Pci Sound Card Wdm Driver For Research And Design

Windows 2000 PCI audio card WDM driver's architecture and developmenttechnology are analyzed completely. The key processes in driver development arediscussed in detail. Adopting the general-to-special research method, based on thesample AC97 miniport driver contained in the DDK and the special features of theaudio card, this paper introduces how to develop a driver for a given audio card.The design philosophy and overall architecture of Windows 2000 are presentedfirstly. The concept of interrupt priorities, the structure of I/O request packet and I/Oprocessing sequence are specially discussed. Then the characteristic and the layeredarchitecture of Windows Driver Model are analyzed. The two important basic datastructures DriverObject and DeviceObject, the key routine DriverEntry andAddDevice and the driver's load sequence are specially expatiated. It is a fact of lifethat device drivers must interact with "real" hardware, so hardware basics includingaccessing device registers, DMA mechanisms and PCI bus architecture are alsointroduced. In addition the paper discusses the architecture of the audio card and thebasic audio concept. The developed object of the paper—Banjo audio card is analyzedin detail including the architecture, the work mechanism, the function of the mainmodules and the usage of the function registers. To support multimedia devices suchas sound cards, Microsoft supplies multimedia driver architecture which is mentionedin the paper. The Microsoft DDK contains a sample AC97 miniport driver whichprovides a framework for all PCI audio card driver development. Studying the sampleAC97 driver in detail, analyzing the framework and the main class objects of thedriver are extremely important for PCI audio card driver development. Based on thesample driver and the special features of the Banjo audio card, the driver is developedin function module one by one. The driver's load/unload process, the basicplayback/record functionality implement and the ISR routine and the DPC routineimplement are respectively elaborated on. At last the usage of the build tool, the driverinstallation and how to set up a build and debug environment are specially introduced.The involved knowledges in PCI audio card driver development are expoundedin this paper. Not only PCI audio card driver but also various types of Windows 2000device driver can borrow ideas from this paper.