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Дата изменения: Fri Feb 4 20:38:59 2005
Дата индексирования: Mon Oct 1 20:04:02 2012
Кодировка:

Operating system driver

All communication between a computer and DSP board are going trough input-output ports of ISA bus. Access to these ports in Windows NT operating systems family is allowed only for drivers, that work on the operating system's core level. So, the driver is needed to escape this limitation. Besides, data buffer in the DSP board become full with rather high speed during scanning, and these data need to be taken with some period. In other case information will be lost. Programs that run on the user level of operating system depend much upon the systems resources, number of programs running, and due to this they cannot provide speed and synchronization level that is needed to communicate with input/output ports.

When the data stored it the DSP board are ready to transfer, it generate an interruption. Responding to this interruption driver reads data from the board and transfer it to a server for further processing. Different interruption processing scenarios are possible depending on scanning regime. Obtained data are filtered in special way to exclude unnecessary information. It allows to reduce processor usage.