Command DevSerReadNBinData :

Read the specified number of char from the serial line.
If the number of caracters is greater than caracters avaiable, this command returns
all caracters avaiables.
If there are no characters to be read returns an empty array.

DevSerReadNBinData Definition
Input Argument	Tango::DEV_LONG	nb char to read
Output Argument	Tango::DEVVAR_CHARARRAY	array of data
DisplayLevel	OPERATOR	..
Inherited	false	..
Abstract	false	..
Polling Period	Not polled	..
Command allowed for	All states	..