HP 8642B User Manual

Operation Model 8642A/B
Data Input (cont'd)
Table 3-3. Relationship Between Keystrokes and HP-IB Code Sequences
Function
To set a 1 MHz
RF output frequency
To set an RF
frequency reference
of 1 MHz
To select Special
Function 111
Front-Panel Keystroke Sequence
S rr~)GD
[W] REF SET (fi^T) (W])fT~) fTl
SPCL (l^nj ( - |)(jj IjJ L±J
4iUUi^ Sequence
FR 1 MZ
FRRS 1 MZ
SP 111
Sequence
Dependency Some functions in the 8642A/B are coupled together because of internal circuit
configuration limitations. This coupling can limit the execution of a setting when one
function limits the setting of the other.
For example, amplitude and AM depth are coupled functions; An AM depth of 99.0% is
possible only when the amplitude setting is between -140.0 and +14.0 dBm. Therefore,
changing this setting: Amplitude = +14 dBm,
AM depth = 99%
to this setting: Amplitude = +15 dBm
AM depth = 7 5%
would not be possible if the amplitude entry was attempted before the AM setting. AM
could be changed first to achieve the setting, but setting AM first would not always be
successful. For example, if you were changing back to the first example (to an amplitude
of +14 dBm and AM depth of 99%), setting the AM first would not set the requested AM
setting. (To eliminate this sequence dependency problem when setting AM or amplitude,
first turn off AM, then set the amplitude, then set the AM depth.)
How to Avoid Sequence Dependency Problems
The Detailed Operating Instructions in this Operating Manual describe the limitations of
specific coupled functions and will help you avoid entering incorrect sequences. Also,
when operating locally, displayed Execution Error messages direct you to your entry error.
However, if operating via HP-IB, it might be inconvenient to rely either on the manual or
on error messages for every combination of settings. Flowcharts of Sequence Dependency,
on the following page, can assist in the development of driver subprograms to eliminate
the consequences of sequence dependency. If you follow the flowcharts and still cannot
obtain the requrested setting, that setting is probably not possible.
3-12

HP 8642B Specifications

General

Brand	HP
Model	8642B
Category	Inverter
Language	English