About SNP and SNPX Communications

The SNP Communications enabler uses the Series Ninety Protocol (SNP) to communicate with Series 90 controllers over a serial line.

The SNPX Communications enabler uses the SNPX protocol to communicate with Series 90-30 controllers over a serial line.

SNP and SNPX are half-duplex protocols that uses the RS-485 (enhanced version of RS-422) and RS-232 electrical interfaces. These protocols permit communication between one master and one or more slaves. Communication between CIMPLICITY software and Series 90 controllers may be set up as a point-to-point connection or a multi-drop configuration. Connections may be established on the RS-485 CPU port of the Series 90 or via the CMM card.

Both enablers support the following CIMPLICITY features:

Polled reads at user defined rates

Poll after setpoint

Triggered reads

Analog deadband

Alarm on communications failure

Server Redundancy configurations

Both enablers support the following data types:

Signed 8, 16, and 32 bit integer

Unsigned 8, 16, and 32 bit integer

Floating point



More information

SNP and SNPX performance comparison.

Supported SNP devices.

Supported SNPX devices.

Supported SNP and SNPX memory types.

SNP hardware configuration requirements.

Required SNP and SNPX documents.

SNP and SNPX hardware installation (external).

SNP and SNPX hardware installation.

CIMPLICITY configuration for SNP and SNPX.

SNP performance notes.

SNP global parameters.

SNPX global parameters.