew Stephens http://sandfly.net.nz/
*/
 
#include <LiquidCrystal.h>
#include <SD.h>
 
LiquidCrystal lcd(8, 7, 6, 5, 4, 3, 2);
File file;
 
void setup()
{
  lcd.begin( 16, 2 );
  lcd.clear();
  lcd.setCursor(0, 0);
 
  pinMode(10, OUTPUT);  // required if I ever change the CS pin from 10
  pinMode(A0, INPUT);
 
  SD.begin(10);
  file = SD.open("test.txt");
}
 
// Skip over whitespace, positions the file position at the start of the next
// word
bool findNextWord( File& file )
{
  int r;
  while ((r = file.peek()) != -1 )
  {
    if ( !isSpace(r) )
    {
      return true;
    }
    file.read();
  }
  return false;  
}
 
// Reads a single word (anything up to the next whitespace character) into
// the given buffer
bool getNextWord( File& file, char* buffer, int bufferSize )
{
  int r;
  while ((r = file.read()) != -1 )
  {
    if ( isSpace( r ) )
    {
      *buffer = '\0';
      return true;
    }
    if (bufferSize > 1 )
    {
      *buffer = r;
      ++buffer;
      bufferSize--;
    }
  }
 
  *buffer = '\0';
  return false;
}
 
 
// originally this function did more
int readResistor()
{
  return analogRead(A0);
}
 
 
void loop()
{
  char buffer[17];
 
  if (findNextWord( file ) )
  {
    getNextWord( file, buffer, sizeof(buffer) );
    lcd.clear();
    lcd.print( buffer );
  }
  else
  {
    lcd.clear();
    lcd.print("--end--");
  }
  int v = readResistor();
  lcd.setCursor(0, 1);
  lcd.print( v );
  delay(v);  
}

New Server

 my projects  No Responses »
Jul 292011
 

Regular followers of this website may have noticed that it has been offline for the best part of 24 hours. This was to get it moved from my hosting company’s legacy server to a more modern machine. I use OpenHost for hosting sandfly.net.nz, they perhaps are not the cheapest option (especially if you consider American bulk hosting) but on the plus side they actually rang me yesterday when they saw that I was lost in the maze of account options that their customer portal provides.

The upgrade went smoothly enough although next time I will remember to disable any WordPress plugins before doing the backup since some of them seem to not like being moved. Bouncing them back to active seemed to do the trick.

All this kerfuffle was just to upgrade WordPress to the latest point release. I think everything is working, although I have lost any WordPress comments made yesterday. Let me know if you see any (unintentional) weirdness.

 Posted by at 10:41 am

Arduino POV Device Part II

 Computer, my projects  No Responses »
Jul 182011
 

Last week I wrote about starting with digital electronics with the Arduino prototyping platform. Getting something working was easy enough but I was dissatisfied with ugly result, especially when my friend Lloyd showed up with his extremely tidy version of the same idea. The piece of cardboard had to go!

My first version used a breadboard and uncut LED leads because I thought that I would want to dismantle the components for reuse. However I have since realised that I am a grown man with a career and can easily afford the $4.50 material cost. Behold POV version 2:



I won’t be entering this in any soldering competitions but it works OK.

The code has also changed. Compiling in what amounts to a 2D bitmap was a quick way to get something up and running but it wasn’t very flexible, especially since in the future I want to display long strings of text. This means storing glyphs (letter shapes) for every letter of the alphabet (plus digits and symbols) – what I needed was a proper font; what I got was this:

I then turned to Python to generate the program data to embed in the new Arduino code. This script slices the image vertically, generating one byte (actually only 7 bits) for each slice of pixels. What comes out is a long list of byte values that can be output directly to the Arduino’s IO pins to display each section of the text, along with a set of indexes that map letters to the start and end positions of individual glyphs in the array.

