rs 232 device data reading limits keithley 2400 IV with labwindows

[dsappet]

I had that initially but depending on forcing current or voltage i get one extra reading ... so i made it <= and added a condition that if p returns null to stop. It works great for small sample sizes I can take 100, 200, 1000, 1800, readings and be happy as a clam. I have found that the function usually times out if there is no data or something wrong (I messed up a few times lol) so why it hangs it unknown, I think I will try to run it on a different pc, i will find out how large the data packets are and what 2000 of them adds up to, I will also for the heck of it try playing with buffer size. Any other debug suggestions for now or to rule anything else out?

Thanks again for your help,

[JGS]

Hello,

I still think the number suspicious and suspect the buffers from rs232 as well as keithley.

I am not familiar with the Keithley 2400 but I am using the current meter model 2500.

From this model, I expect that the 2400 has a command to retrieve the actual number of available data: TRACE:POINTS:ACTUAL?. Maybe you can use this before retrieving the data.

As support for one of the other replies: which data format do you use e.g.

format ascii or ieee times number of elements / channels including terminators

i.e. number of bytes for each reading

Succes, Jos

P.S.

the smiley is part of the command syntax i.e. colon and capital P 

[dcl9000]

Hi! Douglas,

I have a Keithley 2400 Sourcemeter.  If you're willing to share your code,

let me try to run your code here and debug it for you at my site. 

Daniel

[dcl9000]

I just tried the CVI project (attached) that I created using the functions provided by Keithley.

(VISA dirver downloaded from: http://www.keithley.com/products/currentvoltage/?path=2400/Downloads#3,

file name: 24xx-850CV2.0.exe)

It says in the readme file that you need NI-VISA 2.5 or above.

There's no problem reading more than 2000 points (see the data output window image).

My CVI version is 6.0.  The instrument resource name is assigned by NI-MAX (4.3)

My settings of RS-232 port is the same as yours.

Hope this helps.

[dsappet]

dcl, I will hopefully have a chance to look into your code soon, I am attaching the program that I use, hopefully it is intuitive enough to operate. I have been working on another project that got prioritized over this but when I come back to it will look through your code and hopefully it will help, you'll find my project is loosly based off the rs232 example, I am running CVI 9.0 so you will have to recompile in your edition but I don't think there will be any other compatability issue's.

Thanks much for your help!

[ArashE]

Hello dcl9000. I just downloaded your source code, and unfortunately it doesn't include the files Ke24xx.h, Ke24xx.lib, Ke24xx.fp etc (The Ke24xx instrument drivers). Do you happen to have those by any chance? I would really appreciate your help! I only need to use the ke2420 to "Measure" voltages via GPIB in LabWindows CVI 2009

[rakinroll]

Hello everyone,

i am totally new to use Keithley 2400 via a computer. I want to take I-V datas from the device via RS232 port by using LabWindows but i dont know how i can do this. Please someone help me about how i use this program. Actually, i am so inexperienced with using ths program.

Thanks for your attention,

Teoman Özdal

Solar Cell Research Lab,

Mustafa Kemal University,

Hatay, Turkey

[Snowman 6008]

Teoman,

You can use the instrument driver that NI provides to communicate with the 2400 http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=1583 

Give the driver a shot and if you have problems, make a new forum post.

[rakinroll]

Snowman,

Is this driver suppotts RS232 connection? Because i do not have GPIB interface, i am trying to connect via RS232 port.

[Snowman 6008]

Teoman,

It does not, I would recommend looking at Keithley's website it looks like they have an IVI driver http://www.keithley.com/support/data?asset=16504 that should be able to be used over serial. If not, keithly should have a command set for the driver that can be used with VISA.