Comments
Isolation. The direct terminals provide a more accurate measurement than
the tree terminals or the analog bus connector as the signal does not have to
travel through the extra FET switches. The
SCAN:PORT NONE
command
opens the tree isolation switches and isolates the direct terminals from the
tree terminals and the analog bus connector.
The default value of
SCAN:PORT
is
NONE
for reset and power-on. If you
have not specified a different
SCAN:PORT
since reset or power-on, you do
not need to execute this command. You can also use the direct terminals
with
SCAN:PORT ABUS
. The signal for a given closed channel will then
be available at the direct terminal for that bank, the A tree terminal and the
analog bus connector.
Closing Channels. The FET multiplexer module only allows one channel
per card to be closed at a time, except for
SCAN:MODE FRES
(4-wire
resistance measurements) where two channels are closed. You can close a
channel on two different cards in the same instrument at the same time.
The
SCAN <
channel_list
>
command allows you to specify a list of channels
to be closed sequentially. The FET multiplexer module uses a
break-before-make procedure, so closed channels are opened before the
next one on the list is closed. The channels are advanced according to the
TRIGger
mode selected.
Query Open/Closed Channels. The
CLOSe? <
channel_list
>
and
OPEN?
<
channel_list
>
commands determine if the channel(s) in the channel list are
open or closed, respectively. (The query command does not determine if, in
the event of a hardware failure, the channel remains open/closed.) For
example, to determine if channel 109 is closed, execute:
CLOS? (@109)
A response of "1" indicates the channel is closed, and a "0" indicates the
channel is open. The reverse is true for the
OPEN? <
channel_list
>
command. The response for the
OPEN?
and
CLOSe?
commands are:
CLOS?
1 = Closed
0 = Open
OPEN?
1 = Open
0 = Closed
To find out which channel on a card is closed, use a channel list for the card.
CLOS? (@100:115)
and enter the response into a string variable. If channel 09 is closed, the
response will be:
0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0
NOTE: You must read the response after sending a query command or
the switchbox will generate an error.
Chapter 3
Using the HP E1351A/53A FET Multiplexer Modules 33
Summary of Contents for E1351A
Page 4: ...Notes 4 HP E1351A 53A FET Multiplexer User s Manual Contents ...
Page 8: ...Notes 8 HP E1351A E1353A 16 Channel FET Multiplexer Modules User s Manual ...
Page 10: ...10 HP E1351A 53A 16 Channel FET Multiplexer Module User s Manual ...
Page 28: ...Notes 28 Configuring the HP E1351A 53A FET Multiplexer Modules Chapter 2 ...
Page 78: ...Notes 78 HP E1351A 53A 16 Channel FET Multiplexer Command Reference Chapter 5 ...
Page 80: ...Notes 80 HP E1351A 53A FET Multiplexer Specifications Appendix A ...
Page 100: ...Notes 100 HP E1351A 53A FET Multiplexer Error Messages Appendix C ...