Purpose
Returns the number of received characters available on a communications port. This function can be used to poll the COM port for data. The best way to receive characters on a COM port is to use the callback function that is set with OpenComPort or OpenComPortEx.
Parameters
Parameter: port
Type: integer
Description: The port number of the port to check or the resource number of the port to be checked if OpenComPortEx was used to open it.
Returns
Return value: number
Type: integer
Description: The number of characters available at the COM port.
Example
Visual Basic
None