JBUS and Python which way

[mjekl]

Hi,

I'm a newbie without a technical background making some technology
research for a company I work for.

My aim is to have an idea of the alternatives technologies for
accessing
information produced by a machine with a JBUS interface (RS232) and how
to
access this information realtime in Python (connecting a PC locally via
serial
port).

I'm aware of pyserial but I wonder if there is a library/module that
takes care of accessing/interpreting JBUS protocol. I've searched for
this without results.

I also searched the net looking for some information so that I could
have a
birds-eye-view on this subject and got the impression that a
possibility is to
have the communication (JBUS protocol / buffering) managed by some
hardware
component. Is this so? Can some-one give me some pointers/resources on
this
subject. Would it still be possible to work with Python.


Hope this makes any sense.
All help appretiatted.
Txs,
Miguel

 

[Oren Tirosh]

If you can't find any JBUS/Modbus modules specific for Python it's
possible to use one of the many C/C++ modules available and make a
Python wrapper for it with an interface generator like SWIG or SIP. You
say that you don't have much technical background so you may consider
hiring someone to do it. It's not a big project so it shouldn't be too
expensive.

Oren

 

[Alan Kennedy]

[mjekl]

> My aim is to have an idea of the alternatives technologies for
> accessing information produced by a machine with a JBUS interface
> (RS232) and how to access this information realtime in Python
> (connecting a PC locally via serial port).
>
> I'm aware of pyserial but I wonder if there is a library/module that
> takes care of accessing/interpreting JBUS protocol. I've searched for
> this without results.

A possibility you may not have considered is to use a Java library for
Modbus/JBus, and then use jython to control that. The following looks
like a likely candidate.

http://sourceforge.net/projects/jamod/

I imagine that writing your own cpython implementation wouldn't be that
difficult. I did some modbus work in C back in the 90s, and it was
pretty straightforward, but requiring a lot of finicky bit-twiddling.
I'm pretty certain that writing a python implementation would be a snap.

> I also searched the net looking for some information so that I could
> have a birds-eye-view on this subject and got the impression that a
> possibility is to have the communication (JBUS protocol / buffering)
> managed by some hardware component. Is this so? Can some-one give me
> some pointers/resources on this subject. Would it still be possible
> to work with Python.

Well, if you do find some hardware component that manages the JBus
interface, you've then turned your problem into "How to talk between the
PC and the JBus instrument-manager" rather than "How to talk between the
PC and JBus instruments". Depending on the protocol used by the
"instrument-manager", you may be able to use python to control that.

HTH,