gpib speed

[michaelg]

The GPIB spec says the communication occurs up to 1 megabytes/sec. The NI PCI-GPIB card only seems to transmit at 12.5 kilobytes/sec.

Is this rate fixed or can the card transmit and receive at 1 megabytes/sec?

Thanks,
Michael

[Kim L]

Michael,
The NI PCI-GPIB board can transmit up to 1.5 Mbytes/s using IEEE 488.1 handshaking and 7.7 Mbytes/s using HS488. There is some overhead caused by the handshaking. Transfer rates are higher when transfer size is higher. See page 752 of the 2001 catalog for a chart of this relationship. For instance, the transfer rate is roughly 600 kbytes/s when transferring 400 bytes. The rate goes up to over 7 Mbytes/s when transferring 25 kbytes.

For more information on using HS488, see page 7-2 of the NI 488.2 User Manual for Windows (see link below).
http://digital.ni.com/manuals.nsf/web_productcurrent/51275DF3EAF12D8B8625693C0061CD15?OpenDocument

Thanks,
Kim L.
Applications Engineer
National Instruments