National Instruments 653X - Manual (Page 116)

© National Instruments Corporation E-1 653X User Manual
E
Optimizing Your Transfer Rates
Use this appendix to determine the maximum transfer rate for your device,
optimize transfer rates, and to see example benchmark results.
Determining the Maximum Transfer Rates
The maximum sustainable transfer rate a 653X device can achieve depends
on the minimum available bus bandwidth and is based on your computer
system. The maximum sustainable transfer rate also depends on the number
of other devices generating bus cycles, your operating system, and your
application software. The maximum sustainable transfer rate is always
lower than the peak transfer rate.
The average bus bandwidth from highest to lowest is in the following order:
• PCI/PXI-6534
• PCI/PXI-6533
• AT-DIO-32HS
• DAQCard-6533 for PCMCIA
With the 6534 devices, if the data you are acquiring/generating fits in the
onboard memory, the transfer rate is not limited by the bus bandwidth,
only by the maximum transfer rate based on the protocol used. These rates
are listed in Table E-1. The peak transfer rates are based on using a
1 meter cable.
Table E-1. Peak Transfer Rates Based on Mode and Protocol Used
Mode/Protocol Peak Rate (MS/s)
Handshaking 8255 5
Handshaking Level-ACK 3.33
Handshaking Leading-Edge Pulse 3.33
Handshaking Long Pulse 3.33