Operation theorem • 23, Figure 4.1.3 delay trigger – ADLINK PXI-2502 User Manual
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Operation Theorem
• 23
(NumChan _Counter=4, PSC_Counter=3)
Acquisition_in_progress
Scan_start
AD_conversion
Scan_in_progress
Acquired & stored data
(3 scans)
Operation start
Trigger
Delay until
Delay_Counter
reaches 0
Figure 4.1.3 Delay trigger
(NumChan _Counter=4, SC_Counter=2, retrig_no=3)
Acquisition_in_progress
Scan_start
AD_conversion
Scan_in_progress
Acquired & stored data
(6 scans)
Operation start
Trigger
Figure 4.1.4 Post trigger with retrigger
4.1.4.4 Bus-mastering DMA Data Transfer
Bus Mastering DMA Mode
In order to utilize the maximum PCI bandwidth, PCI bus-mastering DMA is
used for high speed DAQ boards. The bus-mastering capability of the PLX
PCI controller, takes over the PCI bus when it becomes the master. Bus
mastering reduces the required size of on-board memory as well as CPU
loading since data is directly transferred to the host PC’s memory without
CPU intervention.