NAME
  OPEN COM Statement

SYNOPSIS
  OPEN "COMn: optlist1 optlist2" [FOR mode] AS [#]filenum% [LEN=reclen%]
      o n           The communications port to open (1 = COM1, 2 = COM2).
      o optlist1    The most-often-used communications parameters:
                      [baud] [,[parity] [,[data] [,[stop]]]]
                    baud is the baud rate of the device to be opened:
                      75, 110, 150, 300, 600, 1200, 2400, 4800, 9600
                    parity is the method of parity checking:
                      N (none)     E (even)    O (odd)
                      S (space)    M (mark)    PE (enable error checking)
                    data is the number of data bits per byte:
                      5, 6, 7, 8
                    stop is the number of stop bits:
                      1, 1.5, 2
                    Defaults: 300 baud, even parity, 7 data bits, 1 stop bit.
      o optlist2    A list of less-often-used parameters, separated by commas:
                    Option    Description
                    ------    --------------------------------------------------
                    ASC       Opens the device in ASCII mode.
                    BIN       Opens the device in binary mode.
                    CD[m]     Sets the timeout period (in milliseconds) on the
                              Data Carrier Detect (DCD) line.
                    CS[m]     Sets the timeout period (in milliseconds) on the
                              Clear to Send (CTS) line.
                    DS[m]     Sets the timeout period (in milliseconds) on the
                              Data Set Ready (DS) line.
                    LF        Sends a line-feed character after a carriage
                              return.
                    OP[m]     Specifies how long (in milliseconds) OPEN COM
                              waits for all communications lines to become open.
                    RB[n]     Sets the size (in bytes) of the receive buffer.
                    RS        Suppresses detection of Request to Send (RTS).
                    TB[n]     Sets the size (in bytes) of the transmit buffer.
      o mode        INPUT, OUTPUT, or RANDOM (the default).
                    See  OPEN Statement File Modes .
      o filenum%    A number in the range 1 through 255 that identifies the
                    communications channel as long as it is open.
      o reclen%     Random-access-mode buffer size (default is 128 bytes).

DESCRIPTION
  Opens and initializes a communications channel for input or output (I/O).
  The OPEN COM statement must be executed before a device can be used for
  communication using an RS232 interface.

  Example:
      'Use this example for trouble shooting serial communications problems.
      'Slow baud, hardware handshaking is ignored and buffers are enlarged.
      OPEN "COM1:300,N,8,1,CD0,CS0,DS0,OP0,RS,TB2048,RB2048" FOR RANDOM AS #1

SEE ALSO
  OPEN