Agilent Technologies A.18.00 User Manual

Chapter 5, Advanced Operations

Control is passed to the Test Set when it is addressed to TALK and then receives 
the Take Control Talker (TCT) command. The programming or controller 
command which implements the pass control protocol as outlined in the IEEE 
488.1 and 488.2 Standards is language/controller specific. Refer to the appropriate 
language/controller documentation for specific implementations. 

Before passing control to the Test Set the Active Controller should send the Test 
Set the address to use when passing control back. This is accomplished using the 
*PCB Common Command. The *PCB command tells the Test Set which address 
should be used when passing control back to another bus controller. Before 
passing bus control to the Test Set, the currently active controller can use the 
*PCB command to tell the Test Set where to send the Take Control (TCT) 
command when the Test Set is ready to give up active control of the bus. The 
command is followed by a number which contains the bus address of the device 
that should become the next active controller. The number must round to an 
integer in the range 0 to 30 decimal. The command may be followed by two 
numbers. The first will be used as the primary address, the second as the 
secondary address of the next active controller.