Mitsubishi FX2N RS instruction

[Kelm]

Hi

I have FX2N. I try to communicate with PC. When I use PC and VBasic , I can read and write data from/to worked by PLC.
But If I want to do it by PLC with RS instruction my tries failed.
In manuals I found an example ladder program to say TEST OK to PC.
I used hyperterminal in PC. But - No result.
What is wrong in use RS ?

Kelm

 

[Peter Nachtwey]

Here is a demo program

FX2N controlling motion controller using RS232

It uses a very simple binary protocol.

 

[sorrrrrin]

Hi

I have FX2N. I try to communicate with PC. When I use PC and VBasic , I can read and write data from/to worked by PLC.
But If I want to do it by PLC with RS instruction my tries failed.
In manuals I found an example ladder program to say TEST OK to PC.
I used hyperterminal in PC. But - No result.
What is wrong in use RS ?

Kelm

hello, could you help me sith some of your Rs instruction you used to comunicate with the vb program? maybie with the vb prog too.. or just explain to me please how it works the rs instruction program.. I want too to transmitt with a java/vb program via serial port, to the plc, data, programs.. etc, like I do with GXDeveloper for example, I know how to send/read the serial ports, but I don't know how it works the RS instruction, thanks

 

[stooperbike]

Just a tip, anytime you use the RS instruction for a FX you must load the program into the PLC, power the PLC down, then power the PLC up and place it into run. This is not clearly stated in the manuals.

 

[sorrrrrin]

please can you help me in this problem? i'm student at automation computers and electronics in romania craiova, and I'm working in a project for the faculty.

I need to develop a program let's say in java, that will let the user transmitt,receive data from the fx2n plc (like gx developer).
Not knowing the protocol, I made a program that listened gx developer how it transmitts/sends data, and reversed inginneered the data. But I found the crc which i don't know to calculate.

I think I'll try now the computer link protocol.. although the last time I tried it, it didn't work (the cause could have been not putting the plc in the run mode, when I sent the commands..?)

Could you please tell me how did you transmitt/receive data with VB? maybie you can help me with the protocol? thanks

 

[NorthControl]

Configuration

Hi!

Did you check the port configuration?
I had a problem with that, because i had the wrong cable setup.
Didn't get any error messages.... just didn't work.

However, when you're communicating through a RS232 BD card, you have to know the protocol to communicate.
If you're using ASCII codes, you must make a PLC-program to reply to your "question", since the RS instruction is a PLC command controlled by the PLC.
If you want to "ask" the PLC for data, I think you have to send a query with indexing what to get in reply. ( i think)....

 

[softwareguy]

The programming port on the Mitsubishi FX plc’s (called the front port) has a proprietary protocol. You can purchase a driver from Mitsubishi called MX-Components that will allow you to write a VB program and connect to the FX series PLC the cost of MX-Components is $500. There is a software package called Sellwood that is found here www.dwhylton.com for $299 that will allow you to build a very nice interface in minutes.