Functions and Directives Functions and Directives

Function Com_MCR() Foundation

Sets or retrieves the Modem Control Register.

Syntax
Com_MCR( <nComPortNum>, ;
         [<nMCR>]       ;
       ) --> nMCR
Return

Com_MCR() returns the contents of the Modem Control Register as a numeric value. The function IsBit() must be used to detect which bits are set.

Com_MCR() returns always 0 since Windows does not support the contents of the Modem Control Register to be read or changed.

Description

If parameter <nMCR> is specified the Modem Control Register will be set accordingly, otherwise the current contents of the MCR will be returned.

#define constants to be used for IsBit() are found in XBTCOM.CH

Bits set in return value:
Bit Constant Description
No bit set MCR_ERROR Something went wrong
Bit 1 set MCR_DTR Data Terminal Ready is currently on
Bit 2 set MCR_RTS Request To Send is currently on

The value of all other bits depends on the features of the device driver.

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