Keithley TEC SourceMeter 2510, User Manual

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7-20 Status Structure Models 2510 and 2510-AT User’s Manual
Error queue
The Error Queue holds error and status messages. When an error or status event occurs, a
message that defines the error/status is placed in the Error Queue.
When a message is placed in the Error Queue, the Error Available (EAV) bit in the Status
Byte Register is set. An error/status message is cleared from the Error Queue when it is
read. The Error Queue is considered cleared when it is empty. An empty Error Queue
clears the EAV bit in the Status Byte Register.
The Error Queue holds up to 10 error/status messages. The commands to read the Error
Queue are listed in
Table 7-9 . When you read a single message in the Error Queue, the
“oldest” message is read and then removed from the queue. If the queue becomes full, the
message “350, ‘Queue Overflow’” will occupy the last memory location. On power-up,
the Error Queue is empty. When empty, the message “0, No Error” is placed in the queue.
Messages in the Error Queue are preceded by a code number. Negative (-) numbers are
used for SCPI-defined messages, and positive (+) numbers are used for Keithley-defined
messages. As shown in
Table 7-9 , there are commands to read the entire message (code
and message) or the code only.
On power-up, all error messages are enabled and will go into the Error Queue as they
occur. Status messages are not enabled and will not go into the queue. As listed in
Table 7-9 , there are commands to enable and/or disable messages. For these commands,
the <list> parameter is used to specify which messages to enable or disable. The messages
are specified by their codes. The following examples show various forms for using the
<list> parameter.
<list> = (-110) Single message
= (-110:-222) Range of messages (-110 through -222)
= (-110:-222, -220) Range entry and single entry (separated by a comma)
When you enable messages, messages not specified in the list are disabled. When you dis-
able messages, each listed message is removed from the enabled list.
NOTE To prevent all messages from entering the Error Queue, send the enable com-
mand along with the null list parameter as follows: STATus:QUEue:ENABle ().