The Windows 2000 Device Driver Book: A Guide for Programmers (2nd Edition)

Without a doubt, drivers for DMA devices are more complicated than drivers for programmed I/O hardware. In return for this added complexity, the system achieves greater throughput by overlapping CPU activity with data transfers. The I/O Manager tries to simplify the process by providing a generic framework in which to perform DMA. This chapter has presented the details of the Windows 2000 abstract DMA model and discussed the various styles of DMA.

The next chapter begins the discussion of how devices report and log their operational status to the operating system.