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Pocket SNES Advance


blue swIIrl
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Bollocks I'm afraid. I've dabbled in emulators myself a bit and let me tell you you need a CPU much faster than the original to do emulation at full speed. To emulate each instruction of the SNES CPU you'd need at least 4-5 GBA CPU instructions, and in some cases a lot more (I'm not that familiar with the ARM CPU, but as its a RISC processor you may need even more again). Sure you can do some fancy JIT compiler stuff, but that still won't get you there. Add on the overhead of emulating the rest of the SNES hardware as well onto that and you'll see why people aren't getting that excited about this.

The GBA will *never* be able to  emulate the SNES at full speed. As I pointed out earlier in the thread, many people put a lot of effort into doing it on the Dreamcast, which is a very capable system and a powerhouse compared to the GBA, and they only managed to get 1/4 - 1/2 of the SNES framerate in the games I tried.

I know a lot of people start out coding emulators thinking that they'll be able to optimise and optimise again until they finally get to full speed, but in reality what actually happens is you hit a brick wall where you can get the code running no faster.

First of all: you're assuming it's all low-level emulation... it isn't. Hence the huge speed gain.

It is a RISC processor. But the SNES processor is also a RISC processor. This cuts down on the amount of CPU instructions required, since you haven't got to fiddle about with registers as much. Emulating a RISC processor on a CISC platform is much more difficult.

You also compare SNES emulation on the Dreamcast to SNES emulation on the GBA. Bad move - the SNES emulator for DC is a port of a PC application that's running in ported C code rather than native SH4 assembly and it completely uses low-level emulation. If it used SH4 and high-level emulation, I would expect the DC to emulate the SNES at fullspeed however this would require heavy coding. PocketSNES/SNES Advance is being written from scratch natively for the GBA using many tricks. It's a false comparison really. The DC can emulate the PSX using high-level emulation with native assembler yet can't emulate the SNES with ported code.

You also forget that the various graphic modes on the GBA are similar to that of the SNES - makes emulating easier when you haven't got to play around with graphics modes. The DC isn't exactly designed to be a 2D platform afterall therefore the rotation of sprites etc has to be handled by the CPU.

Optimisation also works, as long as you are willing to cut corners. Example of this is Neogeo emulation in NeoRageX and MAME - one requires 200mhz and one requires 1ghz or more. NeoRageX uses tricks, and doesn't emulate everything fully whereas MAME is completely low-level. Yet they both have pretty much the same results... notice the difference?

I say that full speed (without sound) on a large amount of games is an acheivable goal. You wanna tell the authors it can't be done? Post here and see what they say.

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First of all: you're assuming it's all low-level emulation... it isn't. Hence the huge speed gain.

It is a RISC processor. But the SNES processor is also a RISC processor. This cuts down on the amount of CPU instructions required, since you haven't got to fiddle about with registers as much. Emulating a RISC processor on a CISC platform is much more difficult.

CISC/RISC. It's amazing how spouting crap like this can make it seem like you know what you're talking about. :P

The SNES is based on a 16 bit enhanced version of the 6502 chip that powered the C64 and BBC (IIRC) I don't believe that it was a RISC chip (the 6502 certainly wasnt'). But that is entirely irrelevant, the fact is that the SNES CPU is also not binary compatible with the ARM RISC chip used in the GBA, so you have to do a low level emulation of the cpu. How else are you going to run SNES binaries on the GBA?

As for asking the authors of the emulator if they're going to able to get full speed. Of course they think they will. I've followed the progress of a lot of emus on the DC scene and everyone thinks they're going to be able to make it work at the end of the day. You know what - 99% of the time they don't manage it, and most of the time the reason is that no matter what you do the hardware is just not capable of emulation, and emu authors refuse to accept this.

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Wow, my simple little post has caused quite the uproar.

I have to say I'm with Halo here; atleast somebody thinks that the-glass-is-half-full. It's a work in progress here folks, lets cut the guys some slack.

ok, 20 quid says it will never run all games with full sound, mode7, transparency and windowing at full speed.

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ok, 20 quid says it will never run all games with full sound, mode7, transparency and windowing at full speed.

Well, duh.

Show me any emulator that does every game with all the bells and whistles, and I'll be impressed.

No bet, I'm afraid.

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Ive tried 2 snes smu's on the GBA and both are pants.

That's interesting, because this is the first SNES emu for the GBA.

I've been using this emu since it was first released and can tell you that it already plays the likes of R-Type, R-Type III and Axelay perfectly.

There is a huge scene for adding speed hacks for the emu (check out the forums on www.snesadvance.org) and it's getting better all the time. I'm absolutely dumb-founded as to how people who haven't even taken the time to check the emu out are blasting it.

It can't run Chrono Trigger?! :( It was only released about a month ago!

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I'm absolutely dumb-founded as to how people who haven't even taken the time to check the emu out are blasting it.

Because we're all cynical fucks here. You'll figure that out once you have a few more posts under your belt. :(

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Hi. There is a reasonable gp32 snes emulator.

It's barely capable but is playable and to get a decent framerate (frameskip 2-4) sound is definately a no-no. As far as I can tell, it's a port of snes9x with a dedicated ARM core, which means is probably as good as it's going to get.

This is on a gp32 running at 133mhz+ (and it has 8 megs of ram to store the rom in.)

the gba runs at the terrifying speed of 16.78mhz.

So yeah, good luck if you want playable snes roms on your gba.

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So yeah, good luck if you want playable snes roms on your gba.

Here's an idea: try the emulator! I almost completed Aladdin on the way to work today, and can honestly say the game was 100% playable speed wise. There are some issues in regards to some minor graphics glitches here and there, but overall it’s great.

Look, this thing isn’t perfect. It can not run that many games, it runs even fewer at playable speeds, but to just dismiss it so off-hand is just not right.

Because we're all cynical fucks here. You'll figure that out once you have a few more posts under your belt.  :(

I've been lurking here for a while, so I’m quite used to the cynicism of some posters.

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Here's an idea: try the emulator! I almost completed Aladdin on the way to work today, and can honestly say the game was 100% playable speed wise. There are some issues in regards to some minor graphics glitches here and there, but overall it’s great.

Look, this thing isn’t perfect. It can not run that many games, it runs even fewer at playable speeds, but to just dismiss it so off-hand is just not right.

I've been lurking here for a while, so I’m quite used to the cynicism of some posters.

Sadly, getting people to actually try something before they condemn it is a next to impossible task.

The cynicism on this forum does seem to be getting worse.

But atleast it seems that a few people appreciate my posts. :P

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The DC isn't exactly designed to be a 2D platform afterall therefore the rotation of sprites etc has to be handled by the CPU.

im not do sure if your right about that, but you could be. Its just that ive heard it said that the dc has great 2d capabilities compared to the ps1 etc

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im not do sure if your right about that, but you could be. Its just that ive heard it said that the dc has great 2d capabilities compared to the ps1 etc

Compared to the PSone yes, but the PSone was all about the 3d. (Where as the Saturn was a 2d powerhouse.)

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