Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
compatibility of ppsspp ?.
04-13-2021, 12:11 AM
Post: #2
RE: compatibility of ppsspp ?.
Quote:Will there be any chance that ppsspp for BB OS 7/nokia asha (j2me midp 2.0)/3ds/ps vita would appear?

We used to have support for old Blackberry and Nokia devices. It was slow but some games worked. Support in latest versions has been removed, because supporting those platforms was making it increasingly hard to improve performance and functionality for newer devices.

The PSP has 64 MB of RAM, 2 MB of VRAM, and a single core 333 Mhz CPU.
The 3DS has 128 MB of RAM, 6 MB of VRAM, and a dual core 268 Mhz CPU.
The Vita has 512 MB of RAM, 128 MB of VRAM, and a quad core 444 Mhz CPU.

It's tempting to try to multiply the core count by Mhz, but that's not "real". You can't emulate a single core CPU using 4 cores simultaneously, because CPUs simply don't work that way. Effectively, that means trying to emulate the overhead of emulation with 80% the power (3DS) or 133% the power (Vita.) Neither one is enough. 1000 Mhz is probably the minimum for a playable experience. This fits the general rule of needing a 3x more powerful device to emulate.

But let's assume you just want to watch a slide show of a PSP game and are fine with really poor performance. The next problem is RAM. Again, naively, the PSP RAM size "fits" inside the others, but that's not considering the overhead of emulation (which is significant.) We also have features like save states (I assume you probably want those) and everything takes memory. In the end, only the Vita has potentially enough memory - and it'd be tight. It might randomly crash when trying to save state.

There's another problem though, and that's the GPU. I didn't list them because they're not as directly comparable. The PSP GPU is a bit hard to implement, especially because it works differently than other GPUs.

See here for some disappointment from someone did work to port PPSSPP to a more powerful device than either the Vita (maybe arguable on the GPU, but definitely a faster CPU) or 3DS:
https://github.com/hrydgard/ppsspp/issue...-816799553

Sony just included PSP hardware inside the Vita to accomplish running PSP games on it. And that doesn't even run all games perfectly.

Quote:Is ppsspp currently supporting or planning to support android device that uses x86 cpu like razr i or mips cpu like ainol novo 7 paladin?

It should build fine and run. I think people have tested it on some x86 devices. It also compiles now on MIPS, although that might require a bit more work.

That said, MIPS devices especially tend to suffer from the GPU problem. See the link above, it was about a MIPS device. The GPU is just too slow. And no, the GPU architecture won't be similar to the PSP's. That's really the biggest problem.

So the reasons these things haven't happened? It's not a trivial amount of work, the best case is mediocre speed, and the vast majority of interested people have access to at least one device more suitable for PSP emulation.

That said, I have heard of efforts for a hybrid solution on the Vita: leveraging the hardware of the PSP, but also taking significant inspiration from parts of PPSSPP. I don't know the current status or if it worked out.

-[Unknown]
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
compatibility of ppsspp ?. - jackyjoy123 - 04-12-2021, 02:01 PM
RE: compatibility of ppsspp ?. - [Unknown] - 04-13-2021 12:11 AM
RE: compatibility of ppsspp ?. - Zinx777 - 04-14-2021, 12:02 PM
RE: compatibility of ppsspp ?. - [Unknown] - 04-15-2021, 01:12 AM

Forum Jump: