Hacking R4 hardware specification

[eltia]

Hi all,

I am wondering if there is a hardware specification of R4 that I can look at? In particular, I am interested to know the size of the internal memory of R4.

Recently, I read from a Japanese magazine that Archaic Sealed Heat will be the first DS title to use 2Gb ROM. (And consequentially, more titles would probably use ROM size that is greater than 1Gb. e.g. Dragon Quest IX.)


I am curious will there is a possibility that R4 be able to run large ROM? A related query is, has the R4 development team begun to look at this possibility? Thanks in advance!

 

[xcalibur]

Of course, the 2gb roms are gigabits, that means 256 mb and R4 has expandable memory up to 2 or 4 gigs.

The size of the rom doesnt matter, only the speed of the memory card

 

[Rayder]

The R4 uses a microSD as its storage medium, it has no "internal" memory per se. It can store up to 2GB (that's gigabytes...capital "B') depending on the microSD you put in it. ASH will be 2Gb (that's 2 gigabits....lower-case "b", which is actually only 256megs). A 2gig microSD should be able to hold about 8 games that size. 1 gigabyte = 8 gigabits.

Their is a new standard for SD cards; SDHC (Secure Digital High Capacity). The R4 does not support the SDHC microSD's, which can hold much more data, but that really isn't a problem at this point other than limiting how many huge games you can put on the card at once. Non-SDHC microSD's only go to 2GB (gigabytes). I've heard of some non-SDHC microSD's that go 4gigs, but I've never seen them myself and if you do find one, it could be hit-or-miss as to if it will work because it is outside of the non-SDHC standards, which stops at 2GB.

As long as the game doesn't use extreme streaming technology like Castlevania: Portrait of Ruin (which requires a very fast microSD to play without crashing) or tech like Tony hawk uses (runs slow on most flashcarts), it should play ASH just fine.

If you want a card that DOES support the SDHC microSD's, get the CycloDS Evolution. Its limit is only as big as the SDHC microSD's can get, which is to say, much larger than the what the R4 is capable of. I believe the technical limit on SDHC SD's is 32 gigabytes. That's 256 gigabits.

Hope that makes sense to ya and answers your questions.

 

[eltia]

Thanks! I was thinking there maybe internal memory inside R4 itself that acts as temporary memory, and these memory could become barrier for loading ROM that is larger than 1Gb.

So when a ROM file loads for the first time from micro SD, does it get loaded onto DS memory directly? Or is there a temporary buffer on R4 to speed things up?

 

[chuckstudios]

It loads the ARM7 and ARM9 binaries into RAM, then accesses the NitroFS for game resources directly from the microSD card during game execution.

 

[eltia]

That's good to hear. As long as R4 doesn't have any intermediate memory in-between, chances are good larger ROM size should work with it. Thanks again!