troi.com – Open Serial Port (script step reference)

Troi Serial Plug-in > Script steps reference > Open Serial Port

Open Serial Port

Opens a serial port with this name and the specified parameters.

Syntax

Open Serial Port [ Select ; Result (error) ; Port name ; Settings ;
                   File name ; Script name ; Resume paused script ;
                   No idle wait time ; Match string ; Switches ]

Options

Select entire contents	replaces the entire contents of a field with the result. If not checked the result replaces the currently selected portion of the field
Result (error)	an error code
Port name	the name of the port to open
Settings	(optional) specifies the setting of the port like the speed of the port, parity, etc.
File name	(optional) the name of the FileMaker file which contains the script to trigger when data comes in
Script name	(optional) specifies the name of the script to trigger when data comes in
Resume paused script	when the trigger script needs to run, and an other script is already paused, the paused script will resume after the trigger script is finished
No idle wait time	don’t add idle wait times, the triggering will be faster, but the plug-in will need more computer time
Match string	(optional) a string that must be matched before the script is triggered
Switches	(optional) modifies the behavior of the script step

Switches

Switches can be left empty or you can add this switch:

-DontShowExtendedPrivilegeWarning

show no alert if script triggering fails

Returned Result

Data type returned

Error code

Result

Returned result is an error code. Returned error codes can be:

0	no error	the port was opened
$$-50	paramErr	there was an error with the parameter
$$-108	memFullErr	ran out of memory
$$-97	portInUse	could not open port, the port is in use
$$-4210	portDoesNotExistErr	port with this name is not available on this computer
$$-4211	allPortsNullErr	no serial ports are available on this computer

Other errors may be returned.

Originated in

Troi Serial Plug-in 5.0

Compatibility

FileMaker Pro 18 to FileMaker Pro 2025

Considerations

If you specify a filename and scriptname any scripts specified with the function “Serial_SetDispatchScript” will be ignored for this port.

If you specify a filename you must also provide a script name.

Version 6.0 added the (optional) Match string parameter, you can now specify directly when opening a port the string for which the plug-ins waits before triggering a script.

NOTE You might need to enable “Validate cross-file plug-in access” extended privilege (fmplugin extended privilege) in newly created fmp12 files, for script triggering to work.
See our web page for more info on how to do this here.

New in v9.0: the plug-in now shows an alert dialog when script triggering fails because of insufficient privilege for triggering scripts.
You can also add the switch “-DontShowExtendedPrivilegeWarning”, so no alert is shown if script triggering fails.

Example

Open Serial Port [ Select ; $ErrorCode ; "COM2" ; 
                   "baud=19200 parity=none  data=8 stop=10 " &
                   "flowControl=DTRDSR  flowControl=RTSCTS" ;
                   "" ; "" ]

will open the COM2 port with a speed of 19200 baud and the specified options.

Example 2

Set Variable [ $Settings ; gSpeed & " " & gStopBits & " " & gDataBits & " " &
                          gParity & " " & gFlowControl ]

Open Serial Port [ Select ; $ErrorCode ; 
                   gPortName1 ;
                   $Settings
                   Get ( FileName ); 
                   "Process Data Received for 1st Port" ]

Set Field [ gErrorCode ; $ErrorCode // also save into a field ]

This will open the port in field gPortName1 with the specified speed and other options. When data comes in the script “Process Data Received for 1st Port” in the current filename will be triggered. An error code is set in the $ErrorCode variable and also saved into a global field.