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Post Ax4d4Ik6LZqiY86Zgu by [email protected] |
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More posts by [email protected] |
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Post #Ax4RLA36iuWT3nGfj6 by [email protected] |
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oh hello copy protection, fancy meeting you here |
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Post #Ax4RVeY6BFX0Y8lbH6 by [email protected] |
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@foone MFM mentioned!!!! |
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Post #Ax4RVeftiFlmwKPpQm by [email protected] |
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@49016 NOT THAT MFM |
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Post #Ax4SLU6EHCwPCQRj3A by [email protected] |
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oh hey that's fun. this game has two layers of copy protection! if I hack t… |
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Post #Ax4Sd9fWyYoD30NsbA by [email protected] |
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they call the copy protection on two different sectors, and throw the out-of-ph… |
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Post #Ax4Sg7Mlzd8Mm71UuG by [email protected] |
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so you can't just overwrite check_copyprotection_sector with return 0 |
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Post #Ax4SsJPl1YitcIEYW8 by [email protected] |
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oh god they overwrite the DOS interrupt 1E in the middle, to make DOS think it&… |
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Post #Ax4T6Ugptnfednz6fo by [email protected] |
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@foone which game? |
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Post #Ax4T6UnDW4m6xayCcS by [email protected] |
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@psiie Rogue |
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Post #Ax4cMFl458uKYGYHXE by [email protected] |
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okay I now know HOW to crack the game, I just gotta write the x86 assembly. |
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Post #Ax4cPvoUB77LqtuEWO by [email protected] |
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normal people don't do this. normal people don't write 16bit DOS assemb… |
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Post #Ax4cZPTvF232TOo76W by [email protected] |
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@foone .... but I do have a book about it! |
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Post #Ax4cymOfBFUSmbRcnI by [email protected] |
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@foone seems perfectly normal to me. its only a few weeks ago that i was writin… |
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Post #Ax4d4Ik6LZqiY86Zgu by [email protected] |
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@foone "Normal" went out the window a long time ago around here. |
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Post #Ax4d81I5Ath1a7lxaa by [email protected] |
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I have 37 bytes. this won't be hard |
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Post #Ax4dfN92wTEauxRwcC by [email protected] |
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@foone don't be normal. Totally overrated. |
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Post #Ax4diwCZ3gMYVrnNHU by [email protected] |
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@foone Fun people on the other hand... |
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Post #Ax4eVFq9LWbVJwLmIC by [email protected] |
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and... it doesn't work.tertiary copy protection? |
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Post #Ax4eZeQNsrCoj5OYXA by [email protected] |
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I think they might be depending on the value of the weird sector elsewhere. lik… |
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Post #Ax4f75rgsjmxO578Ou by [email protected] |
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@foone why |
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Post #Ax4fTWxooGCLntgAZU by [email protected] |
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@foone Security via obscurity is a _type_ of security. |
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Post #Ax4fWktTTVYlsLBWZE by [email protected] |
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@foone Remind me so much of old 68k protections on late ST games. Jay it works.… |
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Post #Ax4fmtwFc9YcYpBNMu by [email protected] |
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@foone True. Last time I wrote 16 bit DOS assembly was last year.It was to dete… |
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Post #Ax4gcncKMVhS0ubu5I by [email protected] |
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I need a comparative DOS CPU tracer. Like, load two copies of the same EXE, and… |
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Post #Ax4hMYiS63IL7SIM0O by [email protected] |
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@foone Cosmic ray detection? |
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Post #Ax4hZtDBCofWRx1YZs by [email protected] |
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@foone well that's significantly more complex than my cracking of X-Wing (o… |
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Post #Ax4kuNbcD6wIMyuq1o by [email protected] |
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@foone actually that would be pretty rad! |
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Post #Ax4llhU91tKZNAqYN6 by [email protected] |
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@foone sync function stepping between two DOS boxes and xor the output? |
