Specifications

3-9
Interrogating the Instrument Status
Standard Event Status Register Group
Operation The operation complete bit, bit 0, is set in response to the *OPC
Complete Bit command if the instrument has completed all its pending
operations.
Request Control This bit is not used in this instrument.
Bit
Query Error Bit The query error bit, bit 2, indicates there is a problem with the
output data queue. Either there has been an attempt to read the
queue when it is empty or the output data has been lost.
Device Dependent The device dependent error bit, bit 3, is set when an error of some
Error Bit kind has occurred in the instrument.
Execution Error The execution error bit, bit 4, is set when a command (GP-IB
Bit instrument specific) cannot be executed due to an out of range
parameter or some instrument condition existing that prevents the
execution. For example, the instrument is already set to the wrong
range.
Command Error The command error bit, bit 5, is set whenever the instrument detects
Bit an error in the format or content of the program message (usually a
bad header, missing argument, or wrong data type etc.).
Power On Bit The power on bit, bit 7, is set each time the instrument is powered
from off to on.
The Standard Event register can be interrogated using the *ESR? common query
command. It is an event register which is cleared after it is read.
OUTPUT 718;“*ESR?”
ENTER 718;Event_reg$
PRINT Event_reg$
Requests the contents of the Standard Event register. The Standard Event Register may
also be cleared without having to interrogate it. This is done by using the “*CLS”
command.
Standard Event Enable Register
The Standard Event Enable register is a 16 bit register which acts as a mask on the
Standard Event Status register. It allows one or more event bits in the Standard Event
register to set the ESB summary bit, bit 5, in the Status Byte.
For example, if bit 0 is set in the Standard Event Enable register, then, when the OPC bit
in the Standard Event register goes true, the ESB summary bit is set in the Status Byte.
The Standard Event Enable register is set using the “*ESE” command. The following
gives an example of setting bit 0, 1 and 2 in the Standard Event Enable register.
OUTPUT 718; “*ESE 7”