Pokémon Red/Blue - analysis of basic crash types
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- Опубліковано 28 чер 2022
- We all know that Generation I is glitchy, and the game might crash as a result of all that glitchiness. Turns out, there are a lot of patterns in the types of crashes you can encounter. Let's investigate!
- Ігри
i'm apparently not dead lol
alive!
Reminds me of a
Yoooo you are back.
Apparently.
i love you
Sounds like “look at normal Pokémon before attempting glitch” is a good idea in general, not just for dealing with faulty emulators.
Yeah, ZZAZZ posted a video a while back showing off a "make your own trainer" glitch where you could change ZZAZZ trainer 0xFC's first roster using glitch Pokemon. He stressed that you should always look at a non-glitched Pokemon's sprite before encountering 0xFC, because if you don't, its entire party will be level 255 Charizard 'Ms
kinda hilarious how common "overwrite the entire memory" is in these games
It just needs an accidental infinite loop :P
@@cmyk8964 Which is like 2/3rds of how a crash occurs.
@@cmyk8964 Yeah lol, all it needs is a write command inside an infinite loop
More nerd stuff, explaining the STOP instruction:
The actual opcode is just 10. However, there's a bug in the GB CPU (might be fixed in GBC?) where it will read the byte following this opcode twice. So if you did something like "stop; inc a", it could increment twice; if you put a multi-byte instruction there, it would be read incorrectly.
The official fix for this was to pretend "10 00" is the opcode for STOP, since repeating a NOP is harmless, and "10 xx" where xx ≠ 0 is undefined behavior.
This also applies to HALT. That's sometimes called the "double halt bug" since if the instruction immediately after HALT is another HALT, it can get stuck there forever.
That's not entirely correct. In the usual case, the second byte is entirely skipped and not executed at all. You can have an invalid instruction in the second byte and the GB would run fine usually. In some cases it is executed, but generally that won't happen (and there is never a "double read" here). The "double read" you refer to only applies to halt, stop does not have this issue.
Also, the "double read" only occurs when halt mode is entered while an interrupt is already pending due to rIF and rIE (although ignoring IME here). It's also in reality not a "double read" but rather an extraneous decrement to the PC (so when IME is disabled, it "double reads" the next byte, but when IME is enabled, it instead causes the return address of the interrupt to point to the halt rather than the opcode after halt, the latter case being rare of course given that means rIF would have to change at the exact cycle you enter halt, that or IME is enabled on that cycle (nice for testroms given ei's delay)). Also, of course, due to this, halt after halt doesn't mean it will always be stuck forever (just "can").
You can check more info on STOP on the pandocs here (which includes details on the quirky cases): gbdev.io/pandocs/Reducing_Power_Consumption.html#using-the-stop-instruction
HALT? Are you talking about the Doors HALT?
halt and catch fire
@@Curioust2020 there is no saving humanity
@@Curioust2020 "There are approximately 1,010,300 words in the English language, but I could never string enough words together to properly express how much I want to hit you with a chair." -Alexander Hamilton
Oh wow, I remember back in 2007 when I first saw videos on the TMTRAINER effect that I was spending countless hours trying to figure out a way to not make it crash and I discovered that you could do that glitch in the seafoam island cave east of cinnabar island without it crashing. At the time, it seemed to be the only area that it worked but now I know that it's because there are no NPCs in that cave. Thanks for the info
5:44 I lost two VC saves from mishandling glitch items due to this. Good, if a little late, to know there's actually a way to prevent that.
RELATABLE
i tried doing yami shop glitch at the celadon dept store(yes on a 3ds vc on red), but even though i did the steps for it correctly, my game still crashed and save data actually just got erased entirely. Luckily, even though i didnt like my save being erased, that meant i could do the save corrupt glitch (or whatever its called) to get myself champion in 1 min lol
Welcome back! You've been a massive inspiration for me to learn reverse engineering and programming and I'm glad to see your videos again.
Same
Same!
This here is my answer to questions of the kind "Why are you wasting your time digging into old video games?"
Because these can serve as excellent "toy"* models for learning skills like assembly level debugging, understanding memory corruption, and reverse engineering.
