Monthly Archives: December 2020

A tiny Christmas present

Back in August this year, E$G asked me whether I’d be willing to come up with a facility to let graphic artists in Hokuto Force add raster bars to their C64 artwork. I guess the idea came directly from a … Continue reading

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Flux Studio: progress update

I chose to make a video to show a comprehensive list of “official” features currently available in Flux Studio 0.8: One thing that I should investigate is the actual structure and purpose of the unusual t/s 18/16 in later Vorpal … Continue reading

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One last look at later Vorpal disks

Inspired by the recent exchange with Mr. Laufwerk, I decided to share a few pictures that show how tracks are mutually aligned in a few later Vorpal disk images. None of the disk images I used were realigned: they show … Continue reading

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Vorpal disks: lead-in and trailing patterns

As the question was asked, here you find a visual representation of the lead-in and trailing patterns in original disks that use the later version of Vorpal: From left to right we see: trailing sequences lead-in sequences Worth noting: even … Continue reading

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Vorpal disks: perhaps the most reliable way to set write splice offsets

By now my readers should be familiar with the fact that one of the most severe risks involved in writing the data of a protected disk image back to a floppy disk consists in starting (and ending) the write operation … Continue reading

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California Games: Yet another Easter Egg

It appears to be generally known that all Epyx “Games” contain one form or another of Easter Egg, so it should be no surprise that California Games does too. When I finished my Vorpal data decoder and shared the news … Continue reading

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Flux Studio: all Vorpal blocks can now be decoded

I finally also finished implementing the decoder for custom Vorpal blocks on track 18. There are four of these in California Games, used to load the main drive code into the drive RAM. Here’s the debug output from both Vorpal … Continue reading

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Flux Studio: progressing with the development while dissecting Vorpal

My current efforts with Flux Studio when it comes to Vorpal are twofold: create a data decoder in order to check the integrity of G64 images (similarly to what TAPClean does for TAP images) detect at which point in a … Continue reading

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Dissecting the Vorpal (later) disk protection – part 1

Update to this post: California Games does NOT load the main drive code from track 17.5 or 18.5 as previously stated. It loads from track 18.0 as the stepping instructions detailed below just step outward and then back onto track … Continue reading

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How the block-sync and byte-sync signals of a Commodore 1541 drive work

If, like myself, you decide to delve into the mythical world of disk copy protections for the Commodore 1541 drive, you might find out that useful reference documentation is a tad scattered all over the place. In fact, I haven’t … Continue reading

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