Bimodal communications device driver.

摘要

A data processing system gives an application running on the operating system exclusive ownership of a hardware device. The system is operable in two modes. In the first mode the application interacts with the hardware device by making use of the processing system. In this mode many layers of the processing system are involved and the interaction time with the hardware is slow and inconsistent. In the second mode, exclusive ownership of the hardware device is granted to the application by the driver. In this mode the application has direct access to the hardware device thus avoiding the involvement of the processing system layers. The application accesses and uses the driver through a low latency processor interface linked into the application program itself. <IMAGE>