User`s manual

Scanning a Range of Switchbox Channels
• You can scan a range of channels of a switchbox consisting of single
or multiple multiplexer modules (see Comments section for scanning
requirements of a switchbox).
• Scanning involves sequentially closing each channel on a range of
specified channels.
• During scanning, the relay which was previously closed opens before
the next relay closes.
Example: Making
Voltage
Measurements by
Scanning
Figures 3-3 and 3-4, and the following commands, show how to make
voltage measurements by performing a single scanning cycle of all channels
on two multiplexer modules in a single switchbox. In the example, the:
• Common Terminals of each terminal module connect to each other
and to the multimeter in Figure 3-5. To connect the terminals to
each other, use either the Analog Bus Cable (shown in Figure 2-2) or
wire the terminals together between each terminal modules
• Agilent E1300/E1301 Mainframe’s "Trig Out" pulse synchronizes
the switchbox with the multimeter
• GPIB Bus trigger command advances the switchbox channel list
• multimeter GPIB select code is 7 and primary address is 22
• switchbox GPIB select code is 7, the GPIB primary address is 09,
and the GPIB secondary address is 14
• computer is an HP Series 200/300 Computer with BASIC using
GPIB
Enter and Execute:
10 OUTPUT 722;"TRIG EXT;DC 10" Sets multimeter to external triggers
and to measure dc volts
20 OUTPUT 70914;"OUTP ON" Enables "Trig Out" port
30 OUTPUT 70914;"TRIG:SOUR BUS" Sets switchbox to receive Bus
triggers
40 OUTPUT 70914;"SCAN (@100:247)" Selects the channel list. 100 selects
the first channel of module #1; 247
selects the last channel of module
#2
50 OUTPUT 70914;"INIT" Starts scanning cycle
60 FOR I=1 TO 96 Start count loop
70 ENTER 722;A Enter reading into variable A
80 PRINT A Print reading in variable A
90 TRIGGER 70914 Trigger the switchbox to advance
the scan list
100 NEXT I Increment count
110 END
Chapter 3 Using the Agilent E1346A Multiplexer Module 29