Gpib Controls; Gpib Address Dip Switches; Buffr Soft Key; Adrs Soft Key - Wavetek 75 Instruction Manual

To connect Model 75's in parallel, chose one as the fre-
quency master and connect its "Ref Out" to the "Ref
In" inputs of the other Model 75's. The master should
be set to internal reference and the others set to exter-
nal reference. Starting with the master unit, the "Sync
Out" output of each unit should be connected to the
"Sync In" input of its successor.
0 0 0 Q
L
0
$ J
OSCILLOSCOPE
SYNC
A R B
OUT OUT
I TRIG IN
REF IN
MODEL 75
; 7 p i L v
- -
0 7
I
1
1
A R B
O Q . a q @ ? q -
OUT
Figure 3-5. Example of Parallel Waveform
--
SYNC IN
After initial setup and after any sync position change,
each instrument must output a sync pulse before all of
the phases will be synchronized. If the test setup uses
a mode other than continuous, the outputs should be
disconnected, and the Model 75's run momentarily in
continuous mode to resynchronize the phase after a
phase change.
--
SYNC OUT
3.26 GPIB CONTROLS (Option 001 Only)
The following paragraphs are keyed to controls in figure
3-6.
3.26.1 GPIB Address DIP Switches (6)
At power on, the bit address DIP switch (located on a
PC Board under the top cover) selects the GPIB default
ADRS(address)value. This valuemay be changed from
the front panel. At power off the address returns to the
bit switch setting. See paragraph 2.2.6 bit switch
settings.
3.26.2 Setup Menu Key (4)
Pressing this key five times enables the GPlB com-
munication soft keys described below. The bottom line
of the display will then show the labels for these soft keys.
3.26.3 BUFFR Soft Key (3)
For remotely operated units the BUFFR soft key (from
the SETUP menu) will display the last 16 ASCll
characters received by the GPlB interface. Rotating the
Control knob will scroll through the last 80 ASCll
characters received by theGPIB interface.Thisfeature
can be used as a debugging tool for remote instrument
programming.
3.26.4 ADRS Soft Key (2)
Pressing this key (from the SETUP menu) allows the user
to manually set the GPlB address to some value other
than that set by the internal DIP switches.
The position of the "Sync Out" pulse from one Model
75 controls the phase of the following Model 75. There
are two ways of adjusting the position of the "Sync Out"
pulse. One is to use the "SYNC" soft key from the "Set
Up" menu to adjust the position by the actual address
or phase of the pulse itself. The other is to use the
"PHASE" soft key from the Set Up menu to adjust the
phase relationship of the successive Model 75's in
degrees. Thedifference between the two soft keys isdue
to the fact that there is a two clock cycle phase delay
from a pulse in at the "Sync In" input to the start address
output level at the output.
3.26.5 LOCAL Soft Key ( I )
Pressing this key (from the SETUP menu) brings the
Model 75 into local control providing the controller has
not locked out the key (see paragraph 3.28.1).
3.26.6 Control Knob (5)
Allows the user to scroll through the ASCII characters
received on the GPIB bus when the BUFFR soft key has
been pressed or to set theGPIBaddress when the ADRS
soft key is pressed.
Scans
by ArtekMedia O 2006