I am using a Keithley 6517A to measure charge (Coulombs) via an IEEE 488 connection to LabView. Before a measurement can be taken, however, I need to zero-check (Z-Check, Zch) the instrument and set the relative (REL, Key 30) as soon as the first reading is displayed. If the instrument is still measuring the initial zero-value to which all other values are taken relative to, activating REL will return an error. So I need to send the commands:
: Syst : Zch OFF;
: Syst : Key 30 (without spaces, this dumb setup turns the script into emoticons)
Where the second command (: Syst : Key 30) is not activated until the instrument has measured it's first reading. In other words, I need to continuously query the divce to tell me when the instrument has made it's first reading, then turn on the REL. Any advice on the matter is greatly appreciated! I have attached the Keithley 6517 vi's for reference.