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import sys
 
def GetSlice(i, pos):
	t = 0
	for q in range( pos, len(i), len(i) / 7 ):
		t = t * 2
		if ( i[q] != '\x00' ):
			t = t + 1
	return t
 
def GetGlyph( i, pos ):
	end = pos
	start = pos
	data = []
	while (end < len(i) ):
		t = GetSlice( i, end )
		if ( t == 0 ):
			break;
		data.append( t )
		end = end + 1
	return (start, end, data)
 
def GetFont( d ):
    result = []
    i = 0
    currentIndex = 0
    indices = []
    while ( i < len(d) / 7 ):
	(start, end, data) = GetGlyph( d, i )
	if ( len(data) == 0 ):
		break
	i = end + 1
	indices.append( currentIndex )
	currentIndex = currentIndex + len(data)
	result.extend( data )
    return ( result, indices )
 
if __name__ == '__main__':
    if ( len(sys.argv ) != 3 ):
        print "USAGE: program <input> <output>"
        exit()
    data = []
    i = file( sys.argv[1], "rb" )
    data = i.read()
    i.close()
    ( d, indices ) = GetFont( data )
    o = file( sys.argv[2], "w" )
    o.write( "static const int indices[] = { " + ",".join(map(str, indices ) ) + " }; ")
    o.write("\n")
    o.write( "static const unsigned char fontdata[] = { " + ",".join(map(str, d)) + "};")
    o.write("\n")
    o.close()

This scheme is more complex that the original bitmap but allows arbitrary text to be display without lots of editing. The modified Arduino code now looks like this. The first two lines contain the new font data, and you can see that the text to display is simply declared on line 5.

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static const int indices[] = { 0,4,8,12,16,19,22,26,30,33,37,42,45,52,59,63,67,71,75,79,82,86,91,96,101,106,111,116,121,126,131,136,141,146,151,156,161,163,165,167 }; 
static const unsigned char fontdata[] = { 63,72,72,63,127,73,73,54,62,65,65,34,127,65,65,62,127,73,65,127,72,64,62,65,69,39,127,8,8,127,65,127,65,2,1,1,126,127,8,20,34,65,127,1,1,63,64,64,60,64,64,63,127,32,16,8,4,2,127,127,65,65,127,127,72,72,48,62,65,71,62,127,72,76,51,50,73,73,38,64,127,64,126,1,1,126,112,12,3,12,112,126,1,15,1,126,65,54,8,54,65,96,16,15,16,96,67,69,73,81,97,62,69,73,81,62,17,33,127,1,1,71,73,73,73,49,65,65,73,73,54,24,40,72,127,8,121,73,73,73,6,62,73,73,73,6,65,66,68,72,112,54,73,73,73,54,48,73,73,73,62,3,3,123,123,27,27,127};
 
static int outputPins[] = { 12, 11, 10, 9, 8, 7, 6 };
static char text[] = "ANDREW";
 
void setup()
{
  for (int i = 6; i<=12; ++i)
  {
    pinMode(i, OUTPUT);     
    digitalWrite(i, HIGH);
  }
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);
  delay(2000);
}
 
void loop()
{
  byte row = 0;
  byte endRow = 0;
  char* currentChar = text;
 
  while (1)
  {
    if (*currentChar == 0)
      currentChar = text;
    if ( row == endRow )
    {
        char t = *currentChar;
        currentChar++;
        t = t - 'A';
        row = indices[t];
        endRow = indices[t+1];
    }
    while (row != endRow)
    {
      byte mask = 64;
      for (byte pin = 0; pin < (sizeof( outputPins) / sizeof(outputPins[0])); ++pin )
      {
        digitalWrite( outputPins[pin], (fontdata[row]&mask)? HIGH : LOW  );
        mask = mask / 2; // divide mask by two, moving it down one bit
      }
      row++;
      delay(1);
    }
    for (byte pin = 0; pin < (sizeof( outputPins) / sizeof(outputPins[0])); ++pin )
    {
      digitalWrite( outputPins[pin], LOW);
    }
 
    delay(1);
  }
}

Still to do: This code is not very efficient. It uses digitalWrite() in a loop to turn on the LEDs. digitalWrite() is very easy to use but if you look at the source code you will see it does all sorts of unnecessary stuff for this job. I plan to replace it with direct writes to the required Arduino IO registers.

I also want to make the whole thing interrupt driven to free up the CPU. Why would I want the extra CPU time? I have plans for that as well…

Starting with Arduino

 Computer, my projects  No Responses »
Jul 142011
 

I have a new hobby – digital electronics! Last week I bought an Arduino Uno on a whim from JayCar. Being a typical programmer, I have very little idea how computers actually work on the physical level so this gives me an easy introduction to lower-level coding and electronics in general.

