A simple C++ EtherCAT master stack.

Kick-start your slaves!

Current state:

• Can go to OP state
• Can read and write PI
• CoE: read and write SDO - blocking and async call
• CoE: Emergency message
• Bus diagnostic: can reset and get errors counters
• hook to configure non compliant slaves
• consecutives writes to reduce latency - up to 255 datagrams in flight

TODO:

• CoE: segmented transfer - partial implementation
• CoE: diagnosis message - 0x10F3
• Bus diagnostic: auto discover broken wire (on top of error counters)
• Link: handle interface redundancy
• More profiles: FoE, EoE, AoE, SoE
• Distributed clock
• AF_XDP Linux socket to improve performance

Latency

To improve latency, you have to

• use Linux RT (PREMPT_RT patches),
• set a real time scheduler for the program (i.e. with chrt)
• disable NIC IRQ coalescing (with ethtool)
• disable RT throttling
• isolate ethercat task and network IRQ on a dedicated core
• change network IRQ priority

EtherCAT doc

https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_io_intro/1257993099.html&id=3196541253205318339 https://www.ethercat.org/download/documents/EtherCAT_Device_Protocol_Poster.pdf

registers: https://download.beckhoff.com/download/Document/io/ethercat-development-products/ethercat_esc_datasheet_sec2_registers_3i0.pdf

eeprom : https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_io_intro/1358008331.html&id=5054579963582410224

various: https://sir.upc.edu/wikis/roblab/index.php/Development/Ethercat

diag: https://www.automation.com/en-us/articles/2014-2/diagnostics-with-ethercat-part-4 https://infosys.beckhoff.com/english.php?content=../content/1033/ethercatsystem/1072509067.html&id= https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000kHwESAU