This my first topic here 

Zivilin

It's easier and more clear to just declare PLC tags of the appropriate type on these addresses and use those in the code (see attachment). Provided that that there is no problem with endian-ness or other data formatting problems, of course - then you would have to engae in splitting variables and gluing them back together, as shown in your code. Information concerning profinet communication should be described in device's technical documentation, usually in some sort of communication section - the ordering of device variables in the Profinet address area, scaling etc.

Thanks Zivilin, I think if I device offset tags like you propose is much clear and simple. I have only concerns about data consistency. Actually, I can always scale the reals by some factor and scale them down in the servo (this servo can be programed with the old CodeSys v2). Becouse i still don't have the hardware I will use your approach like plan A and when i have the servo, if there is a problem I will try my idea (planB).

jacek d

A little OT.

Have you seenthis? S7 FB or Profidrive example aren't helpful?

Actually this is the place from where I started. There is example FB for com. between S7-1200 and Parker, but the FB is locked! I need some custom data to be send (the first two reals), and that's the reason that I can't used the provided example FB  - it's for simple point-to-point.

Do you think that my code snippets  looks legit, I just want to know if this is the direction ?

0_Einstein

You want asynchronous data exchange which is not telegram related.

Setting up the 3 telegram options on the Parker servo controller - at least per the pdf linked above - is what you get for synchronous "telegram" data exchange.

If you want to send other data, you need to talk to Parker for setting up custom telegrams, or how to send/receive data asynchronously (on demand)

 Don't get me wrong, I want synchronous data exchange of this 3 variables (5 words), on every cycle. I'm try to figure out how to do it - so far the solution form Zivilin looks the good one. 

In my experience, sending REAL (floating point) values directly is pretty rare in such devices. I browsed through the materials found in the link given by jacek, and found the section about communication which I would use as my starting point for creating a device-handling FB (see attachment, left side).

Immediately I see that in direct positioning mode, I will be sending three variables - a control word (STW1), a velocity setpoint (XSOLL_A) and a position setpoint (XNOM_A). Crucially, the analog values do not seem to be floating point, but 3 decimal places fixed point variables, so an integer value of, say, 1234 is sent to the servo is interpreted as a real value 1.234.

The attachment (right side) shows how I would go about constructing a basic servo-handling DB. I threw in some examples of splice access, which makes it easier to access individual bits of a word or swap bytes without resorting to shift registers. More information on splice access in the link below.

How can you access unstructured data types bit-by-bit, byte-by-byte or word-by-word and symbolically in STEP 7 (TIA Portal)? 

Zivilin

In my experience, sending REAL (floating point) values directly is pretty rare in such devices. I browsed through the materials found in the link given by jacek, and found the section about communication which I would use as my starting point for creating a device-handling FB (see attachment, left side).

Immediately I see that in direct positioning mode, I will be sending three variables - a control word (STW1), a velocity setpoint (XSOLL_A) and a position setpoint (XNOM_A). Crucially, the analog values do not seem to be floating point, but 3 decimal places fixed point variables, so an integer value of, say, 1234 is sent to the servo is interpreted as a real value 1.234.

The attachment (right side) shows how I would go about constructing a basic servo-handling DB. I threw in some examples of splice access, which makes it easier to access individual bits of a word or swap bytes without resorting to shift registers. More information on splice access in the link below.

How can you access unstructured data types bit-by-bit, byte-by-byte or word-by-word and symbolically in STEP 7 (TIA Portal)? 

Let's tell the whole story. This drive use module T40 for electronic CAM (don't ask why we use parker with simatic PLC). This module give ability to write code inside parker drive in CodeSys v2 base environment.  The servo is controlled by simple wire IO on it's input module (speeds, pos and other params are predefined  - hardcoded in servo ). We need only to change the CAM ration - and here comes the REAL numbers I want to send over Profinet. 

I found this manual . On page 462 is define Profinet communication. Now (finally) on 470 the data types are define. I saw that data type of Long Int (doble word) is the same like in S7-1200 data type DINT.

I will use  your idea. Before send something to servo I will scale it UP (Real * ScaleFactor -> DINT), and in the servo (I can write code there) I will scale it down (DINT -> REAL / ScaleFactor). It what way I think I, can address the IO image in PLC by definition of Tags (again like you show me in the first post - Plan A). 

Hope this works - will be glad to hear another opinion.