The Arduino is a small board with a fairly capable 8 bit microprocessor (an ATmega328 to be precise) with the IO pins hooked up to convenient headers ready for attaching external devices. The CPU has its own RAM and programmable flash memory, and it comes with a bootloader that can reprogram the flash via the handy USB connection (which can also power the whole board). It is hard to imagine a more plug-n-play device.

I decided that I would follow the well-worn path and create a persistence of vision device for my first project. Mine consists of 7 LEDs hooked up to IO 7 pins (via appropriate resistors), the idea is to make the LEDs blink in such a way that recognisable shapes appear as the LEDs are waved quickly in front of your eyes.

My prototype is a little rough, but works fine in a darkened room (I was too cheap to spring for super bright LEDs and the darkness hides my shoddy soldering job.) The breadboard is too fragile to wave around so the LEDs are mounted on cardboard and connected using a couple of metres of CAT5, which conveniently has 8 internal wires to supply the 7 LEDs with a common ground. The total cost is less than $10, excluding the breadboard and the Arduino itself.

The Arduino programming environment is pretty nifty. The language used is a limited form of C++ (no standard library or runtime support for much of anything) with some extra libraries for managing the CPU’s features. Compiling and flashing the CPU is as simple as pushing a button. Here is the code that generated the above picture:

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// Array holding the graphic to display
static char* text[] = {
" XX   X     X  XX     XXXX   XXXX  X     X     ",
"X  X  XX    X  X  X   X   X  X     X     X     ",
"X  X  X X   X  X   X  X   X  X     X     X     ",
"XXXX  X  X  X  X   X  XXXX   XXX   X  X  X     ",
"X  X  X   X X  X   X  X X    X     X  X  X     ",
"X  X  X    XX  X  X   X  X   X     X  X  X     ",
"X  X  X     X  XXX    X   X  XXXX   XX XX      " };
 
static int outputPins[] = { 12, 11, 10, 9, 8, 7, 6 };
static int graphicLength;
 
 
void setup()
{
	// setup the initial state of the pins
  for (int i = 6; i<=12; ++i)
  {
    pinMode(i, OUTPUT);     
  }
	// pin 13 is hardwired to the onboard LED, turn it off
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);
 
  graphicLength = 0;
  for (char* t = text[0]; *t!=0; ++t)
  {
    ++graphicLength;
  }  
}
 
void loop()
{
  while (1)
  {
    for (int i = 0; i < graphicLength; ++i )
    {
		// find out if the pin is supposed to be on (HIGH) or off (LOW)
      for (int pin = 0; pin < (sizeof( outputPins) / sizeof(outputPins[0])); ++pin )
      {
        if (text[pin][i] == ' ')
        {
          digitalWrite( outputPins[pin], LOW );
        }
        else
        {
          digitalWrite( outputPins[pin], HIGH );
        }
      }
      delay( 1 );
    }
  }
}

Not very efficient but simple enough to get going. I am already working on a more functional version which will have its own font and interrupt driven display.

State Highway Death : Turn Right for Murder

 Culture, my projects  1 Response »
Jun 092011
 

Here is our entry for the 2011 48 Hour Film Competition:



Watch on Youtube

The reviews were not kind, but everyone had fun making it. The elements this year were a character called Bobby Young, the dialog “What have you got”, a piece of bent wire, and the film had to end on a freeze frame. Our genre was “Road Movie”, to be honest I think we ended up with more of a revenge film (one of the other genres) but I think we got in enough travel to make it count.

My contribution was mainly as the camera operation, although I helped write the original script and directed the odd scene. It is my fault that Bobby is out of focus in the last scene – hi-def video is unforgiving.

A Helpful Gardening Tip

 Culture, my projects  No Responses »
Jun 072011
 

Here is something I learnt today. Pruning and trimming trees and shrubs around your property is a tedious job – unless you make it personal.

“This one’s for Sonny Bono and the fighting Uruk-hai, you angiospermic bastards!”

A pile of branches in my back yard

Well, it makes me feel better.

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