Auto/Cal Multiplex (A); Trigger Delay (W) - Keithley 199 Instruction Manual

IEEE-488 PROGRAMMING
NOTE
The complete command string will be ignored if
an IDDC, IDDCO or no ~Femdte error occurs.
The U2 command lists the Tanslator words that have been
defined by the operator. The list will be transmitted only
once each time the command is received.
The U3 command allows the user to find out the current
defined size of the buffer. The buffer size is controlled by
the I command. When this command is transmitted, the
inshument will transmit the value the next time it is ad-
dressed to talk. This information will be transmitted only
once each time the command is received. The U3 value
wiIl not be cleared when read; thus, the U3 value is always
current. For example:
sz = 010
The U4 command sends the present value. The value is
a calibration value OI zero value, as programmed by the
V command.
The U5 command sends a value that defines the status of
the input switch. A value of 0 indicates that the front panel
input terminals are selected, while a value of 1 indicates
that the rear panel input
terminals
are selected. For
example:
RF=1
Fiogammin
g Example-Enter the following statements in-
to the computer to obtain and display the machine status
word (UO).
Obtain UO status from
instrument.
Display UO states word.
Get normal reading.
Dis~lav normal readine.
1 , "
9r3 END
After entering the program, run it by pressing the RUN
key The machine conditions of the Model 199 wiIl be listed
~oii the CRT display. To show that status is transmitted on-
ly once, a normal reading is requested and displayed last.
3.9.17 Auto/+ ~Multiplex (A)
The Model 199 has built-in multiplex routines that
automatically calibrate and zero the instrument, so as to
maintain its high accuracy. The multiplex routines can be
controlled through commands below. See paragraph 2.7.2
for more information.
A0 = Disable multiplex
Al = Enable multiplex
Upon power up or after a DCL or SDC command, the in-
strument will return to the default condition.
F'mgramming Example-Disable multiplex by entering the
f6llowing statements into the computer:
When the second statement is executed, the multiplexer
routines will be disabled.
3.9.18 Trigger Delay (W)
The delay command controls the time interval that occurs
from the point the inshumenf is triggered until it begins
integration of the input signal. This feahre is useful in
situations where a specific time period must transpire to
allow an input signal to settle before measurement. Dur-
ing the delay period, the input multiplexing FETs are
switched on so the instrument is set to begin integration
upon conclusion of the programmed delay period. A delay
period can be programmed using the following command:
wn
Here, n represents the delay value in milliseconds. The
range of programmable delay values is from Omsec to
999999msec.
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