Keithley 2182, User Manual, Page: 210 / 339

12-6 Common Commands
*ESR? – Event Status Register Query
Read register and clear it
Description
Use this command to acquire the value (in decimal) of the Standard Event Register (see
Figure 12-2 ). The binary equivalent of the returned decimal value determines which bits in the
register are set. The register is cleared on power-up or when *CLS is sent.
A set bit in this register indicates that a particular event has occurred. For example, for an
acquired decimal value of 48, the binary equivalent is 00110000. From this binary value, bits B4
and B5 of the Standard Event Status Register are set. These bits indicate that a device-dependent
error and command error have occurred.
The bits of the Standard Event Status Register are described as follows:
• Bit B0, Operation Complete – A set bit indicates that all pending selected device
operations are completed and the Model 2182 is ready to accept new commands. This
bit only sets in response to the *OPC? query command.
• Bit B1 – Not used
• Bit B2, Query Error (QYE) – A set bit indicates that you attempted to read data from an
empty Output Queue.
• Bit B3, Device-Dependent Error (DDE) – A set bit indicates that an instrument operation
did not execute properly due to some internal condition.
• Bit B4, Execution Error (EXE) – A set bit indicates that the Model 2182 detected an error
while trying to execute a command.
• Bit B5, Command Error (CME) – A set bit indicates that a command error has occurred.
• Command errors include:
• IEEE-488.2 syntax error – Model 2182 received a message that does not follow the
defined syntax of the IEEE-488.2 standard.
• Semantic error – Model 2182 received a command that was misspelled or received
an optional IEEE-488.2 command that is not implemented.
• The instrument received a Group Execute Trigger (GET) inside a program message.