my GPIB is reading slow

[AxE]

any way to increase the GPIB write and read speed?
it take about 0.7-1sec to finish reading 101000 bytes

[AxE]

btw reducing the commands to write and data recieve
but there should be more ways to increase the speed

[Dennis_Knutson]

What type of GPIB board are you using? What's the instrument? Is there a binary transfer mode and are you using it?

If you are using a fast GPIB card and the most effecient data transfer, there might be nothing you can do. The theoretical max transfer rate for GPIB is 1.5 Mb/s but in the real world, rates rarely approach this. Many instruments (especially older ones), were never designed for high speed transfers. There could be a lot of other things going on. The instrument receives a read command so it first has to transfer the data to it's write buffer and that's going to take some ammount of time even before you can start your read. You might want to check the instrument manual or contact one of their application engineers to determine the instrum
ent's specification to and see if the rate you're seeing is expected.

[AxE]

National Instruments GPIB Interfaces(PCI-GPIB) is the card I using,

The instrument is TDS 420A, there is a binary transfer mode, and i am using

I hope i can recieve real time data from it, but I tested alot of ways and have some conclusion,

it can display waveform but only screen by screen
(what we see in oscilloscope, that mean it is not a real time waveform)

It will discard and refresh the oscilloscope screen after every send request, no matter how long is the length i requested it to send

[Dennis_Knutson]

I truly think that the instrument is the limiting factor here. Real time GPIB is kind of an oxymoron anyway, especially with waveform transfers. A different model scope might have a faster transfer rate but you're never going to see "real-time" because some finite amount of latency is inherent. For the faster transfer rates, go with a PCI or PXI scope card. And, since these don't have a separate display, what someone sees on the pc's monitor is "real-time".;)