MKS PR4000B "S-model" - communication protocol

[Blokk]

Dear LabVIEW programmers,

A friend asked me to help him to setup RS232 communication with an MKS PR4000B single channel pressure sensor controller. The problem is that, recently I have very limited time, I do not have access to the device, and testing through phone is a bit slow 🙂 I have found some old discussion threads about this model, but it did not really help much so far. Well, my capabilities are very limited lets say 😉

Therefore I ask for some help: has anyone dealt with this MKS model in the past? I used a lot the "F" dual channel subversion, which has a very simple RS232 comm protocol, and easy to use. However, this S-model protocol confuses me. We already tried different commands to send to the device, and no success so far (like using the "!" 0x21 command in different combinations). We used MAX to test the comm, and the settings are correct, the device replies with "\r", meaning could not parse our sent commands. I have attached the manual in pdf, the relevant part comes from page 45.

The required action is very simple: we just need to read out the single pressure transducer readings in a loop.

Thanks for any help or hints! 🙂

[Blokk · Accepted solution]

Ok, after some more search in the forum, I have found the solution:

https://forums.ni.com/t5/LabVIEW/Command-syntax-for-PR4000B/m-p/1818401/highlight/true#M624343

We need to send a "%1" command first, to activate ASCII mode. An undocumented feature, pfff 😄

What is strange that, using NI MAX we still cannot make it work via the VISA Test panel (all settings are ok, term char set to CR). However, PuTTY worked, typing in "%1" then Enter, then "$" and Enter nicely displayed the measured pressure value. Lost some time due to MAX (i helped friend via phone/chat), next time I start testing with only using PuTTY.

Tomorrow a LV VI will be tested, if it works, I will mark this post as solution (solution from the above link).

[David2733]

Hello Blokk 

Can I get a copy for your set up? 

I am trying to setup PR4000B"S2V2" to measure the pressure transducer. 

However, I lack of experience on the LabView and trying to learn some progress for this. 

But I cannot find this machine on the LabView setup... 

It will be very helpful if I can get a copy of this.

Regards

[Blokk]

Hello!

Sorry, I do not have that project anymore. But I suggest you to start learning LabVIEW using the available sources. If you need help, it is more likely you get any if you show some effort. So when you post a question regarding to your code/VIs, always provide the VIs/project itself and explain what is your goal, what you have tried so far, what error you see, etc.

In this way you will learn on the way, and also get relevant help. 
It is recommended you start a new post thread dedicated to your specific questions, and not continuing this old thread.

Here you can learn the communication protocol:
https://www.mks.com/f/pr4000b-digital-power-supply

Good luck!