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DMA Support

The KeyLargo IC provides DB-DMA (descriptor-based direct memory access) support for the following I/O channels:

• Ultra DMA/66 interface

• EIDE interface

• communication slot interface

• I² S channel to the sound subsystem

The DB DMA system provides a scatter-gather process based on memory-resident data structures that describe the data transfers. The DMA engine is enhanced to allow bursting of data files for improved performance.