All of these are immensely useful skills of real world computer science.
Plus, the "old video games" have a nice, fun incentive for you to learn about these skills, until you start to find the skills themselves to be interesting and motivating enough in their own right.
* or rather, real architectures, but simpler than modern counterparts which are much harder to understand when learning from scratch
Yes a big deal, just reset
Yes only can they
That RST 38 crash fills me with an inexplicable amount of dread.
Have been re-watching your videos and somehow manifested a new one! Also FINGER REVEAL AND ZZAZZ ISN'T A SKELETAL AERODACTYL IRL WHAT???
We had a hand reveal in the lua script video if I recall correctly
Hey, I'm not the only one!
The hands and feet are human, the arms and legs are Aerodactyl bones and the rest of the body is RST 38 stripes
Honestly, Game Crashes just intrigue and fascinate me; just seeing the game fall apart or react in a different way due to an unexpected event is so much fun and I love it when crashes are explored in depth as to what's happening behind the scenes. I'd *_love_* for more Game Crashes (maybe not even just Pokémon, but in other games) to be explored as to what happens, how they happen and what the outcome could be
Stryder7x has tons of stuff like that.
I feel the same way, subscribed to both channels. If anyone knows channels like these, please let me know
@@brightcolorsarecool279 Can confirm, and I can't wait for when he uploads again. His last video was like three or four years ago
Tactical handwarmers for optimal pokemon gaming
TheZZAZZCycle
1: Upload video
2: "not dead lol"
3: Dissapear for 8-16 months
4: Repeat
There was a technical analysis shaped hole in my heart.
That aside about corrupting a _different_ game's SRAM sounds fun... particularly if there's any games that don't notice the corruption and actually treat it as valid data, somehow. Though like you said there's a lot that could make the whole idea not work at all.
that's what makes the paper mario ACE/ASE work, so there's absolutely potential.
Crystal_ did something similar a few years ago
Isn't that a strat for Mario Land 2 or something?
@@reddodeado301 no, it's just work RAM that's being corrupted in that strat, not save RAM. Save RAM is harder because there's typically a checksum or similar so the game can detect a dead battery.
Yes only can they c save data!
Welcome back, ZZAZZ! Was having an *especially* terrible day and all my favorite content creators suddenly started uploading today...
Glad you're providing us with that nice glitchiness again :)
hope you're having a better day today
That's really freaking cool! Very nice to be able to explain why some outcomes are more dangerous for the game than others are
yo your also alive! i hope your still doing fine
11:21 I love how you can hear the great harmony for Pallet Town really clearly here. This has nothing to do with the video, I just thought it was neat.
16:11 turning your entire memory into the start menu is the ultimate form of Start9
StartOver9000
It always warms my heart to see another ZZAZZ video. Can never associate the Lucky Channel OST with anything else in my head after all these years
I’m pretty happy the video was slightly more beginner friendly as while I know a small amount of programming and video game tech, I don’t know anything about low-level programming languages or where hex value data goes. Giving an explanation of what certain hex values do what helped a lot!
The RST 38 glitch at 8:10 was so melodius :') Can we have a musical glitch episode ? It would be interesting 😁
Maybe check out “chip furnace” they have music created from corrupting the memory in video games.
@@drdca8263 Indeed, not bad but it's only lightly corrupted. I prefer completly new music from hard glitch (for exemple the cursed musique in the japanes version of pokemon green when you mess with the professor Oak's package and you exit the Map through a glitch in the wall)
@@Arvo-1 That sounds like the Dokokashira Door Glitch
Delighted to see another upload from you!! This is a fun one, I genuinely love hearing about specific reasoning behind glitch stuff like this. (And how the VC emulator being terrible is still relevant...)
"In fact, some types of crashes have been given specific names by the community, just because of how common they are."
Game Freak: *monkey puppet meme*
14:05 The reference to Ace Attorney had me rolling
Fascinating video as always! Glad to see you're back :]
it took me several rereads to spot it, you have eagle eyes
The miracle never happen!
