A Little Confused About The Gp2x


Cyclops

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I'm being stupid. I know and maybe I don't get it.

the GP2X has linux/SDL and some fancy 2D thing that can do scaling.

How close in real terms is that to literaly downloading, compiling running a program on the GP2X.

endianess, memory issues, screen size... just 3 possible issues.

to create impressive games, etc on any system with less than 1ghz of cpu power - you need to hit the hardware directly

you can render the screen at 320x240, which of course you can. The question is whether it looks crap when you do it

check how much CPU even the smallest SDL app eats

most emulators on the gp2x won't be using linux
 
I didn't know that the GP2X OS would include SDL in it. Even if it does, it won't be simple recompiling, but it won't be obscenely difficult either.
 
You can create a crosscompiler env at your linux box at home. And then cross compile for the gp2x. The machine is running linux. And i bet, there is no X server on it, only a framebuffer, and the easyest way to port something to it, would be using sdl. 80% of all linux emulators support sdl.
There is only one problem. The crosscompiler will only support ONE cpu at compiling time. So that your emulator is only running on the main cpu. If you want to use the second CPU in your gp2x, you need (a lot more) modification to the source. So default and at the beginning, most gp2x applications will only support ONE cpu of the machine, until the devvers find out how to use the second one. I bet to 99% that the linux kernel, will not default support the second cpu. couse their core is not the same, so it is not possible to use a smp kernel, and let the OS do all the hard things for us.

Or in easy words. Easy cross compiling emulators will not run faster on the gp2x, than on the gp32. (okay, 33Mhz faster )

cu
 
common mistake there - everyone seems to assume GP32 runs at 166, where it's normal speed is closer to 133Mhz, like Jarska333 points out :) An important difference when comparing the GP32 & GP2X, as we don't know what the GP2X will be overclockable to.
 
Squidge posted on Sep 9 2005 at 04:12 PM said:
common mistake there - everyone seems to assume GP32 runs at 166, where it's normal speed is closer to 133Mhz, like Jarska333 points out :) An important difference when comparing the GP32 & GP2X, as we don't know what the GP2X will be overclockable to.

individually the cores are rated up to 250mhz according to the ARM site but they may go beyond that or they may not even manage that due to communication issues between the two cores. Overclocking is pretty unpredictable, it's gonna be a case of wait and see.
 
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my gp32 oc's to 220mhz stabily, and osnes9x still runs like crap when frameskip is low and sound is on. Let's hope that this is more to do with the lack of development on that piece of software rather than that kind of clockspeed being insufficient for snes emulation.
 
There isn't much difference between 150 and 192 in SNES emulation... Atleast in my machine. Some problems just aren't fixable by just adding more Mhz. Coding is required... :)
 
Don't forget the memory in the GP32 is relatively slow. The memory was designed to run with a 66 MHz CPU and that memory doesn't overclock so there is a speed bottleneck there. The memory in the GP2X was designed to work with a CPU running at 200 MHZ. So a GP2X will run faster than a GP32 both running at 200 MHz because of memory speed. That will make a big difference, not even including the second CPU. With that who knows how much you can squeeze out.
 
Jarska333 posted on Sep 10 2005 at 12:25 AM said:
Who are you, and what have you done to DaveC? :blink:
Give the guy some credit for not being like a broken record. :) He simply says what he thinks, whether it's something good or something bad. Just because he sometimes "dares" to say something negative doesn't make him a pessimist overall.

BTW, DaveC, are you a dev? I'm just wondering how you know all of this stuff...
 
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nah, he's not a dev(right?), but a knowledgeable guy. aren't we all ;)
 
No I am not a dev. I can't code a byte (been known to push a pixel or two though). If I could you all would have perfect SNES and MAME with perfect sound on all games because I am so picky.

I have just been in the "scene" for awhile, shows my olde age. I was playin' Asteroids in the arcade when most of you younguns' weren't even a twinkle in your mother's eye yet :p
 
DaveC posted on Sep 9 2005 at 11:17 PM said:
Don't forget the memory in the GP32 is relatively slow. The memory was designed to run with a 66 MHz CPU and that memory doesn't overclock so there is a speed bottleneck there.
Almost, but not quite. The memory in the gp32 can be set to run either at the cpu speed or at half the cpu speed, and it's quite happy up to 66mhz (which is why 132mhz cpu is always stable). Pushing the memory over 66mhz is overclocking, which is why pushing the cpu to 133mhz or higher is overclocking.
 
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You don't have to be a software dev to have a good understanding of hardware. Remember, a lot of people build and/or service PC's who have no programming background. But one often gives at a little insight into the other.

Being old kinda helps as well. Like DaveC, I was also around since the early days and still clearly recall when Pong and Space Invaders showed up. Even magazines back then were really different - computer and gaming magazines often had programming tutorials and computer hobbyist articles. That's how I ended up learning BASIC and gained an understanding of hardware and software, even though I didn't go into the computer industry. Today's popular magazines by comparison are crap, I feel bad for kids in that respect, because the ONLY thing magazines do now is try to sell them more games. There's hardly ever any effort made to explain how hardware or software works, and never a programming tutorial.
 
I wish I was born in in the same age. Time when gaming rised, the magazines where more interesting and not as commercial as now, the experience of every new genre beginning, etc...
Beginning as programmer would've been quite easier then than now, I believe.

When releasing a game, there was mostly 1 creator, who did everything, now you have teams larger than 200 people.

And when you want to become a programmer, you'll probably have to start with C++, and for commercial games, I wonder if there's any posibility of stepping in the gaming industry. Isn't it too overwhelming to step in as newbie, while all the giants started developing for the nes, or even earlier...

The only magazine I buy once in a while is Retro Gamer. :p (too bad it's so friggin expensive, especially when getting a subscription.)

I'm probably not taken very seriously because I'm a newbie on these forums, and I don't even own a gp32. (Getting the gp2x.)
But ah well, back to my Sams teach yourself C++ in 21 days. ;)
 
Draken posted on Sep 10 2005 at 07:26 PM said:
But ah well, back to my Sams teach yourself C++ in 21 days. ;)

don't give up ;) do you plan to create something for the gp2x?
 
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