Command WriteRead :

This method permit to send a request to a device throw the serial line and returns the
response of the device.
The commands write and read don`t return until they have not finished.

WriteRead Definition
Input Argument	Tango::DEVVAR_LONGSTRINGARRAY	type of reading strategy(RAW,NCHAR..),command to write on the port com
Output Argument	Tango::DEV_STRING	response of the device behind the serial line
DisplayLevel	OPERATOR	..
Inherited	false	..
Abstract	false	..
Polling Period	Not polled	..
Command allowed for	All states	..