Just found an vb example of this from an intuilink installation file
IMPORTANT NOTE: This program describes an UNSUPPORTED CAPABILITY of the
Agilent 34401 Multimeter. Agilent does not warrant or support the
performance or use of this feature in any manner.
Some customers want to measure lower ACI than the 1 A range allows. The
lowest specified measurement on the 1 A range is 1% of range, or 10 mA
(see footnote 4 in data sheet).
The code below enables a hidden 10 mA ACI range.
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10 !
20 !
30 ! The following program makes several ACI readings using
40 ! the undocumented 10 mA range.
50 !
60 ! The current range is enabled using the BUS and a DIAG:POKE 25,0,1
70 ! command. Once enabled, the range can be accessed over the
80 ! BUS or from the front panel. You can still access the range
90 ! even if power is cycled. To disable the range you need to
100 ! to send a DIAG:POKE 25,0,0 command.
110 !
120 ! BCG 1/6/93
130 !
140 Nrdgs=10 ! NUMBER OF RDGS
150 !
160 ALLOCATE Rdgs(1:Nrdgs)
170 !
180 ASSIGN @Dvm TO 723
190 !
200 ! DIG OUT PREVIOUS ERRORS
210 !
220 CLEAR 7
230 REPEAT
240 OUTPUT @Dvm;"SYST:ERR?"
250 ENTER @Dvm;A,A$
260 PRINT A,A$
270 UNTIL A=0
280 PRINT "-----------------------------------------------------------"
290 !
300 ! SET UP 34401A
310 !
320 CLEAR @Dvm
330 OUTPUT @Dvm;"*RST"
340 WAIT .5
350 !
360 !
370 OUTPUT @Dvm;"DIAG:POKE 25,0,1" ! Allows access to 10 mA
380 OUTPUT @Dvm;"CONF:CURR:AC .01,MIN" ! ACI from the bus and
390 OUTPUT @Dvm;"TRIG:COUN";Nrdgs ! front panel.
400 OUTPUT @Dvm;"READ?"
410 !
420 FOR I=1 TO Nrdgs
430 ENTER @Dvm USING "#,K";Rdgs(I)
440 PRINT I,Rdgs(I)
450 DISP I,Rdgs(I)
460 NEXT I
470 ! OUTPUT @Dvm;"DIAG:POKE 25,0,0" ! DISABLE 10 mA RANGE
480 PRINT "-----------------------------------------------------------"
490 END