@@theyofmanynames But maybe it was never meant to, because a "miracle" doesn't exist... LOL
Holy crap, I thought I was the only one who saw that! It took me a few seconds to realize that yes, it *was* in fact an AA reference and not just a typo.
Just when the world needed him most, ZZAZZ returned.
I'm gonna call those programmer arm socks and nobody can stop me
I don't think anyone is gonna stop you at this point
the femboy allegations are seeming truer than ever
I always love seeing zzazz in my notifications. I always learn something new and usually interesting
Another amazing and insightful video! Glad to see you back! 💪
Siema arhon uwielbiam twoje filmy
Welcome back, ZZAZZ. You're a legend and an inspiration to glitchers everywhere, including myself when I first got into RB glitching 5 years ago. You rock, dude.
Apparently I'm so into Pokemon glitches that I'll watch someone crash a game for 16 minutes!
I just wanted to say how much I appreciate you working on this channel. It's so utterly unique and interesting, it's always exciting to see what you've discovered in these games. Thanks so much for all the crazy information!
Oh, man, I remember being a kid and just learning about glitches while everyone was trying to figure out how stuff worked. And now, I get to actually understand everything that's going on and keep up with every technical bit that's mentioned, while people that spent years researching the Game Boy figure out exactly how the glitches work in Pokemon. Even the fact that we can have a memory editor is a massive technical breakthrough.
Love the video! I'm super interested in tech stuff, and you explained everything in a way I could follow along with, despite not having seen any of your videos before. Wasn't expecting the arm warmers, but they were a nice touch !
Welcome back! It’s kinda nice testing all kinds of errors/glitches the old Pokémon games had :)
seeing your uploads never ceases to put me in a better mood, thanks for creating ☺️
This is an interesting topic that I've thought about many times in the past 20+ years. Great to see a video about it, and by the master no less
Just started watching a bunch of your videos recently, what a treat!
It's pretty amazing to see that you're still around. I remember watching your videos wayyy back in the day. Missingnoxpert is long since gone but you're still holding up. Keep up the good work! 👍
Great vid as always 😎, the way you explain every part of what's going on is really interesting and helps us understand and and it's really cool.
welcome back!! this was super interesting and informational, great for the end of a long work day
Always nice to see a ZZAZZ video. I've spent a small amount of time every once in a while trying to see what weirdness occurs in glitching things with the 3DS VC, losing many saves in the progress. It was only a few days ago I actually just got my 3DS setup to use Checkpoint so I could at least start backing up my saves. Great job explaining showing and explaining the RST crash, makes it pretty easy to understand.
Welcome back! It's great to see videos again and the technical analysis behind it. The added sprinkle of memes/humor/sound effects keeps it from being "boring" - not the actual definition, but basically adds a little spice to keep you entertained while learning what's going on under the hood.
Very glad you're still around! Randomly got the urge to look up your channel again, seeing the recent upload was really cool :)
YOOOOOOO good to see a new video from you! Love your arm warmers btw :3
I'm glad you're not dead. Your vids are a really interesting peek behind the curtain of code.
I love these videos they're highly informative and presented visually well. Glad to see more.
Very interested in the corruption of another cartridges SRAM while RST38 is a ctive in a scenario when a game's bank is left vulnerable by default.
I feel that it would mainly work with older titles, and that later titles would be less prone to RST38. GBC titles especially would most likely be quite immune to the effects, and titles that don't support the original Game Boy would probably only show their respective GBC only screens.
I feel like you're the only one that puts good editing in these kinds of videos. Usually glitch channels record on source 480p and add some text on a black background. The only thing missing off of yours is voice over and i can fully binge watch them
Happy to see you back! Great video as always!
It's been so long! I love this type of stuff
Very appreciative of the work put into the explanations. Thank you.
I always have silksong levels of hype for your videos
Usually if the LCD is turned off outside of the VBI you’ll see a line or two. If left like that for too long I suppose it may cause damage, but if you power cycle the Game Boy quickly after seeing that it’ll usually be just fine.
