INTRODUCTION
WBPEEUI250016A1
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SECTION 2 - DESCRIPTION AND OPERATION
INTRODUCTION
INFI-NET is a unidirectional, high-speed serial data highway
that can be used by all INFI 90 OPEN modules. The INNIS01
Network Interface Slave Module (NIS) and the INNPM11 Net-
work Processing Module (NPM) make up the process control
unit interface.
MODULE INTEGRITY
All INFI-NET communication modules have normal INFI 90
OPEN security functions that insure module integrity. The
module hardware checks for illegal addresses and monitors the
machine fault timer (MFT) and the I/O expander bus clock. If a
module detects an illegal address, it generates a bus error and
displays an error code on the faceplate LEDs. If the micropro-
cessor fails to reset the MFT timer, it expires. When this hap-
pens, the communication module stops and the status LED
turns red. Module hardware also monitors the I/O expander
bus clock. If there is no clock signal, the module hardware gen-
erates an interrupt.
INNIS01 NETWORK INTERFACE SLAVE MODULE
The NIS module is the communication front end for the NPM
module. This section provides an overview of INFI-NET com-
munication module operating theory.
Exception Reports
Each INFI 90 OPEN module establishes exception reporting
routes for process inputs (points). Some examples of exception
report parameters are high/low alarm limits, minimum/ maxi-
mum report time intervals, and percent of change in span.
When a point changes more than a given parameter, or an
alarm state changes, the module generates an exception
report.
The NPM module polls control modules (via the Controlway or
module bus) for exception reports, and packages together the
exception reports having a common node destination. Packing
places all exception reports for a destination (or multiple desti-
nations) into one message and the NIS module sends them to
other INFI-NET nodes as a single message. This process
reduces the number of transmissions required, and adjusts
the message size for maximum INFI-NET loop efficiency.
