Chapter 4 Command Reference

*OPT?

(Option Identification Query)

*OPT?

(Option Identification Query)

*OPT?

Query Response

Comments

Queries the instrument to identify any installed options.

The following options can be installed in the instrument:

Option 001, Medium Stability Oven Timebase

Option 010, High Stability Oven Timebase

Option 012, Ultra High Stability Oven Timebase

Option 030, 3.0 GHz RF Input Channel (Channel 3)

Option 050, 5.0 GHz RF Input Channel (Channel 3)

A sequence of ASCII-encoded bytes, indicating <timebase option>, <3.0 GHz RF Input option> terminated with a new line and EOI.

– The <timebase option> is 001, 010, or 0.

Note that the counter responds with 010 for either the high stability or ultra high stability oven timebase.

– The <3.0 GHz RF Input option> is 030 or 0.

Note that the counter responds with 030 for either the 3.0 GHz or 5.0 GHz RF Input option.

– A missing option is identified by an ASCII 0 (zero).

For example, if only the medium stability timebase option is detected, the response would be: 001,0.

This query should be the last query in a terminated program message; otherwise, error -440 is generated.

4-134

Programming Guide