What does the buffer consist of?

[JohnLabview]

Dear all,

I am a beginner on Labview. I am trying to write my first .vi to sweep I-V curve using Keithley 2450.

I have some confusions about how to read the buffer of 2450 after the measurement finishing.

My question is： What does the buffer consist of?  For example, if  I source Voltage and measure the current, then there might be both voltage value and current value at least in the buffer. So, how can I separate the different values when I excute read buffer SCPI commands? 

I have consulted the reference mannual provided by Keithley. It uses  TRAC:DATA? 1, 21, "defbuffer1", SOUR, READ. But I am still confusing about the exact buffer formates. 

Thanks for any reply.

Sincerely,

John

[crossrulz]

I recommend you just use the LabVIEW driver for your instrument.  There is a Fetch function which does it all for you.