Difference between revisions of "DMA Mode"

Revision as of 18:37, 16 July 2010

DMA Mode

DMA stands for Direct Memory Access, it is a way of allowing a device to directly access memory blocks without the involvment of the Central Processor Unit. This reduces the processing overhead and in the case of the Acekard, reduces lag associated with MicroSD data transfers.

Games are loaded using Yellow DMA mode by default, which enhances performance in many games. There is no way to turn off DMA, it is on permantly. AKAIO has 3 different DMA modes which should between them work for all games. For this reason, non-DMA mode has been removed as it is no longer needed. You can tell which DMA mode is being used from the colour of 'Loading'; Yellow is the newly added DMA mode, Green is the previous QuickSave DMA mode and Red is the original DMA mode.

As of v1.7 the new DMA yellow mode has been made default, this mode is significantly faster than the other two DMA modes. Loader encryption was added starting with AKAIO 1.6RC1 due people such as those behind the edge-i (a fake cart which is being passed off as an i-edge) ripping off AKAIO and passing if off as their own work, as well the decrypting and releasing antics by certain tosser. This added encryption increased loading times, Yellow DMA mode restores loading times to those of AKAIO 1.5.1 while at the time is still encypted.

AKAIO has a database from which it determines which DMA mode is best to use with each game. If you are having issues with a game or you are using game which has been released since the last update, You can override which DMA mode AKAIO uses by holding down (A) or (X) after you launch the game. (A) will force AKAIO to use Original DMA mode, (X) will force AKAIO to use QuickSave DMA mode.

There is no way for users to force the execution of a specific DMA mode either globally or on a per-ROM basis. DMA-Yellow will normally be used unless the user inturrupts its execution by pressing one of the above mentioned buttons. However, some problem ROMs have been preset through the loaders to access a particular DMA mode. This behavior is normal and can not be overridden. There is currently no collected list of the ROMs which have a pre-set DMA mode.

For games that are problematic with DMA mode, please make sure to first update the loaders to the most recent version. Updated loaders can be found at the Loaders Download Page or via Wi-Fi Update from within AKAIO. If you notice a problem even with the latest loaders, please visit the AKAIO ROM Compatibility Page. Add your problematic game as needed by following the on-site instructions. You may also need to visit the AKAIO forums to add a bug report, please read the rules and previous bug reports before submitting your own.