Comtrol Modbus Server - Manual (Page 35)

DeviceMaster Modbus Server User Guide: 2000535 Rev. C Embedded Diagnostic and Statistics Pages - 35
Serial Interface Communications Statistics Page
Parity Error Count
Number of parity errors received on the serial port. Typically occurs
due to an incorrect parity setting.
Framing Error Count
Number of framing errors received on the serial port. Typically
occurs due to an incorrect baud rate or stop bit setting.
Overrun Error Count
Number of overrun errors received on the serial port.. Typically
occurs to one of the following: incorrect flow control, incorrect baud
rate, incorrect data size, or incorrect stop bit setting.
Invalid RTU Device Responses
Number of invalid RTU device responses. These responses can be
caused by the following:
• Message received after the timeout period. This may require
increasing the Modbus/RTU Device Response Timeout.
• Incorrect device ID in response message.
• Incorrect function code in response message.
RTU Device Timeouts
The number of RTU device time-outs that occurred when there was
no response for a Modbus message.
Last Device Active?
The status of the last device response:
• Yes – The last message received a valid response from a device
connected to the serial port.
• No – The last message did not receive a valid response from a
device connected to the serial port
Device Transitions Inactive to
Active
The number of times a device went from the inactive state, (not
responding or no responses yet), to the active state (responding
correctly).
In a system with all devices responding correctly, this number will
typically equal the number of active devices.
Device Transitions Active to
Inactive
The number of times a device went from the active state (responding
correctly) to the inactive state (not responding correctly).
This number is intended to help identify the number times devices
respond intermittently.
Application Connection Statistics
TX Byte Count Number of bytes transmitted out of the TCP/IP connection(s).
TX Response Count (TO
application)
Number of responses transmitted out of the TCP/IP connection(s).
Dropped TX Responses
The number of responses that were intended to be transmitted out
the TCP/IP connection(s) but could not be and were dropped. This
typically occurs when one or more connections close unexpectedly.
RX Byte Count Number of bytes received on the TCP/IP connection(s).
RX Message Count (From
Application)
Number of messages received on the TCP/IP connection(s).
Dropped RX Messages Due to
Congestion
The number of messages that were dropped to the gateway being
overly congested. This typically occurs when the application(s) send
messages faster than the device(s) can respond.
Dropped Invalid or Incomplete
RX Messages
The number of messages from the application(s) that were dropped
to:
• Containing an invalid Modbus/RTU message format.
• Containing an incomplete Modbus/RU message.
Counter Name Description