Mainframes User's Manual

1
GPIB Message
Reference
This section describes IEEE-488.1 defined messages and their affect on
instruments installed in the mainframe. The examples shown are specifically for
HP 9000 Series 200/300 computers using BASIC language. Any IEEE-488
controller can send these messages; however, the syntax may be different from
that shown here.
Go To Local (GTL) Places an instrument in local state.
Comments • Refer to the Local Lockout message, later in this chapter, for information
on how GTL affects front panel lockout.
Examples LOCAL 7 Sets GPIB remote enable line
false (all instruments go to
local). (You must now execute
REMOTE 7 to return to remote
mode).
LOCAL 70900 Issues GPIB GTL to System
Instrument. (The instrument
will return to remote mode
when it is listen addressed.)
Group Execute Trigger
(GET)
Executing a group execute trigger will trigger an instrument assuming the
following conditions are true:
• The instrument’s trigger source is set to Bus (TRIG:SOUR BUS
command), and:
• The instrument is in the Wait For Trigger state, and:
• The instrument is addressed to listen (can be done by sending any
command, the REMOTE 709ss (ss = secondary address) command, or
with the LISTEN command).
Comments • For instruments in an Agilent E1300B/E1301B Mainframe, only one
instrument at a time can be programmed to respond to GET. This is
because only one instrument can be addressed to listen at any one time.
Example 10 OUTPUT 70900;"TRIG:SOUR BUS" Sets trigger source to bus
20 OUTPUT 70900;"INIT:IMM" Places System Instrument’s
Pacer in Wait For Trigger state
30 TRIGGER 70900 T riggers Pacer
40 END
Interface Clear (IFC) Unaddresses all instruments in the mainframe and breaks any bus handshaking
in progress.
Example ABORT 7
7-72 System Instrument Command Reference