HP 8360 User Handbook Manual page 334

The synthesizer uses "bumping" to move unspecified frequency
parameters, but if the final value of any of the frequency headers is
the result of bumping, then an error is generated since the user is
not getting what was specified. This means, to guarantee sequence
independence requires sending the frequency pairs in a single
message.
Example 1: (present state start = 5 GHz, stop = 6 GHz)
Example 2: (present state start = 5 GHz, stop = 6 GHz)
Example 3: (present state start = 5 GHz stop = 6 GHz)
FREQuency:CENTer <num>[freq
l
l FREQuency:CENTer? [MAXimum|MINimum]
Sets and queries the center frequency.
The *RST value is (MAX + MIN)/2.
FREQuency[:CWl:FIXed] <num>[freq
l
l
FREQuency[:FIXed]? [MAXimum|MINimum]
l
Sets and queries the CW frequency. This does not change the
swept/CW mode switch. *RST value is (MAX + MIN)/2 .
l
l
l
l
Sets and queries the CW/center frequency coupling switch. This
switch keeps the two functions coupled together when ON. Changing
one of them, changes both. *RST setting is OFF. See FREQ:CENTER
for more information.
FREQuency:MANual <num>[f req
l
l
an error results since the
stop frequency is bumped.
the final sweep does not
generate an error
(20 to 22).
no error is generated,
start frequency is unchanged.
still no error.
both are fine, no errors.
HP 8360
User's Handbook