New Vba2a-r Pretty Good


Wow guys, I was asking a *technical* question, or if you prefer, on a *technical* tone. I just don't understand the technical difficulties that can exist emulating an ARM architecture on an ARM one...
 
It's not that simple. The GBA uses an ARM7 and the GP2x uses an ARM9, first of all-- they are from the same architecture but not the same generation and are far from identical designs. Secondly, you cannot natively run code like that even on the same architecture as it would require 100% direct hardware-level access, as in "No OS" in all likelihood, to function-- there would need to be a working interpeter to translate the ARM7 code to something the ARM9 will understand, and there may be instructions in use that don't even exist on the ARM9.

Additionally, the GBA is NOT just an ARM7-- it also has a custom 2D processor that handles all graphical work, as well as niceties like hardware-accelerated scaling and rotation.

Simply put, you can't just drag-and-drop an ARM7 program onto an ARM9 system and expect it to run at 100% just like that. Also note, GBA emulation is very slow on the PC side of things as well-- the system is much newer than the PSX-- there are nowhere near as many emulators for it, the science of emulating the system is far from perfect. Very far.

In short, have patience.
 
Of course, this is not to mention that this is an emulator designed for x86 in particular, not the GP2x. Hell, it's probably written in C with no ASM core for the ARM7 emulation, which will make it astonishingly slow on anything but an 'overkill' processor-- hell, running VisualBoyAdvance's Win32 build I never saw 100% performance with sound and 0 Frameskip on any less than a 700 MHz Celeron (not a beefy CPU, but compared to the ARM7 used in the GBA, a veritable powerhouse.)

There are arcade emulators like Nebula for Model 2 that are emulating systems with CPUs made a decade ago that don't run full speed. Hell, I was running Gunblade NY on my Athlon 64 X2 machine (a CPU with 2 2.2 GHz cores, overclocked to 2.8 GHz.. only one engaged for the emulator naturally) and it ran at about 1/2 proper framerate. The game's native hardware has an i960KB at 25 MHz, a 68000 @ 12 MHz and a couple of sound processors. I repeat, it didn't run full-speed on a *2800 MHz* Athlon 64.

See what I mean?
 
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