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Post #Ax4lrUt2mbYk2MG0WW by [email protected] |
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@foone Your reference point for normal people seems to have become like https:/… |
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Post #Ax4mq2l1yti8SbNcDg by [email protected] |
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THEY CHECKSUM THE FIRST 16KB OF EXECUTABLE RAM? |
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Post #Ax4nAIKXn8oiYAeCJM by [email protected] |
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I patched the EXE to have the right value, but then they checksum it, and now t… |
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Post #Ax4nDIn0Xc6SqJOYV6 by [email protected] |
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insert pop-team-epic "you are motherfucker" here |
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Post #Ax4nJXkvoDOIzwOrUe by [email protected] |
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they checksum memory MORE THAN ONCE!? |
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Post #Ax4nZ0J5wHwftJkfkO by [email protected] |
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@foone they were VERY serious about their anti-piracy and anti-cheat measures. |
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Post #Ax4ncT6nJOr65QeNvM by [email protected] |
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@foone 🎶 Too many sums, too many sums… Too many sums, too many sums… |
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Post #Ax4nhq49NtbSjeyTXE by [email protected] |
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I patched out the checksumming and I think I've got it. |
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Post #Ax4nsTMi7p13W3j6SO by [email protected] |
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@foone I am behind seven checksums, I am uncrackable. |
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Post #Ax4orpcA19e2BYD9fM by [email protected] |
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okay, so, the copy protection:1. It checks for a sector that should not exist: … |
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Post #Ax4oyEWCL3lXA1TUzQ by [email protected] |
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@foone They probably studied at the California Institute of the Arts: https://e… |
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Post #Ax4p9NynVCDrgpAb0C by [email protected] |
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so step one to bypassing the copy protection is hack that function to return &q… |
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Post #Ax4pv14ZyKT6XtaPUe by [email protected] |
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the next phase of copy protection checks another sector: track 39, sector #25. … |
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Post #Ax4pzJyncRUYLHw43M by [email protected] |
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Here's what track 39 looks like. |
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Post #Ax4qaZ0khA1NfzbjAO by [email protected] |
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I think there's another layer of protection that I bypassed on accident |
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Post #Ax4rXNMReZlMd5nXAe by [email protected] |
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@foone I remember writing a TSR for an ATARI that would intercept the disk I/O … |
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Post #Ax4vjTHNsHVAHDSC8G by [email protected] |
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trying to figure out this possible third layer of protection before I continue.… |
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Post #Ax4wDqTYCD4yuEd01Q by [email protected] |
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okay, tracked it down: it's just coming from the same sector 113 as loaded … |
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Post #Ax4wH5XOeUaQUMyPQG by [email protected] |
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but if you apply these two patches, it'll STILL not work! But it won't … |
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Post #Ax4wUMjE343pZNpyca by [email protected] |
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But at the end of the game, it'll change your tombstone, and not save your … |
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Post #Ax4wc7ymljJE8voh9c by [email protected] |
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that's because the checksum failed. it checksums the the code segment, star… |
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Post #Ax4wvTyxBgSjsx7m1A by [email protected] |
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fun fact: this code is self modifying! not for copy-protection reasons, but for… |
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Post #Ax4wycij9gLfr624Ia by [email protected] |
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but luckily for everyone, the call_interrupt function is at 1000:e3b6 so it'… |
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Post #Ax4x53c84v9L0B0vuS by [email protected] |
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@foone I rather appreciate that you end up being able to play and still get not… |
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Post #Ax4xCSOAMfi5rn0lN2 by [email protected] |
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so, step 3: The checksums.I hack out the checksum function so that when it'… |
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Post #Ax4xMfeLunm7tIS7yy by [email protected] |
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so I have a hack that works: I don't think I trust it though. I'm going… |
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Post #Ax4xZI4cslRUXEl9VI by [email protected] |
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rather than hack my way into having a disk that'll work when mounted in DOS… |
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Post #Ax4xl8EFJLGdTcuCP2 by [email protected] |
