GE 90-30 PLC Series Installation And Hardware Manual page 132

Protocols Supported
Starting with Firmware Release 9.00, breakfree SNP became the default protocol on the three
Serial Ports on these modules. See "Breakfree SNP Protocol" on page 5-13 for details.
SNP Port (Through Power Supply Connector)
Port 1 and Port 2 (Through Module's Front Panel Connectors)
GFK-0356Q Chapter 5 CPUs
SNP slave
SNP-X slave
SNP master and slave
SNP-X master and slave
RTU slave (starting with Firmware Release 8.0)
Serial I/O - Limited functionality (write only) starting with Firmware Release 8.0, will have
full functionality (read and write) starting with Firmware Release 10.0. Used with autodialer
feature to call a pager. To use this feature, configure protocol as Custom. See GFK-0582,
Series 90 PLC Serial Communications User's Manual for details.
5
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