cip.h File Reference

CIP (Common Industrial Protocol) message codec (DETWS_ENABLE_CIP) - zero-heap request builder + response parser for the message that rides inside an EtherNet/IP Unconnected Data item (services/enip). Together they form a working CIP read path. More...

#include "ServerConfig.h"

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Detailed Description

CIP (Common Industrial Protocol) message codec (DETWS_ENABLE_CIP) - zero-heap request builder + response parser for the message that rides inside an EtherNet/IP Unconnected Data item (services/enip). Together they form a working CIP read path.

A CIP message request is:

Service(1)  RequestPathSize(1, in 16-bit words)  RequestPath(EPATH)  ServiceData

The EPATH addresses an object with logical segments. A logical segment byte is 0x20 | logical-type | format, where logical-type is class (0x00), instance (0x04), or attribute (0x10), and format is 8-bit (0x00, then a 1-octet id) or 16-bit (0x01, then a pad octet and a little-endian 2-octet id). A response is Service|0x80 reserved(0) GeneralStatus(1) AdditionalStatusSize(1, words) [additional status] ServiceData.

Service codes + the logical-segment encoding are verified against the Wireshark CIP dissector. This codec is the CIP message; wrap it with eip_build_send_rr_data.

Author

Douglas Quigg (dstroy0)

Date

2026

Definition in file cip.h.