Sending+a+serial+break

//by Richard Russell, July 2007//

Occasionally you may wish to send a **break** condition on a serial port output line. For example this may be needed to 'wake up' a remote device such as a modem. You can easily do that using the following code:

code format="bb4w" SYS "SetCommBreak", @hfile%(com1%) WAIT 50 SYS "ClearCommBreak", @hfile%(com1%) code Here **com1%** is the value returned from [|OPENUP] when the serial port was opened. In this example the **break** condition is maintained for about 0.5 seconds (50 centiseconds).

For completeness here is a self-contained program which opens the port, sends the break, and then closes the port:

code format="bb4w" com1% = OPENUP("COM1:9600,n,8,1") IF com1% = 0 ERROR 100, "Couldn't open serial port COM1" SYS "SetCommBreak", @hfile%(com1%) WAIT 50 SYS "ClearCommBreak", @hfile%(com1%) CLOSE #com1% code