Installing Extra Ram On The Gp2x

[God Ginrai]

I was wondering if it was possible, seeing as if you could install more RAM, then you could USE more RAM.

I know its not that easy, but I just want to know if it would even be a feasible task.

 

[Shikaku]

Not usably, it's already using the maximum possible without causing the motherboard to slow down.

 

[God Ginrai]

So you think any more would cause the motherboard to slow down? o_ô

 

[craigix]

What would you want more RAM for?

 

[God Ginrai]

The more ram you have, the larger files you can store in RAM, for emulation and such.

 

[reSpawn]

there was a link where a guy was presenting step by step how to add more ram on GP2X or GP32(I dont remember exactly)

 

[craigix]

The more ram you have, the larger files you can store in RAM, for emulation and such.

But why would you want the extra RAM? What are you planning to do with it?

 

[m8ex]

GP32 64MB Mod

 

[DaveC]

The more ram you have, the larger files you can store in RAM, for emulation and such.

But why would you want the extra RAM? What are you planning to do with it?

It would eliminate those annoying pauses/stutters in large NeoGeo ROMs

 

[Jarska333]

Of course, you'd need to persuade the authors of every emulator to ad support for the extra memory...

 

[Vimacs]

No you dont, thanks to the lovelyness of linux.
Extra ram would be nice for qtopia/gpe, i allready tend to need a swapfile evry now and then.
But afaik the mmsp2 cant handle more than 2*32mb

 

[DBH]

out of curiousity does any of the apps etc use the SD card as a space for swapfile data or is that way too slow? Still an option though somewhat no?

 

[Orkie]

out of curiousity does any of the apps etc use the SD card as a space for swapfile data or is that way too slow? Still an option though somewhat no?

GPE can, but it will wear out your card more quickly (not too much more quickly, but be aware that it will happen to some degree). It makes quite a bit of difference I'm told.

 

[Squidge]

Well, theoretically you could use SDR from 0x0 -> 0x1FFFFFFF, as the GP2X uses a shadow configuration. That's 512MB.

For correct operation, there would be a "memory hole" between 32mb and 64mb for the second processor, but considering Linux is running as the OS, there's no problem there, you could just split the memory up into several chunks via the MMU and makes it all seems like one contiguous chunk of RAM to applications.

Why you'd want to is another matter entirely, however...

(Hmmm, you could probably stick some SRAM @ 0x80000000 onwards too, once you've taken care about the NetChip that's living around there somewhere, but I'm sure 480MB should be enough for a handheld console...)

The only reason 32MB -> 64MB is slower to access than 0MB->32MB is because Linux automatically cleared the bufferable and cachable bits of the MMU table descriptors for locations outside it's memory range (don't forget it thinks there's only 32MB). I've manually altered the MMU tables, and can get full speed access to the whole 64MB. The emu I was playing with increased by about 3 fps too by doing so

 

[Aninhumer]

I seriously doubt it, but what about a memory mod for the second processor?
I don't know if it's possible, practical or even helpful, just an idea.

 

[God Ginrai]

Well, theoretically you could use SDR from 0x0 -> 0x1FFFFFFF, as the GP2X uses a shadow configuration. That's 512MB.

For correct operation, there would be a "memory hole" between 32mb and 64mb for the second processor, but considering Linux is running as the OS, there's no problem there, you could just split the memory up into several chunks via the MMU and makes it all seems like one contiguous chunk of RAM to applications.

Why you'd want to is another matter entirely, however...

(Hmmm, you could probably stick some SRAM @ 0x80000000 onwards too, once you've taken care about the NetChip that's living around there somewhere, but I'm sure 480MB should be enough for a handheld console...)

The only reason 32MB -> 64MB is slower to access than 0MB->32MB is because Linux automatically cleared the bufferable and cachable bits of the MMU table descriptors for locations outside it's memory range (don't forget it thinks there's only 32MB). I've manually altered the MMU tables, and can get full speed access to the whole 64MB. The emu I was playing with increased by about 3 fps too by doing so

Do you think you could pull off that much RAM?

 

[Epicenter]

Probably, yes. The iffy bit is you deviate from spec and therefore devs have to still program for units with 64mb only-- or they leave out users who didn't upgrade their RAM. It'd be a big pain-- soldering SMD ICs is hellish for most people-- so few would do it unless it was a professionally offered option at purchase time, a mail-away-to-get-it-upgraded deal etc. Only some apps would do anything too useful with it.

 

[God Ginrai]

Probably, yes. The iffy bit is you deviate from spec and therefore devs have to still program for units with 64mb only-- or they leave out users who didn't upgrade their RAM. It'd be a big pain-- soldering SMD ICs is hellish for most people-- so few would do it unless it was a professionally offered option at purchase time, a mail-away-to-get-it-upgraded deal etc. Only some apps would do anything too useful with it.

I understand what you're saying about compatibility, and that's what I think would be the biggest problems, but it would open some more doors if some developers accepted it.

 

[Orkie]

Probably, yes. The iffy bit is you deviate from spec and therefore devs have to still program for units with 64mb only-- or they leave out users who didn't upgrade their RAM. It'd be a big pain-- soldering SMD ICs is hellish for most people-- so few would do it unless it was a professionally offered option at purchase time, a mail-away-to-get-it-upgraded deal etc. Only some apps would do anything too useful with it.

I understand what you're saying about compatibility, and that's what I think would be the biggest problems, but it would open some more doors if some developers accepted it.

Some programs could take advantage of it with no modification. The PDA apps for example.

 

[Epicenter]

Probably all you need to do is find some larger-capacity RAM chips rated for 133 Mhz with the same pinout and you are basically set. It just won't be very easy to replace the old 32MB ones. May as well get RAM rated for 166 Mhz or higher to aid overclocking since 200 MHz CPU clock = 100 MHz RAM clock, 266 MHz CPU clock = 133 MHz RAM clock .. etc. Might help you break 300 Mhz easier.