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Petri Häkkinen
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Shinobi Shader System
Shaders for my Shinobi engine are written in Lua programming language. Why Lua? Lua with its dynamic typing and first class functions makes it easy to generate shader permutations -- a hard problem to solve in a C like language with limited preprocessor pow...

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Hacked kid toy
Wow, a year has passed with no updates! Let's fix that right now. Sometime last fall my son got a kid's toy which would play this really annoying 10 second bleep bloop loop (anybody with kids know what I'm talking about). After torturing the family with it ...

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ERIC-1: Video Memory Interface
The ATmega1284P coprocessor of ERIC-1 has been able to output a PAL video signal for some time. As you may know, the coprocessor has a screen buffer of 50x32 characters and a 2KB character rom table storing the glyphs of the character set. All this data is ...

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ERIC-1: CPU Upgrade
I recently got a delivery of two brand new W65C02S chips from Coltek UK (£9 for two chips including shipping to Finland, not bad!). Now, if this didn't ring a bell, here's some news for you: 6502 microprocessors are still made even today. According to Weste...

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ERIC-1: Bitbanging the video signal
I've been working on video signal generation for my ERIC-1 microcomputer lately. As you may know I built a 8-bit console in the past that generated a composite video signal using an ATmega328P microcontroller. The microcontroller outputted an 8-bit color va...

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ERIC-1: Homebrew Computer Part 1
Everyone seems to be building their 6502-based 80s esque computers nowadays, and it seems to be a lot of fun. Well, I don't want to miss the party, so I've recently started building one of my own. I've now been working on the thing for a few nights and here...

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Driving a RGB LED with Arduino Uno
Here's a simple way to drive a RGB LED with Arduino Uno. The microcontroller generates a multiplexed PWM signal in software. The PWM is generated in an interrupt routine so the main program and LED update frequency are completely independent. The only requi...

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VIC-20 Flash Memory Programmer Part 1/2
My first computer was the Commodore VIC-20 which my dad bought me when I was something like 7 years old (thanks dad!). VIC-20 is the predecessor to the mighty Commodore 64, the most popular microcomputer ever. VIC has much the same feel as the C64 and both ...
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