SPRADH0 August   2024 AM625 , AM6442 , AM69 , TDA4VM

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 What is EtherCAT?
    2. 1.2 What is a PLC?
    3. 1.3 What is CODESYS?
  5. 2Evaluation Platform and Methods
    1. 2.1 Hardware
    2. 2.2 Software
    3. 2.3 Test Topology
  6. 3Performance Metrics
    1. 3.1 Cyclictest Performance Metrics
    2. 3.2 EtherCAT Performance Metrics
  7. 4Optimizations
    1. 4.1 Implemented Optimizations
    2. 4.2 Future Considerations
      1. 4.2.1 Set Maximum CPU Frequency
      2. 4.2.2 Isolate Cores
      3. 4.2.3 Set CPU Affinity
      4. 4.2.4 Isolate Cores and Set CPU Affinity
      5. 4.2.5 Ksoftirqs to FIFO
      6. 4.2.6 Increase the Real-Time Scheduling Time
      7. 4.2.7 Disable irqbalance
      8. 4.2.8 Use Separate Network Interface Card (NIC)
      9. 4.2.9 Disable Unnecessary Drivers
  8. 5Summary
  9. 6References
  10. 7Appendix A: How to Setup TI Embedded Processors as EtherCAT Controller Using the CODESYS Stack
    1. 7.1 Hardware Requirements
    2. 7.2 Software Requirements
    3. 7.3 Hardware Setup
    4. 7.4 Software Setup
      1. 7.4.1 Windows PC Setup
      2. 7.4.2 EtherCAT Controller Setup
      3. 7.4.3 CODESYS Development System Project
      4. 7.4.4 Execution
    5. 7.5 How to View Performance Measurements
      1. 7.5.1 Appendix A Resources
  11. 8Appendix B: How to Enable Unlimited Runtime on CODESYS Stack
    1. 8.1 CODESYS Licensing Background
    2. 8.2 Obtaining a CODESYS License
    3. 8.3 Activating CODESYS License
      1. 8.3.1 Background
      2. 8.3.2 Recommended Steps
    4. 8.4 Verifying CODESYS License Applied
      1. 8.4.1 Known Issues With Verifying CODESYS License Applied

4.2.5 Ksoftirqs to FIFO

By default, ksoftirqs associated with each core are scheduled as “TS”, “time-sliced”, “time-sharing”, or “SCHED_OTHER” scheduling policy (these are four different names for the same scheduling policy). This is a standard round-robin time-sharing policy that is intended for all processes that do not require special real-time mechanisms. Since ksoftirqs are used by ethernet-related interrupts that EtherCAT packets use, verifying that ksoftirqs are scheduled with as high a priority as possible in a real time scheme is important. Therefore, change from “TS” to “FIFO”, where possible. In other words, use “SCHED_FIFO” with priority higher than the -56 the EtherCAT task is set to. This procedure can be performed with the chrt -f -p <priority> <process id> command.