WI-GTWY-9-xxx Wireless Gateway
User Manual V1.18
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An “output” is a value coming into the WI-GTWY-9-DE1 via the fieldbus (that is, a value
written to the WI-GTWY-9-DE1 from the DeviceNet master). An input is a value going out
from the WI-GTWY-9-DE1 via the fieldbus (a value read by the DeviceNet master).
So a DeviceNet WI-GTWY-9-DE1 can normally handle up to 4096 (512 x 8) discrete inputs or
512 low resolution analog inputs or 256 (512 x ½) high resolution analog inputs, or some
combination in between. It can also handle the same number of outputs; however the total I/O
count cannot exceed the WI-GTWY-9-DE1 database size of 4300.
1.1.5
Modbus Plus WI-GTWY-9-M+1
The Modbus Plus WI-GTWY-9-M+1 provides Modbus Plus Slave functionality. The Modbus
Plus connection on the WI-GTWY-9-M+1 is optically isolated RS485 with standard baudrate of
1 Mbit/sec.
The WI-GTWY-9-M+1 I/O database has 4300 registers (each of 16 bit value), however the
Modbus Plus interface only supports 1024 input registers and maximum 1024 output registers.
Each register can be 16 discrete inputs or outputs, or one analog or counter 16-bit value.
An “output” is a value coming into the WI-GTWY-9-M+1 via the fieldbus. An input is a value
going out from the WI-GTWY-9-M+1 via the fieldbus.
So an Modbus Plus WI-GTWY-9-M+1 can handle up to 4300 I/O total, but analog or pulse
inputs are limited to 1024 x 16-bit values. The same limit applies to outputs.
The Modbus Plus interface allows global data base transactions with routing for up to six
Modbus Plus networks.
1.2
The WI-GTWY-9-xxx Structure
The WI-GTWY-9-xxx has three functional sections:
•
The Radio Interface consists of an
I/O database (or "Process Image")
that maintains the latest values of
all I/O in the wireless I/O system.
The I/O database comprises 4300 x
16 bit I/O registers and 4300 x 16
bit status registers. There are also
other registers in the database that
can be used for system
management - they are discussed
later in this manual. NOTE – the
terms ‘Radio Interface’ and ‘I/O
database’ are used interchangeably
throughout the manual.
•
The radio port allows the WI-GTWY-9-xxx to communicate with other WI-GTWY-9-xxx
and/or WI-I/O 9-x modules using the WI-I/O 9-x protocol. Messages from the WI-I/O 9-x
modules are received by the radio port and used to update the input values in the WI-GTWY-
WI-GTWY-9-xxx
