Number And Conflict Errors - Keithley 595 Instruction Manual

IEEE-488 PROGRAMMING
mand option is received. For example, the command T9X
has an invalid option because the instrument has no such
+qger mode.
HP-85 Programming Fxample-To demons&ate a bus error,
send an IDDC with the following statements:
When the second statement is executed, the bus error
message appears on the display for about one second.
4.7.2 Trigger Overrun Error
A tripger overrun error occurs when the instrument receives~
a trigger while it is making a measurement conversion. Note
that only the overrun triggers are ignored and will heve no
effect on the instrument except to generate the message
below. When a trigger overrun occurs, the following front
panel message will be displayed for approximately one
second:
tErr
The instrument can be programmed to generate an SRQ
when a trigger overrun occurs (see paragraph 4.9.20). Also,
the TRIGGER OVERRUN bit in the Ul status word will be
set when the error occurs (see paragraph 4.9.23).
HP-85 Progra mmfng Example-To demonstrate a trigger
overrun error, enter the following statements into the HF-85
keyboard:
REtWTE 728
OLITPIJT 728; i i T3Xv 5
TRIGGEF:728@TRIGGERi2E:
Note that the trigger overrun message is displayed when
the third statement is executed.
4.7.3 Number and Conflict Errors
A front panel error message is used to flag a number error
or conflict error. A number error occurs when an out of
range calibration value (A) or voltage source value (V, H,
L) is sent over the bus. A conflict error occurs when the
Q or C command is sent while the instrument is in the cur-
rent function (FL). A number or conflitierror will cause the
command to be ignored (but not theentire string if all else
is legal) and the following message will be displayed briefly:
nErr
The ,mstrument can be programmed to generate an SRQ
when a number or conflict error occurs (see paragraph
4.920).
Also, the NUMBER and CONFLICT bits in the Ul
error status word will be set when the appropriate error
occurs (see paragraph 4.923).
HP-85 Programming Example-To demonstrate a number
error, enter the following statements into the computer:
When END LINE is pressed the second time, a number
error will occur because the voltage source cannot be set
to
21v.
4.7.4 Waiting for Trigger
When a trigger command (TnX) is sent over the bus, the
instrument will stop making measurements and display the
"waiting for trigger" message. The decimal point; and
range/function mnemonics or exponent are also displayed
to define the present operating state. For example, with the
instrument on the 20nF range, sending 'I3 over the bus will
result with one of the following messages being displayed~:
t.riG nF
.tri:-a
When the voltage source is set for off, DC or square-wave
output, measurements will continue when the required
trigger Occurs. If a trigger command is sent while a stair-
case is in process, the voltage source will Seth to-a DC out-
put. To continue the staircase output, first set the voltage
source for a staircase output @VS) and then apply the re-
quired trigger. See paragraph 4.9.19 for detailed informa-
tion on triggers.
HP-85 Programming Example-Enter the following
statements into the computer to demonstrate the "waiting
for trigger" message when the instrument is placed in one-
shot, triggered by GET.
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