COM_RTS()
 Queries or sets the Request To Send (RTS)
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 Syntax

     COM_RTS(<nComPort>,[<lNewRTSStatus>]) --> lOldRTSStatus

 Arguments

     <nComPort>  Designates the port (1 to 4) where the RTS signal is
     queried or changed.

     <lNewRTSStatus>  Designates the RTS signal status.  When the
     parameter is .T., the function activates the RTS signal.  When the
     parameter is .F., the function deactivates the RTS signal.  If no
     parameter is specified, CA-Clipper Tools does not affect the current DTR
     output signal setting.

 Returns

     The returned status corresponds to the RTS signal status prior to the
     new setting.

     A return of .T. indicates that the RTS signal is active (MCR Bit-2 = 1).
     A return of .F. indicates that the RTS signal is inactive (MCR Bit-2 =
     0).

 Description

     COM_RTS() queries or changes the status of the Request To Send signal
     (RTS).  If <lNewRTSStatus> is not specified, the RTS status remains
     unchanged.

 Note

     .  The COM_CLOSE() function resets (deactivates) the RTS signal.
        The COM_OPEN() function does not automatically activate it!

 Example

     Set an individually programmable hardware handshake:

     COM_RTS(2, .T.)      // Request to send a port 2

     DO WHILE .NOT. COM_CTS(2)
        *...
     ENDDO

     COM_SEND(2, "The quick brown fox jumps over the lazy dog")