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One of the most interesting copy protection techniques I came across was on the Atari Microsoft Basic disk. You booted this disk and it automatically loaded into Microsoft Basic. If you then typed a DOS command, you were taken to the usual DOS menu where you could see an AUTORUN.SYS file. But if you copied the AUTORUN.SYS file to another disk, it wouldn't load into Microsoft Basic. It started to load but then simply performed a system reset. It turns out that the clever programmers at Atari created a hidden directory on the disk. Normally, the directory is found on sector $169 and runs for 8 sectors. On the Microsoft Basic disk, there is another directory at $179. This directory points to the real AUTORUN.SYS file which loads when the disk is booted. At address $1082 in the Disk Operating System there is a byte which points to the directory sector. The value of this byte is usually $69. But in the Microsoft Basic version, the byte is $79 which allows DOS to use the hidden directory and load the proper AUTORUN.SYS. As the AUTORUN.SYS loads, one of the final things it does it to place a $69 back into address $1082. Now DOS is pointing to its normal directory which points to a bogus version of AUTORUN.SYS. To copy the correct AUTORUN.SYS to another disk, you could write a basic program which poked $1082 with $79. Then open AUTORUN.SYS for input. Poke $1082 with $69 to reset DOS back to its normal value, and open an output file on another disk. Now simply read and write bytes until end of file. Poke $1082 with $79, issue a close on the first file, poke $1082 with $69 and issue a close for file 2 and voila!, you have a copy of Microsoft Basic that loads properly. Copy Microsoft Basic.atr
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FLAK, by Funsoft, disk has an almost unique copy protection based on physical alteration of the disk surface. Physical copy protection, as opposed to magnetic ones, are almost impossible to copy. Even modern flux transition level devices, that at least in theory, can copy just about any magnetic based protection, can't copy this type of protection because, obviously, it requires altering the disk surface. The special characteristic of this protection is that survives a write or even a format of the whole track. That means that can't be copied by pure magnetic methods because any magnetic pattern would be overwritten by a write. If the software that checks the copy protection doesn’t write to the disk at runtime, then it can't distinguish a physical from a magnetic protection. It would typically read just as a sector with weak bits. The most common method to perform a reliable physical alteration to the disk surface is with a laser burnt hole. But laser holes require sophisticated equipment and were very expensive to produce. This process was rather expensive and then it was used only for applications usually costing much more than a game. However, a couple of publishers developed affordable inhouse methods. I contacted Yves Lempereur, the original FLAK developer, and asked him how they actually applied the protection. This was his answer that includes a small anecdote: This is the only game we know with this type of protection for the Atari 8-bit. The only other case I am aware for any platform is a British game release for the Atari ST. A couple of pictures of the actual physical modification from two different copies of FLAK, courtesy of two members of the a8preservation team:
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MAME 0.227 It’s time to say goodbye to 2020, and we’re doing that with the release of MAME 0.227, the fruit of our extended November/December development cycle. A lot has happened in these two months, in terms of internal improvements to MAME as well as user-visible changes. If you’ve been following along with development, you’ll have noticed that we’ve migrated MAME to C++17, overhauled the Lua interface, further streamlined and enhanced the emulated memory system, and cleaned up a lot of ageing code. MAME 0.227 adds preliminary support for macOS on AArch64, also known as “Apple Silicon”. Please note that we lack a native A64 recompiler back-end, and there are some issues with our C recompiler back-end. If you’re running an A64 build of MAME, you can disable recompilers for most systems that use them with the -nodrc option on the command line. You may get better performance for emulated systems with MIPS III or PowerPC processors by running an x86-64 build of MAME under Rosetta 2 with recompilers enabled. (Yo, ’sup dawg. I heard you like recompilers…) Lots of long-standing issues have been fixed in this release. Missing platforms in stage 15 of Sega’s Quartet now appear properly. This relies on a protection microcontroller feature that we were previously unaware of. Protection features that are only used late in the game have been a recurring source of frustration not just for emulator developers, but also for arcade bootleggers, and even publishers re-issuing old games in new formats. It seems Sega missed this feature in their Astro City Mini release. Another long-standing protection issue was fixed this month that made Atari’s Rampart impossible to complete on Veteran difficulty. This one was actually a regression that managed to stay unresolved for years, possibly because the game’s high difficulty makes it difficult to reach. While we’re on the topic, protection simulation has been added for the versions of Sega’s Carnival that run on Head On hardware. While protection emulation may encompass the most noticeable fixes, lots of other things that have been improved as well. Graphical issues have been fixed in Chase Bombers, Championship Bowling, and Prop Cycle. NFL Blitz ’99 no longer skips animations in attract mode. DIP switch descriptions have been corrected in 3-D Bowling, Bloxeed and Mahjong Tenkaigen. Game switching now works on Multipede, and Klax bootlegs are playable, with working sound. It wouldn’t be a MAME release without new supported systems. This month we’ve got TV games from dreamGEAR, JungelTac, LexiBook and Senario. As always, the quality varies enormously. New versions of 1944: The Loop Master, Cookie & Bibi 2, F-1 Grand Prix, Forgotten Worlds, and Narc have been found and dumped. One of the newly supported Narc versions is particularly interesting, as it appears to be an early test version, lacking a substantial amount of content found in other versions of the game. Another incomplete copy of Unico’s Master’s Fury was found, which could be combined with the previous incomplete set to make the game playable. Finally, there are a few improvements to the internal user interface. There are more controls for screenshots, aspect ratio and scaling accessible from the Video Options menu. You can now use NOT codes when assigning analog joystick axes to digital inputs. The menus for the Cheat and Autofire plugins have been made more consistent. Of course, there’s far more that we don’t have space for here, but you can read all about it in the whatsnew.txt file, and get the source and 64-bit Windows binary packages from the download page. It’s been a very tough year for a lot of us, but it’s still been a great year for MAME development. Thanks to everyone who contributed this year, even if it was just a kind word or helping out a user on a community forum. Have a great new year, and keep the spirit of digital preservation alive! Read the rest of this entry »
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What is it that you would most like to have but you hadn't seen any for sale yet? One item I think should be made is big specific storage and display cases for each system. Many of us have large collections but need a better way to show off our favorite games. I would love to have large slotted cases designed for certain size cartridges. Nice wooden or plastic racks holding about 100 games would be just great. Another product I would buy in a heartbeat is something designed to clean the contacts on your old school gaming cartridges. They already make those to insert into your Nintendo with cleaning solutions for the consoles & game cartridges. Why the heck hasn't anyone designed one for the Atari, Intellivision, Colecovision etc? What about a cleaning tool, pad, or device that would work on all the smaller hand held gaming units as well? Let's hear your thoughts & ideas on something which you think is needed within the gaming community but you just can't find it in stores or online anywhere.
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I actually play my games, so I need to open the boxes from time-to-time. Opening these thin cardboard boxes without bending the lid a little bit doesn't seem to be my forte. It also isn't too difficult to put wear on the tabs under the lid. Are there any techniques you guys use to open the boxes without putting any noticeable wear on them?
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