Device control string syntax
The device-control string uses the syntax of the mode command. The string must have the same form as the mode command's command-line arguments. For further information on mode command syntax, refer to the end-user documentation for your operating system.
Syntax
modecomm[:] [baud=b] [parity=p] [data=d] [stop=s] [to={on|off}] [xon={on|off}] [odsr={on|off}] [octs={on|off}] [dtr={on|off|hs}] [rts={on|off|hs|tg}] [idsr={on|off}]Parameters
com m[:]  | Specifies the number of the port for asynchronous communications (COM).  | 
baud= b  | Specifies the transmission rate in bits per second. The following table lists valid abbreviations for b and its related baud rate. 
  | 
parity= p  | Specifies how the system uses the parity bit to check for transmission errors. The following table lists the valid values: p. The default value is e. Not all computers support the values m and s. 
  | 
data= d  | Specifies the number of data bits in a character. Valid values for d are in the range 5 to 8. The default value is 7. Not all computers support the values 5 and 6.  | 
stop= s  | Specifies the number of stop bits that define the end of a character: 1, 1.5 or 2. If the baud rate is 110, the default value is 2. Otherwise, the default value is 1. Not all computers support the value 1.5.  | 
to={on|off}  | Specifies whether the endless timeout processing is on or off. The default value is off.  | 
xon={on|off}  | Specifies whether the xon or xoff protocol for data-flow control is on or off.  | 
odsr={on|off}  | Specifies whether output handshaking that uses the Data Set Ready (DSR) signal is on or off.  | 
octs={on|off}  | Specifies whether output handshaking that uses the Clear To Send (CTS) signal is on or off.  | 
dtr={on|off|hs}  | Specifies whether the Data Terminal Ready (DTR) signal is on or off, or set to handshake.  | 
rts={on|off|hs|tg}  | Specifies whether the Request To Send (RTS) signal is set to on, off, handshake or toggle.  | 
idsr={on|off}  | Specifies whether the DSR signal is used or not.  | 
Things to know:
- For a string such as 96,n,8,1 or any other older-form mode string that doesn't end with an x or a p:
 - fInX, fOutX, fOutXDsrFlow and fOutXCtsFlow are all set to FALSE
 - fDtrControl is set to DTR_CONTROL_ENABLE
 - fRtsControl is set to RTS_CONTROL_ENABLE
 - For a string such as 96,n,8,1,x or any other older-form mode string that ends with an x:
 - fInX and fOutX are both set to TRUE
 - fOutXDsrFlow and fOutXCtsFlow are both set to FALSE
 - fDtrControl is set to DTR_CONTROL_ENABLE
 - fRtsControl is set to RTS_CONTROL_ENABLE
 - For a string such as 96,n,8,1,p or any other older-form mode string that ends with a p:
 - fInX and fOutX are both set to FALSE
 - fOutXDsrFlow and fOutXCtsFlow are both set to TRUE
 - fDtrControl is set to DTR_CONTROL_HANDSHAKE
 - fRtsControl is set to RTS_CONTROL_HANDSHAKE