• Video demo of the Pi acting as a disk drive

    04 Aug | 13
    • in Commodore 64 • 
    • by Chris Osborn

    I've made some more progress on my software that allows the Raspberry Pi to act as a Commodore 64 disk drive. I was amazed at how much more of the IEC protocol was missing from the documents I have. One of the things that I found a little strange about the IEC protocol was there was no way to specify how much of the data you want. Once you say go, the sender is just going to send it all. It turns out that when ATN is asserted it doesn't mean abort , it just means pause. Took quite a...

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  • Making a Raspberry Pi into a unified retro peripheral

    21 Jul | 13
    • in Raspberry Pi • 
    • in Commodore 64 • 
    • by Chris Osborn

    If you've been following along here or on Twitter or Google+ you've no doubt seen the experimenting I've been doing with interfacing a Raspberry Pi in various ways with several retro computers like the Atari 800 and Commodore 64. My first project was using the Raspberry Pi to act as a converter for a USB gamepad to turn it into an Atari 2600 style joystick. After discovering Eric Nelson  on Twitter and seeing all the games he was playing on the Commodore 64, I really wanted to...

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  • Wow is the Commodore 64 bus slow!

    20 Jul | 13
    • in Raspberry Pi • 
    • in Commodore 64 • 
    • by Chris Osborn

    Got the kernel module for the Raspberry Pi that does the Commodore 64 IEC protocol working quite well. Managed to get rid of pretty much all the timing issues, and cobbled together a simple user space program to handle the file I/O. I can now read & write PRG files, even very large ones. It was interesting sending a file (by accident) larger than the C64's RAM, the poor C64 freaked out and overran even the screen and crashed. It was very cool to load a Demo without having to mess...

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  • USB Joysticks and Retro Consoles

    07 May | 13
    • in Raspberry Pi • 
    • in Commodore 64 • 
    • by Chris Osborn

    One of the things bugging me while tinkering with old computers has been the joysticks. Several of the computers I'm playing with can use the Atari 2600 joysticks, but those joysticks are awful. I've never liked them, even back when the Atari 2600 was new. I kept thinking about getting some other 2600 compatible joystick, or maybe making a box and sticking some of my arcade buttons and joysticks in it and wiring it up with the 9 pin Atari pinout. Neither of those ideas seemed...

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  • Turning a Teensy into a floppy controller

    04 Apr | 13
    • in Electronics • 
    • in Commodore 64 • 
    • by Chris Osborn

    If you've messed around in the Commodore 64 world for even a short time, you've probably discovered that it's theoretically possible to hook up a Commodore 1541 5.25" floppy disk drive to a PC. Most of the information you come across though either talks about a specialized circuit board, or using a computer with a parallel port. While I do have plenty of older computers that have the nifty parallel port that can be used as GPIO, I was more interested in interfacing the drive...

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