Contec GP-IB(CB)F, Руководство пользователя

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4. Functions
GP-IB(CB)F, GP-IB(CB)FL
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4. Functions
This section describes the functions of the PC card.
Bus Master Function
Bus Master Transfer
The bus master data transfer function uses time when the PCI bus is idle to perform direct DMA transfer
of data between the PC card and the application memory space. The application memory space means a
static area defined using a normal variable declaration. Under Windows, the application memory space
is represented using logical addresses and does not necessarily map on to a continuous physical address
space. However, the PC card is able to transfer data consecutively to the discontinuous physical address
space. Bus master data transfer can be performed for a maximum 64MBytes physical memory area. The
actual memory size able to be used when setting up a data transfer in an application depends on the OS
type and the size of memory in the PC.