Comments - HP E1351A User Manual

Comments

Chapter 3
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
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
have not specified a different
not need to execute this command. You can also use the direct terminals
with
SCAN:PORT ABUS
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
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
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
mode selected.
TRIGger
Query Open/Closed Channels. The
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
command. The response for the
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.
Using the HP E1351A/53A FET Multiplexer Modules
SCAN:PORT NONE
is for reset and power-on. If you
NONE
SCAN:PORT since reset or power-on, you do
. The signal for a given closed channel will then
SCAN:MODE FRES
> command allows you to specify a list of channels
CLOSe? <
OPEN? <
and
OPEN? CLOSe?
command
(4-wire
channel_list and
> OPEN?
channel_list >
commands are:
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