 // SCPI tree
 /*
  **** NOTE :SYSTEM:ERROR must be registered (also SYS  & ERR)
   * Command tree
   *  *IDN?          				-> identify (pre-registered in library code)
   *** *TST?						-> run self test (pre-registered in library code?)
   *  :INSTrument
   *    :NAME  		<string>      	-> set name
   *    :NAME?       				-> get name

   *	:ESTOP		 				-> turn all channels on this instrument OFF
   *  :SOURCce						-- Control values
   *    :VOLTage  	<float[V]>  	-> set_voltage
   *    :VOLTage?    				-> get set_voltage
   *    :CURRent   	<float[A]>  	-> set_current
   *    :CURRent?    				-> get set_current
   *    :POWEr?    					-> get set_power
   *    :POWEr   	<float[W]>  	-> set_power   
   *    :RESIstance?    			-> get set_resistance
   *    :RESIstance  <float[A]>  	-> set_resistance   
		:STATe	-> output on/off
   LOGTime
   :FUNCTION
	 :BATTery
		:STEP
			:ACURrent
			:BCURrent
			:AVOLtage
			:BVOLtage
			:ATIMe
			:BTIMe
			:ASTEps
			:BSTEps
			:SLEW
			:CYCLes
		
   *  :MEASure						-- Instrument readings
   *    :VOLTage?    				-> get_voltage
   *    :CURRent?    				-> get_current
	   :POWEr?
	   :RESIstance?
      * 	:TEMP?		 				-> get heatsink temperature
:WATThours?
:AMPHours?
:BATStartr
:BATEndr
:WAVEdata?
*/