C Andrea

Check your firmware level against what is available for it (1.7.14 now).

I wonder what commands are in use.  If doing a fast trigger model operation, I can envision that front panel processing might slow down.
How do you resolve the freezing?

The DMM6500 can receive ASCII commands on the LAN.  The PLC needs a raw socket connection on port 5025.

Check out the User Manual on Trigger Link.
Also section on stepping and scanning for an idea of how to handshake with external current source.

When running this Lua code on the 2636B, the only file system available is the USB drive on front panel.  You need to insert a FAT32 formatted USB drive into the port.

I think instead you are wanting to put the information to the HDD of the computer, right?

In your document, it looks like two different tests were defined.
The 2604B contains two SMU.  You just need some sweeps.

Take a look at KickStart IVC if you don’t want to write code.
Or get our free Test Script Builder or TSP Toolkit.
There are samples with TSB.
Test Script Builder
With these you can execute sweeps and copy/paste data to Excel.
 

An update:  with version 1.13 of Clarius software for the 4200A-SCS, there are now KXCI commands for error retrieval and error clear.

Visit tek.com and download and apply updated Clarius for 4200A-SCS.

:ERROR:LAST:CLEAR

:ERROR:LAST:GET

The printbuffer() can take multiple buffer elements:
printbuffer(index1, index2, defbuffer1.readings, defbuffer1.relativetimestamps)

This well result in comma delimited reading, time, reading, time, etc according to the index values.
The receiving code will need to parse it.

If the ohms of the sample are very large, the RC time constants can be surprisingly long.  Minutes or hours is not out of question.

In these cases, it might be sufficient to define a procedure where you take the measurement after XX time of electrification.  Such a consistent method would allow comparison of sample A to sample B, etc.

Unrelated:  you may want to consider some shielding for the setup.  With connections in open air, results are susceptible to EMI and charged particles from air.  Simply walking past the setup can be reflected on the picoammeter.

Low level measurements handbook

In the *idn? response, after the serial number is what we want.
Your unit has C01 firmware.  You are at the latest for your unit.
Only units using a Bxx level are compatible with the B04 version from Tek.com.

Check out the sample posted on our github for the DMM7510.
The code for control of digitizer will be essentially same for DMM7510 and DMM6500.
Sample Code - look at DigitizeV samples

Just the spec of the A/D on the DMM7510 is better:
18-bit vs. 16-bit
hardware comparator-based triggers vs. firmware detect
able to AC couple to the signal