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weird. I can't find any DOS file interrupts. I know this is for DOS 2.x, bu… |
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Post #Ax4xoB8mwOCbNQo0dU by [email protected] |
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oh wait I searched on "int 21h". but there's a generic interrupt … |
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Post #Ax4y5uroBYDk7JJyt6 by [email protected] |
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@foone Rude. |
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Post #Ax4yU5ilTufMjLcQPA by [email protected] |
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btw, the game (Rogue, if I didn't mention that before) is written in C, and… |
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Post #Ax4z5g8X3HisNzau3M by [email protected] |
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@foone The only version I have (and had back then) is cracked so it's inter… |
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Post #Ax4z8vHhBnU2EcQYk4 by [email protected] |
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@foone the way you solve TOCTOU is to add more TOC |
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Post #Ax4zTalmephOgtMAzI by [email protected] |
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this game is so old it doesn't support directories |
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Post #Ax5071093xMvLAs9gW by [email protected] |
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@foone so just make the last instructions in the checksum code return the value… |
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Post #Ax54k8XHNpupooHTEG by [email protected] |
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@foone I am here reading your posts. I hear and understand. |
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Post #Ax57ZinIXF02wtUyYK by [email protected] |
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okay I understand enough of the IO system to write this code, but I haven't… |
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Post #Ax57qNtNV8eb2tHuwi by [email protected] |
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@foone ...And a nap. |
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Post #Ax5fjvlMZLqUVZdK4W by [email protected] |
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@[email protected] I was thinking about that just the other day, trying to re… |
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Post #Ax5fmX4OpjjinEmIb2 by [email protected] |
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@foone checkmor, if you will |
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Post #Ax5fwgcs9w3JKIkD9k by [email protected] |
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@foone Another one for the death generator? |
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Post #Ax5g41lRxwGaufFzCC by [email protected] |
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@Dianora @foone yes so much channeling of those memories… whoops how did that… |
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Post #Ax5gdNxHS8B5s7eNxg by [email protected] |
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@foone I played this as a kid! Off a floppy |
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Post #Ax5ytiTEk7jDJ8XCWu by [email protected] |
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@foone Oh I remember asking you about this ages ago, you said it was really rar… |
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Post #Ax69ZHWeJT2dRYaaw4 by [email protected] |
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@foone is this repeatable? i'd like to fix any crashes :) |
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Post #Ax69ZHdjt6iFnXuFzE by [email protected] |
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@gloriouscow sadly not. I had it running on my secondary monitor and I think th… |
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Post #Ax6NOwCi87kNmJE0tk by [email protected] |
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@foone Can you make the Unicorn more friendly? |
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Post #Ax6V91Lk1voSjlN0tM by [email protected] |
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@foone oh yeah that's a wgpu error. not much I can do about that :( |
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Post #Ax6YX5S6jBXQH2W000 by [email protected] |
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@mos_8502 @foone normal people obviously don’t know how to have fun then |
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Post #Ax6qqrYxsOAOABIn9k by [email protected] |
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@foone I write 16bit BIOS assembly in 2025 does that countIt's close enough… |
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Post #Ax6qtg9qjj3hextho0 by [email protected] |
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@ity yeah, close enough! |
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Post #Ax6r0DPS1LBMWdJNqq by [email protected] |
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@foone what about PCBox |
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Post #Ax6r8gVzgtMV6xPWRE by [email protected] |
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@ity haven't used it. I've already got 86box and I don't know if PC… |
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Post #Ax6rGfx3fa8BgEscqW by [email protected] |
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@foone ah, fair nuff :3 |
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Post #Ax7UdOd68PpcpWMvPU by [email protected] |
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@foone oh God that padding isn't just general stack space being used (inter… |
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Post #Ax7bcx6bAV3T90u2Gu by [email protected] |
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@foone @ity PCBox is a fork of 86Box that started because 86Box devs didn't… |
