National Instruments 320682C Musical Toy Instrument User Manual


 
Chapter 5 RS-232 Library
© National Instruments Corporation 5-21 LabWindows/CVI Standard Libraries
Parameter
Input
COMPort
integer Range 1 through 32.
Return Value
len
integer Number of characters in the
input queue.
Parameter Discussion
The function returns an error if the port is not open or if COMPort is invalid.
GetOutQLen
int len = GetOutQLen (int COMPort);
Purpose
Returns the number of characters in the output queue of the specified port.
Parameter
Input
COMPort
integer Range 1 through 32.
Return Value
len
integer Number of characters in the
output queue.
Using This Function
You can use this function to ensure the output queue has emptied before you close the port. This
function has no effect on the output queue.
The function returns an error if the port is not open or if COMPort is invalid.