Posted 31 Aug 2016 Hi all, I know it's internal for GE, but anyone has the protocol spec or technical reference ? Share this post Link to post Share on other sites
Posted 31 Aug 2016 Hello, I never found a published specification when I was looking for one several years ago. IIRC it was much like SNPX with an attach and establish session handshake before reading/writing data. Also, I do not recall if Wireshark had a dissector for SRTP. You can use the demo of PeakHMI and in configuration mode capture the handshake and read commands. For write commands you would need to create points/tags and issue writes at runtime, still using the demo version. Share this post Link to post Share on other sites
Posted 31 Aug 2016 Much like Modbus TCP is Modbus RTU for Ethernet, SRTP in GE's SNP protocol for Ethernet. Share this post Link to post Share on other sites
Posted 31 Aug 2016 Hello Yeah, it is "much like." SRTP has much more overhead and has a session establish handshake after the attach. SNP only the attach IIRC. Also like MODBUS TCP/RTU, the serial protocol has a CRC/LRC and the TCP protocol does not. Share this post Link to post Share on other sites