Toshiba T300MVi User Manual
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14.8.1 RS232 and RS485 Port Configuration
The RS232 and RS485 ports have the following configuration parameters:
• Protocol: Use the drop-down box to select the desired protocol to be
attached to this port.
• Baudrate: Use the drop-down box to select the desired network baudrate
(note that some protocols have a fixed baudrate and therefore ignore this
selection).
• Parity: Use the drop-down box to select the desired network parity (note
that some protocols have a fixed parity and therefore ignore this selection).
• Address: This assigns a network address to this port for the selected
protocol.
• Timeout: Defines a timeout time (in seconds) that the port uses to identify
a network timeout. 0 = timeout disabled.
14.8.2 Modbus TCP/IP Configuration
The Modbus TCP/IP protocol has the following configuration parameters:
• Enable/Disable: Enables or disables this protocol.
• Master
IP: Defines the IP address that the Modbus TCP/IP driver will
consider as its “master” for timeout purposes.
• Timeout: Defines a timeout time (in milliseconds). This network timeout
only applies to network traffic originating from the configured “master IP”
address. Valid timeout times are 500ms-30000ms (0.5s-30.0s).
Because the socket timeout determination is performed on a per-socket basis,
note that a certain degree of caution must be exercised when using the network
timeout feature to avoid “nuisance” timeouts from occurring. Specifically, do
not perform inadvisable behavior such as sending a request from the master
device to the interface, and then closing the socket prior to successfully
receiving the unit’s response. The reason for this is because the interface will
then experience an error when attempting to respond via the now-closed
socket, which will immediately trigger the timeout action. Always be sure to
manage socket life cycles “gracefully”, and do not abandon outstanding
requests.
Modbus TCP/IP sockets initiated from devices other than the “master” device
use a fixed 30s timeout time, and do not perform timeout processing. This
allows devices other than the designated “master” to access the unit for
monitoring or other non-critical access purposes.