User Manual

2400 Series SourceMeter
®
User’s Manual Status and Error Messages B-9
• Incorrectly configured IEEE-488 driver. The driver must be configured so
that when talking on the bus it sends line-feed with EOI as the terminator,
and when listening on the bus it expects line-feed with EOI as the termina
-
tor. See the reference manual for your particular IEEE-488 interface.
-420, “Query UNTERMINATED”
This error occurs when you address the instrument to talk, and there is no
response message to send. The most likely causes are:
• Not sending a query. You must send a valid query to the instrument before
addressing it to talk.
• Sending an invalid query. If you have sent a query and still get this error,
make sure that the instrument is processing the query without error. For
example, sending an ill-formed query that generates an error -113, “Unde
-
fined header” and then addressing the instrument to talk will generate an
error -420, “Query UNTERMINATED” as well.
• Valid query following an invalid command. This situation can occur when
you send multiple commands or queries (program message units) within
one command string (program message). When the SourceMeter detects
an error in a program message unit, it discards all further program message
units until the end of the string; for example:
:SENS:DATE?; :SENS:FUNC?
In the above program message, the program message unit :SENS:DATE?
will generate error -113, “Undefined header,” and the SourceMeter will dis
-
card the second program message unit :SENS:FUNC? even though it is a
valid query.