Section 15: Frequently asked questions
2470 High Voltage SourceMeter Instrument Reference Manual
15-18
2470-901-01 Rev. A /
May
2019
What does –420 "Query unterminated" error mean?
This error occurs when you address the instrument to talk and it has nothing to say. The most likely
causes are:
•
A query was not sent. You must send a valid query to the instrument before addressing it to talk.
You cannot get a reading until you send the instrument a query.
•
An invalid query was sent. If you sent a query and get this error, make sure that the instrument is
processing the query without error. For example, sending a query that generates an "Undefined
header" error and then addressing the instrument to talk will generate a "Query unterminated"
error.
•
A valid query in a command string that also contains an invalid command. This can occur when
you send multiple commands or queries in one command string (program message). When the
instrument detects an error in a command string, it discards all further commands in the
command string until the end of the string. For example, this command string would result in a
query unterminated error:
:sens:date?;:sens:func?
The first command (
:sens:date?
) generates error -113, "Undefined header" and the instrument
discards the second command (
:sens:func?
), even though it is a valid query.
How do I use the digital I/O port?
You can use the 2470 digital input/output with the trigger model or to control an external digital circuit,
such as a device handler used to perform binning operations. To control or configure any of the six
digital input/output lines, send commands to the 2470 over a remote interface.
To use the 2470 digital I/O in a trigger link system (TLINK), connect it using a 2470-TLINK Trigger
Link Cable and configure the 2470 digital input and output lines.
For more information about the 2470 digital I/O port, see
(on page 8-12).
How do I trigger other instruments?
You can use the 2470 digital input/output to control an external digital circuit, such as a device
handler used to perform binning operations. For more information about the 2470 digital I/O port, see
(on page 8-12).
You can also use the digital I/O in a trigger link system (TLINK) using a 2450-TLINK Trigger Link
Cable.
Another option is the Keithley Instruments TSP-Link
®
interface, a high-speed trigger synchronization
and communication bus that you can use to connect multiple instruments in a master and subordinate
configuration. See
TSP-Link System Expansion Interface
(on page 9-1) for additional information.