Beckhoff BK1120 + KL modules on Linuxcnc

Hi everyone,I am trying to get a Beckhoff BK1120 (EtherCAT to K-bus coupler) working with LinuxCNC using EtherLab (ethercat-master) and the linuxcnc-ethercat (lcec) driver.I am running into some limitations and hope someone has experience with this.Setup:

• LinuxCNC on Debian Bookworm
• EtherLab master (from openSUSE repo)
• linuxcnc-ethercat (lcec)
• NIC: Intel I210 (working fine)
• Hardware:
  • BK1120
  • KL1104 (digital inputs)
  • KL9010 end terminal

What works:

• EtherCAT master is running and stable (Active: yes, Phase: Operation)
• BK1120 is detected correctly
• Communication is stable (no frame loss, link up)

The problem:
The BK1120 does not expose standard CoE PDOs like typical EtherCAT slaves (for example EL terminals).
Instead it provides a fixed process image for the attached KL modules.Because of this:

• Standard PDO mapping via lcec XML does not work (0x6000 etc.)
• Terminal-based configs (EK1100 + ELxxxx) do not apply to KL modules
• lcec does not seem to support raw domain access for mapping the BK1120 process image directly to HAL pins

What I have tried:

• Generic slave configs with and without PDO entries
• Attempted raw mappings (not accepted by lcec parser)
• Minimal configs to bring the master up (works, but no usable I/O)
• Checking data with ethercat CLI (limited without proper domain mapping)

Current conclusion:

• BK1120 with KL modules does not fit well with lcec, which expects PDO-based slaves
• The data exists, but is not easily exposed to HAL

Questions:

• Has anyone used BK1120 with KL modules in LinuxCNC?
• Has anyone managed to access the process image and map it to HAL pins?
• Has anyone written a custom lcec extension or used another approach?

Alternatives I am considering:

• Writing a custom HAL component to read from EtherCAT master directly
• Userspace polling (not suitable for realtime CNC)

Before I give up on the BK1120, I would like to know if there is a workable solution.Any input, configs or experience would be appreciated.Thanks

Wenn ich mich Recht entsinne, funktieren die BK klemmen nicht.
Die sind das ältere Modell und verwenden ein anderes Protokoll 

The BK1120 seems to use AoE mailboxes to communicate. That is not supported by the ethercat master.
You have a big project in front of you should you decide to implement that.

Hi everyone,I am trying to get a Beckhoff BK1120 (EtherCAT to K-bus coupler) working with LinuxCNC using EtherLab (ethercat-master) and the linuxcnc-ethercat (lcec) driver.I am running into some limitations and hope someone has experience with this.Setup:

• LinuxCNC on Debian Bookworm
• EtherLab master (from openSUSE repo)
• linuxcnc-ethercat (lcec)
• NIC: Intel I210 (working fine)
• Hardware:
  • BK1120
  • KL1104 (digital inputs)
  • KL9010 end terminal
    
    
    What works:
    • EtherCAT master is running and stable (Active: yes, Phase: Operation)
    • BK1120 is detected correctly
    • Communication is stable (no frame loss, link up)
      
      The problem:
      The BK1120 does not expose standard CoE PDOs like typical EtherCAT slaves (for example EL terminals).
      Instead it provides a fixed process image for the attached KL modules.Because of this:
      • Standard PDO mapping via lcec XML does not work (0x6000 etc.)
      • Terminal-based configs (EK1100 + ELxxxx) do not apply to KL modules
      • lcec does not seem to support raw domain access for mapping the BK1120 process image directly to HAL pins
        
        What I have tried:
        • Generic slave configs with and without PDO entries
        • Attempted raw mappings (not accepted by lcec parser)
        • Minimal configs to bring the master up (works, but no usable I/O)
        • Checking data with ethercat CLI (limited without proper domain mapping)
          
          Current conclusion:
          • BK1120 with KL modules does not fit well with lcec, which expects PDO-based slaves
          • The data exists, but is not easily exposed to HAL
            
            Questions:
            • Has anyone used BK1120 with KL modules in LinuxCNC?
            • Has anyone managed to access the process image and map it to HAL pins?
            • Has anyone written a custom lcec extension or used another approach?
              
              Alternatives I am considering:

Writing a custom HAL component to read from EtherCAT master directly

Userspace polling (not suitable for realtime CNC)

Before I give up on the BK1120, I would like to know if there is a workable solution.Any input, configs or experience would be appreciated.Thanks

For every problem exist solution ... you have K-bus, something like profi-bus 

you need USB to TTL serial communication then open small doors which are for this connection, then you will need buy or made custom cabling for 4x2,54mm pins ...

you need to have KS2000 paid software which will allow to configure your EEPROM of KL1120 for existing/present members of Kbus because they are not self-identifing itselfs ... You will create configuration of whole Kbus members behind KL1120 in KS2000 and every bus member has some lenght of data .. everything in WORDs

then done mapping for ethercat PDOs and each SMs and then you can list your config over terminal build configuration tool ... then create .xml file 

finally you should run some KL stuff with non DC mode without synchronization