(This effect is only visible on monochrome Game Boys; the GBC screen just goes blank AFAIK)
Welcome back! I would love to see a video on glitch sounds and how the game decides what sounds to play
So glad to see you're back, ZZAZZ! My sibling and I don't really share many common interests, but Pokemon glitching and your content in particular is something we can both agree on. Happy to have a new video we can discuss together, and I'm hoping to see more from you in the future! Fantastic video!
Need a video on "fixing" crashes, where the game crashes but with a memory editor either remove the erroneous bit of code that caused the crash or repair it then we can see the game can keep running beyond the crash. If I am not mistaken, I believe you did similar before with one or more of the glitch pokemon or was it glitch move/item, but would be nice to see more.
Well, it would depend on the type of crash. But rarely is just a memory editor going to be enough to recover the CPU, you're going to have to modify the registers and the stack----which would probably require the use of an emulator.
your channel is absolutely fascinating. automatic sub, hope to see more of your work soon!
Yooo i missed you lol, finally some quality pokemon glitch content again. Good to see you arent dead
"Infinite sleepy time" is both hilarious and terrifying terminology.
Welcome back! Please bring back more PMD videos. Im still patiently waiting for them
I picked a good time of the year to just rewatch your videos.
EDIT: I remember the Pokédex entry at 11:50 from a MissingnoXpert video. Good memories.
welcome back!!! you inspired me to get into this stuff :O
always glad to see a new upload from you
I knew my clock was messed up. setting it back to april 1 now, thanks ZZAZZ
welcome back! always a great day when thezzazzglitch uploads :D
I noticed the Phoenix Wright reference, barely caught it because "never happen" turns on my brain cells.
7:20 "No no no, bad. You'll lose your save file. Do this instead."
Welcome back! Love your arm warmers :3
Yoooo welcome back!! This was an interesting one. Learning about the potential for RST 38 to have unknowingly caused 4 4's true cry... It seems that mystery will Never truly die and I can't say I blame you. It's fascinating
interesting and also entertaining
i like how the biggest reason for lockups was just the game trying to divide by zero lmao
Always makes my day when TheZZAZZGlitch uploads ^_^
I missed your channel!! Hurray for more videos :D
When I got the notification on my phone that there was a new video from you I literally said "YOOOO" out loud
Welcome back!
Very nice video! I've done a little bit of tracing through an rst 38 crash breakout case before, I might have to revisit that
A new ZZAZZ video is one of the most wonderful, unexpected things to wake up to.
Watched all these videos and I still don't understand what a bunch of it is, but i see my childhood game get torn apart from the inside and its fun to watch
It’s good to have you back.
Arm warmers detected???
YOOOOOO
Great to see you back!
YES. I love learning about funny hex numbers that cause games to go crazy mode!
the legend is back
A new video? welcome back! Nice to see you besides the april videos
I hope the mistery dungeon videos are coming up nicely
So glad you’re back
i’ve wanted this for no reason and am so hype
oh my gosh i was just watching your videos yesterday!!!
Babe wake up new ZZAZZ vid just dropped
The Return of the King
hah! Welcome back ^w^ glad to see you are doing alright
Looking forward to seeing the results of RST 38 cartridge swapping if/when you get around to it!
can't wait for a needlessly deep analysis of the rst 38 crash 🙂
seeing "unknown opcode" combined with the gen 4 berry noise just gave me missingnoxpert memories
> My whole memory is now start menu. I hate when that happens.
At least you won't forget that you need to start!
Return of the king
The fact that you can glitch yourself to a perilous state and then re-set your corrupted state is amazing
i've always liked your videos!
1:37 it seems like @TheZZAZZGlitch is part missingno with the stripey appearance from sprite decompression and causing game corruptions. It seems to have read some actual sprite data when rendering though meaning that the sprite data pointer was close enough to real data to render some. Also, the width value used when rendering is correct for the real sprite data it read.
The beast is back
The return of the king
Glad you're alive!
dude i finally have an answer for my deleted yellow save file on my 2ds. Thank you so much, love your channel
This is the 1st time I've heard the phrase "undefined behavior" used when talking about machine code. A vid on when UB occurs would be cool