Serial port 2 bits in and 2 bits out.
(using manual Manipulation of Serial Communication Handshake Lines and SerialStatus function).

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2 Bits Out

This ActiveX control can be used to manually manipulate the hardware handshaking lines of a serial communications port. To do this, follow the following steps.

  1. Set the state of the control line before the port is opened.
  2. Open the port.
  3. Then assert the control line to the state you wish.
'Set output
IO1.SerialRTSControl(1) 'or 0 see SerialRTSControl documentation at main web page "Functions"

          IO1.Open("COM2:", "baud=9600 parity=N data=8 stop=1")
IO1.SerialRTSControl(5) 'or 6 to change RTS state as desired.

2 Bits In


'Read input
Result = IO1.SerialStatus
If (Result And SERIAL_CTS_ON) Then
    Check1.Value = 1
    Check1.Value = 0
End If
If (Result And SERIAL_DSR_ON) Then
    Check2.Value = 1
    Check2.Value = 0
End If

Note1:SERIAL_CTS_ON and SERIAL_DSR_ON need to be defined somewhere and set to the correct values. See "Functions" and SerialStatus() for more information.

Note2: The voltages at the serial port are + and - (12 to 15 v typical).  Sometimes you can get away with 0 to 5 volts for an input but it is not guaranteed.

See: Serial and parallel cable schematics and wiring diagrams.

Copyright (c) 1998 by JSPayne