Returns the data available at a COM port. The data is a variant and could be a text string or an array of bytes, depending on the type of data available. This function is not used if the COM port is opened in mode 1. If the port is opened as mode 0, this function should be used in your callback function to get the data.
Description: The COM port to read or the resource number of the port to be read if OpenComPortEx was used to open it.
Return value: data
Description: The data available is a string of characters.