Configuring the Bridge
Allow Modbus Broadcasts
This parameter specifies whether the Bridge may allow a Modbus Broadcast message to be sent to Slave devices at its serial port, or not allow those messages. Broadcast messages are those received by the Bridge containing a Unit_ID of 0 (zero).
If Modbus Broadcasts are allowed, broadcast messages are passed to the serial port as received with the Unit_ID contents of 0 (zero).
If Modbus Broadcasts are not allowed, the Unit_ID in the message is disregarded and the message is sent to Slave address 1 at the serial port.
The default is to not allow Broadcast messages to the serial port.
Character Timeout
This parameter sets the timeout value between successive characters in messages. If this timeout is exceeded, the Bridge returns an error response to the originating Master. Typically RTU protocol already contains a 3.5 character timeout, but some serial devices might have internal interrupts or other delays which can cause pauses of 5 to 10 characters during transmission. This parameter can be set to accommodate those devices.
The allowable range is 10 ... 1275 msec in 5 msec increments.
The default is 50 msec.
Message Timeout
This parameter sets the timeout value for the expected response from a Slave device. If a response is not received within this time, the Bridge continues with other tasks if any are pending from other Master devices. The Master application must provide its own method of handling the message timeout.
The allowable range is 500 ... 60000 msec (0.5 ... 60 sec) in 250 msec increments.
The default is 5000 msec (5 sec).
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