FieldServer 1.1 user manual Connection Overview Error Statistics Aspect, Nak

Ruinet Utility User Manual

Page 16 of 46

2.3.4.Connection Overview - Error Statistics Aspect

Parameter	Description
Connection	The current connection being displayed out of the total number.
PEX No slave	Pex mode tried to create a cache block and failed - normally a
	failed write-through. See Driver Manual for further information
Server Overruns	A message arrived from the upstream device while the server port
	was on hold. Increase the timeout setting in the external device.
Server Hold Timeouts	If an upstream device requests data from a cache where the data
	is too old then the data will be refreshed by polling from the
	downstream device. The response was not received in time.
	A remote device never responded to the FieldServer poll. Either
	the device is not responding, or one of the timeout parameters is
Timeouts	set too low.	Ensure that the device is online and addressed
	correctly and if necessary increase the relevant timeout parameter
	in the CSV file.
Checksum Errors	External influences e.g. electrical noise corrupted the data.
	Check that communication cables are shielded, not too long and
	do not run past power cables.
Protocol Errors	An external	device responded with unexpected or	unknown
	messages. Consult the relevant driver manual.
Noise	Corrupted or garbage bytes on a communications line.
Bad Length	A message that looks Ok, but is of the incorrect length.
Bad Node	A no-response/error response from an addressable		external
	device.
Bad Function	E.g. an external device is written to that does not support writes.
No Start	Communications to an external device could not be started.
PLC exception	A variation of a NAK message produced by some protocols.
NAK	A NAK message is received in response to a poll.
	Data seems to be continuously arriving from an external device.
	This could be due to a mismatch in baud rates.
	Streaming errors are typically produced when:
Streaming	1) The transmitter sends more data than the FieldServer can
	process.
	2) An unexpectedly long message is received or messages have
	been corrupted so that the end of a previous message cannot be
	detected.
	3) A message longer than the driver expects has been received.
	A response from an external device arrived before it was
	expected, implying that it is not the response for the poll the
Premature	FieldServer has just sent. This could occur when there are time
	delays in communication networks which contain bridges and
	routers which may delay messages for longer than expected.
	Increase the timeout parameter for the connection to eliminate
	these errors.
Preamble	Characters preceding a message were dropped.
IC Timeouts	Too much time between receiving successive bytes in a message.
Address Errors	A driver tried to address a wrong device or a wrong block of data
	within an external device.
Data Object offline	A poll was received for a node that is offline.
Node Offline	An external	device node is offline in response to a	driver or

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