Serial Configuration - Df1 - Weidmuller WI-GTWY-9 User Manual

WI-GTWY-9-xxx Wireless Gateway
signal will vary between 16384 (hex 4000) and 49152 (hex C000). A 0-20mA signal will vary
between 8192 (hex 2000) and 49152 (hex C000).
Pulse I/O
Pulse counts from the remote WI-I/O 9-x modules are shown as a 16-bit register. When the
register rolls over, from 'FFFF' (hex), the next value will be '0001'. The register will only have
a value of '0000' when the remote module starts up, and the previous count is lost. This value
will indicate that the counter has reset.
Modbus Retry Delay
The WI-GTWY-9-xxx Modbus Master configuration includes a feature to limit the frequency at
which slave devices are polled for data. The WI-GTWY-9-xxx will poll each Modbus slave in
order. If there is no delay time entered, the WI-GTWY-9-xxx will poll as quickly as it is able to. If
there is a delay time entered, then this delay time will occur between each poll message.
When updated values are received from the WI-I/O 9-x radio network, the current polling sequence
is interrupted, and the new values are written immediately to the appropriate slaves.
Re-tries on the Serial Port
When communicating with Modbus slaves, the WI-GTWY-9-xxx may be configured to re-try (or
re-send) a message zero or more times if no response is received from a slave. If all retries are
used up, that slave is flagged as being in communication failure. Further attempts to
communicate with the slave will have zero re-tries. When a successful response is received from
the Modbus slave, the communication failure flag is reset and the configured number of re-tries
will be used. This means that an off-line slave device will not unduly slow down the
communications network.
Comms Fail
A "Comms Fail" image location in the WI-GTWY-9-xxx database. This image location should
be in the range 4500 to 4999. If a response is not received from the Modbus slave after all re-
tries have been sent, the WI-GTWY-9-xxx will set this Comms Fail image location to
hex(FFFF). When the WI-GTWY-9-xxx sends the next poll for this I/O Command, it will not
send any re-tries if a response is not received to the first message. When a response is eventually
received, the WI-GTWY-9-xxx will reset the value in Comms Fail image location to 0, and the
normal re-try sequence will operate.
Different I/O Commands can use different Comms Fail image locations, however we recommend
that you use the same image location for all I/O Commands to the same Modbus slave address.

4.8 Serial Configuration - DF1

The WI-GTWY-9-xxx DF1 Driver allows the WI-GTWY-9-xxx to communicate with Allen-
Bradley devices supporting the DF1 protocol. Supported commands allow communication with
500 CPU devices (SLC and Micrologix) and with PLC2 series devices. DF1 offers both full-
duplex (point to point) and half-duplex (multidrop) operation. The WI-GTWY-9-xxx only
supports the full-duplex operation - this is the default DF1 mode on most equipment. DF1 full-
duplex is a "peer-to-peer" protocol. Either DF1 device can initiate commands to the other
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