How to use full 16MB RAM on DSi and DSi XL

support for the ARM toolchain
Post Reply
laser
Posts: 17
Joined: Sat Aug 14, 2010 5:49 am

How to use full 16MB RAM on DSi and DSi XL

Post by laser » Tue Aug 24, 2010 10:48 am

Hi All,

I have a question....

I understand the DSi and DSi XL have 16MB of RAM compared to the DS lite which has 4MB RAM.

Is there a way to set the memory size when building so I can use this extra RAM?

Many thanks,

laser

WinterMute
Site Admin
Posts: 1986
Joined: Tue Aug 09, 2005 3:21 am
Location: UK
Contact:

Re: How to use full 16MB RAM on DSi and DSi XL

Post by WinterMute » Tue Aug 24, 2010 11:01 am

Currently you can't run homebrew in DSi mode but, when you can, no build setting is necessary, I've set things up to be automatically hybrid.
Help keep devkitPro toolchains free, Donate today

Personal Blog

laser
Posts: 17
Joined: Sat Aug 14, 2010 5:49 am

Re: How to use full 16MB RAM on DSi and DSi XL

Post by laser » Tue Aug 24, 2010 11:04 am

okay, thank you WinterMute. I'll keep an eye out for that release.

Many thanks,

laser

laser
Posts: 17
Joined: Sat Aug 14, 2010 5:49 am

Re: How to use full 16MB RAM on DSi and DSi XL

Post by laser » Thu Aug 26, 2010 9:55 am

Hi WinterMute,

I saw the DSlink release - many thanks. I needed to read it several times to understand. I thought is was a simple case of setting the memory size at the time of the build but obviously there is some hardware restricting access to the extra memory unless you are in this "DSi mode". Is there a write up somewhere explaining the "DSi mode"? I would like to understand the problem and try to help find a solution.

I have a DSi XL so probably can't use this hack to enter "DSi mode" anyway, but the DSlink program is great for testing non fatlib programs - one less reset needed now - many thanks

laser

WinterMute
Site Admin
Posts: 1986
Joined: Tue Aug 09, 2005 3:21 am
Location: UK
Contact:

Re: How to use full 16MB RAM on DSi and DSi XL

Post by WinterMute » Thu Aug 26, 2010 11:59 am

It's fairly simple, if you're in DS mode there's only 4meg, you need to be in DSi mode to get 16meg. There's nothing you need to do, all homebrew compiled with recent devkitARM/libnds will have access to that 16meg via malloc. For devkitARM r32 I'll probably be adding a spec file that will allow you to use more than 4meg for code/data etc but, if I'm honest, I'd really prefer to find a method to stick with a hybrid approach where homebrew works on DS whether or not it uses DSi features.
Help keep devkitPro toolchains free, Donate today

Personal Blog

Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests