How can I read the actual feed rate of spindle?

[NecoMai]

Hi @drunsinn I want to read the feed rate of spindle. I modify the program to read the PLC data from address 2 to 1000.

Unfortunately,  I can see the actual feed rate on the device's screen, but nothing in plc data.

I think the actual feed rate change frequently，so it doesn't write into the plc.

How can I get that feed rate of spindle ?

Thanks very much.

[drunsinn]

Hello @NecoMai,

sorry but as far as I know there is no direct command to read the current feed rates, at least TNCcmd dosen't seem to have anything.

Finding the correct PLC address is a bit of a problem because you have to know the data format first bevor checking the address space. Otherwise it is pretty difficult. You could try a different approach if you have a TNC640 or similar: Look for the symbol name of the value you need and use the function read_data_path() . This would look something like this:

lsv2.read_data_path("/PLC/program/symbol/global/MG_BA_Automatik")

If you have the passcode for your machine you can check the symbol name/path on the control by entering the PLC programming mode -> Lists -> Watchlist -> Symbol List.

[NecoMai]

Hi drunsinn I had tried to ask the supplier how I can get my want. It told me that the password in the control will be changed everyday.

    So I decided to find another way. Fortunately, I had found the open project pyLSV2. Thanks all of you.

    I found that the feed rate of spindle can be calculated this morning, so I want to read the tool's information. 

    I will have a try tomorrow morning. Thank you for your suggestion.

--

At 2022-03-23 00:17:59, "Max" @.***> wrote:

Hello @NecoMai,

sorry but as far as I know there is no direct command to read the current feed rates, at least TNCcmd dosen't seem to have anything.

Finding the correct PLC address is a bit of a problem because you have to know the data format first bevor checking the address space. Otherwise it is pretty difficult. You could try a different approach if you have a TNC640 or similar: Look for the symbol name of the value you need and use the function read_data_path() . This would look something like this:

lsv2.read_data_path("/PLC/program/symbol/global/MG_BA_Automatik")

If you have the passcode for your machine you can check the symbol name/path on the control by entering the PLC programming mode -> Lists -> Watchlist -> Symbol List.

— Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you were mentioned.Message ID: @.***>

[NecoMai]

[NecoMai]

Hi drunsinn I read the PLC address from 4 to 100000 step 4, and I had found that there is something wrong after PLC address 21480. I searched the target value from the result, I found what my want finally. That is exciting. I had found the PLC address, and I can read the feed rate of spindle from PLC now. There are something 'f' strings in table_reader.py on line 32, 44, 313, 316, 321, 351. I had contacted with the engineer of heidenhain and he told me that I need to buy the interface of DNC. A pleasant exploration experience, thank you for all of you.

[drunsinn]

Hello @NecoMai, That is really good to know it worked and you can get the values you want! It's nice to know that this little project is of use to someone!

I understand the situation as follows: The controls support two protocols for communication: LSV2 and DNC. LSV2 is the older one as it can also be used via a RS232 connection. All commands are transferred as plain ASCII codes and binary data which can be decoded with some trial and error. It's main use is/was transferring files. Thanks to the work from Eclipse-Plugin-Heidenhain it was quite strait forward to get started with pyLSV2. The newer protocol is DNC which offers a lot more functionality but also costs money to enable it on the controls and to by some development tools to write your own software. It is a higher level protocol which is a lot more difficult to reverse engineer.

The problem with the 'f' strings should also be fixed as soon as I merge pull request #25 which drops the required python version for everything to python3.4. Testing all the recent changes will take a bit more time but the new release will probably be ready soon.

[NecoMai]

The issue may be closed.