Post subject: What's a save state?
Joined: 5/30/2007
Posts: 4
I know by asking this question it makes me probably sound like a noob but I really don't know what a Save State is or how to use them...It's confusing me...can anyone give me answers or tell me how to use them... And if this was already posted...then sry for not looking around more... Thanks for any help!
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top of the page wrote:
If you have a question, please read the FAQ first to see if your question has already been answered.
Just do it.
Warp wrote:
Edit: I think I understand now: It's my avatar, isn't it? It makes me look angry.
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http://tasvideos.org/Glossary.html#savestate_ Depending on what emulator you're using, there are different ways to save and load savestates. Don't forget that the FAQ is your friend.
hi nitrodon streamline: cyn-chine
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A miserable little pile of secrets.
Player (150)
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'Savestate' is just a colloquiallism for 'saved state'. State in this context refers to the 'condition' of the emulated console. When you load a state you should be at the exact same moment as when you saved it.
Nach wrote:
I also used to wake up every morning, open my curtains, and see the twin towers. And then one day, wasn't able to anymore, I'll never forget that.
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RT-55J wrote:
'When you load a state you should be at the exact same moment as when you saved it.
Yes normally, "you should" but it's not always true.
Mitjitsu
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I'm actually curious as to whats exactly stored within each savestate, since surely you would need to store the characters postion motion, acceleration, room state, and possibly many other things.
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A saved state is just a dump of the console's RAM.
Nach wrote:
I also used to wake up every morning, open my curtains, and see the twin towers. And then one day, wasn't able to anymore, I'll never forget that.
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It also includes all the memory for other hardware, like the sound, graphics, etc. Also, the CPU's registers, mode, etc. Also, in movies there's movie information stored for rerecording. Basically any piece of hardware that needs to do work over an extended period needs its state saved. SRAM is often tossed in as well. Etc. Etc.
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Atma wrote:
A miserable little pile of secrets.
No, that's a man.
Warp wrote:
omg lol this is so fake!!!1 the nes cant produce music like this!
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Dracula is Cardboard! ...But that doesn't make any sense. o_o
creaothceann
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AKA wrote:
I'm actually curious as to whats exactly stored within each savestate, since surely you would need to store the characters postion motion, acceleration, room state, and possibly many other things.
Savestates are not game-specific (means: they store everything and don't care about character positions etc). In the FAQ there's a list of file extensions (FMV, VMV, FCM etc). The linked pages show what each movie file type contains - sometimes also a savestate. The source of the emulator should show what is saved in one. Btw. RHDN has the old ZST format.
Emulator Coder, Skilled player (1310)
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For most practical purposes they are game-specific, in that you usually can't expect to load a savestate in a different game and continue playing in any meaningful way, and the state of the ROM is arguably part of the emulated system you're intending to take a snapshot of even if isn't directly stored in the snapshot. Also, cartridge-based games often include their own additional hardware (especially NES and some SNES games), which must be represented in the savestates.
AnS
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BTW, is there any kind of documentation on FCS format somewhere in the Internet? Same question with VMV and Snes9x savestates.
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AnS wrote:
BTW, is there any kind of documentation on FCS format somewhere in the Internet? Same question with VMV and Snes9x savestates.
fceu/src/state.c virtuanes/something/equivalent.c snes9x/snes9x/savestate.cpp I.e. besides the source code, highly unlikely.
creaothceann
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-> vSNES source/uS9X.pas Files are usually compressed via gzip, can be extracted with WinRAR etc. The gzip library can also read transparently from uncompressed files.
file header:
 - Signature (8 chars)
 - Colon     (1 char )
 - Version   (4 chars)
 - Delimiter (1 char )
Files are organized in blocks which come after the header.
block structure:
 - Name   (3 chars     )
 - Colon1 (1 char      )
 - Size   (6 chars     )
 - Colon2 (1 char      )
 - Data   ([Size] bytes)
Required block order:
"NAM" (cartridge name)
"CPU" (CPU status)
"REG" (CPU registers)
"PPU" (PPU status, basically registers $2100+ with some modifications)
"DMA" (DMA registers)
"VRA" (VRAM)
"RAM" (WRAM)
"SRA" (SRAM, always $20000 bytes)
"FIL" (FillRAM, 32 KB storing the last values of the registers $xx:0000..$xx:7FFF, regardless if mapped or not)
"APU" (APU status, optional)
"ARE" (only if "APU" is present: APU registers)
"ARA" (only if "APU" is present: APU RAM)
"SOU" (only if "APU" is present: other sound data)
"SA1" (SA-1 status, optional)
"SAR" (only if "SA1" is present: SA-1 registers)
"SP7" (SPC7110 status)
"RTC" (S7RTC status)