Debugging a COMx Driver

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Debugging a COMx Driver

A COMx driver is the board driver typically used for serial communications. Since version 2.01, the COMx driver allows you to dump debug information.

Three files are produced for each com port: a write file, a read file and status file. The debug files are configured by settings in the Citect.ini and are written and are written to the path specified in [CtEdit]Logs.

The following Citect.ini entries are used:

Parameter	Default	Comments
WritePortName	(no value)	Port name as defined in the Ports form
WriteFileSize	1000	Size in KB
WriteDebugLevel	0	1 to enable debugging, 0 to disable
ReadPortName	(no value)	Port name as defined in the Ports form
ReadFileSize	1000	Size in KB
ReadDebugLevel	0	1 to enable debugging, 0 to disable
StatusPortName	(no value)	Port name as defined in the Ports form
StatusFileSize	1000	Size in KB
StatusDebugLevel	0	1 to enable debugging, 0 to disable
CharTimeOut	11	CharTimeOut specifies the maximum acceptable time (in milliseconds) to elapse between the arrival of two characters on the communication line. During a ReadFile operation, the time period begins when the first character is received. If the interval between the arrival of any two characters exceeds this amount, the ReadFile operation is finished and any buffered data is returned. A value of zero indicates that interval time-outs are not used.
PassIfAnyInitPortsPass	0	Set to 1 if you wish to start when a COMx port is missing.

Example

[COMx]
WritePortName=PORT_1,PORT_2
WriteDebugLevel=1
WriteFileSize=2000
ReadPortName=PORT_1
ReadDebugLevel=1
ReadFileSize=1000
StatusPortName=PORT_2
StatusDebugLevel=1
StatusFileSize=10

The above example would:

Log to "write" files up to 2000 kb of the data sent by the Citect SCADA driver to both PORT_1 and PORT_2;
Log to a "read" file 1000 kb of the data received by the Citect SCADA driver from PORT_1; and
Log up to 10 kb of status data from PORT_2 to a "status" file.

This would also result in the following text files being created:

WPORT_1.dat
WPORT_2.dat
RPORT_1.dat
SPORT_2.dat

In general, the format for the file names is "R", "W" or "S" followed by the Port name requested, followed by ".dat". The file names represent the corresponding "Read", "Write" and "Status" files.

Published June 2018