Softwarerevisionlevei; Multiplexer, Autozeroical - Keithley 199 Instruction Manual

BASIC DMM OPERATION
2.7.1 Software Revision Level
Upon entry to the DMM setup programs, the instrument
will briefly display the software revision level presently in-
stalled in the unit, as in the example below:
REV.AO.66
2.7.2 Multiplexer, Auto Zero/Cal
The multiplexer auto/cal routines may be defeated by selec-
ting this option under DMM setups. Using the Model 199
with auto zeroical defeated has two main advantages: (1)
increased measurement speed, and (2) reduced multi-
plexer effects bn high-impedance measurements.
NOTE
With the multiplexer disabled, internal calibration
and zero are affected by changes in input level,
uarticularlv on ohms and the 300V range.
tVheneverihe applied input signal changes, press
the selected function button to perform ati auto
zeroical routine; otherwise, substantial measure-
ment errors will result. Zero and calibration may
also drift with time; thus, it is recommended that
the selected function button be pressed periodica-
ly to attain optimum accuracy while auto +ero
is disabled (multiplexer off). An auto zeroical is
performed whenever the range or function is
changed.
Run this program as follows:
1. Press DMM SETUP and then NEXT as ~required until
the following message is displayed:
MUX ON
2. Use uprange or downrange to select multiplexer on/off,
as required. For multiplexer off, the instrument will
display:
MUX OFF
3. Once the desired multiplexer status is displayed, press
NFXT to scroll to the next program and save current
multiplexer status.
2.7.3 IEEE-488 Primary Address Programming
The IEEE-488 primary address program allows you check
or modify the IEEE-488 primary address of the instrument.
The factory default primary address is 26, but it can be pro-
grammed to any valid value between 0 and 30 as outlined
below. Section 3 contains detailed information on IEEE-488
programming.
Perform the following steps to use this program,
1. Press SHIFT DMM SETUP and then NEXT repeatedly
until the following message is displayed:
26 IEEE
Here we have assumed the factory default primary address
of 26.
2. ~To exit the progmm without changing the address, press
NEXT
3. To change the address, key in the desired digits~in the
range of 030, and press NEXT to go on to the following
program.
NOTES:
1. If an invalid address is entered, the primary address will
be set to 30 upon exiting the program.
2. To change the default address of the instrument, fist
set the address to the desired value, and then use the
save setup program (or send Ll over the bus). Cycling
power, or sending SDC, DCL, or LO over the bus will
not affect the newly-saved default~primary address.
3 If the IEEE-488 primary address is changed but not
saved, cycling power will return the instrument to the
original default address. However, program reset, or
DCL or SDC commands will not affect the current ad-
dress. Sending LII over the bus will not change the cur-
rent address, but it will change the default address to
the new value.
4 An "LJNCAL" error will default the address to 26 and
the line frequency setting to 60Hz.
2-w