Specifications

2-6
Programming the HP 71612 Series
SCPI Command Structure
Root Keyword The Root Keyword is the top layer in the command structure. It
identifies a subsystem within a module, which is contained in the
modular measurement system.
Refer to the table Definition of Input/Output Ports on page 5-1 in the
Quick Reference Guide chapter. Each of the pattern generator and error
detector port names identifies a SCPI subsystem in the Agilent 71612
Series where the port name is used as the Root Keyword for all
commands effecting that subsystem.
There are 4 SCPI subsystems not associated with input/output ports;
FETCh/PFETch the Measurement Subsystem
DISPlay the Display Subsystem
SYSTem the System Subsystem
STATus the Status Subsystem
Some root keywords may be optional if the destination of the command
is implicit in the Command Keyword.
Command The layer below the Root Keyword is the Command Keyword. It
Keyword describes the feature on the system which is to be changed. It will
always be present in any command string and may have additional
associated commands.
Parameter The command parameters are the lowest layer in the SCPI command
structure. They may be required by the Command Keyword and are
numeric, string, boolean or block data.
Taking one command as an example we can examine this structure further.
Command Structure Example
In the following example we will examine a section of the pattern generator pattern
selection command for the Agilent 70843 Option UHG pattern generator and Agilent
70843 Option UHF error performance analyzer systems.
The pattern command can be illustrated as follows:
Root Keyword Command Keyword
Parameter(s)
[SOURce[1]:] PATTern
[:SELect] PRBS(n)|ZSUBstitut(n)
MDENsity(n)|UPATtern(n)
[:SELect]? PRBS(n)|ZSUB(n)
MDEN(n)|UPAT(n)