69
Bit
Summary
Bit
name
Event
Bit #
Bit
Weight
ERR
Error Event/Quere
If data is present in the Error queue, the ERR
bit will be set.
2
4
QUES Questionable Status Register
The summary bit for the Questionable Status
Register group.
3
8
MAV
Message Available
This is set when there is data in the Output
Queue waiting to be read.
4
16
ESB
Event Summary Bit
The ESB is the summary bit for the Standard
Event Status Register group.
5
32
MSS
The MSS Bit is the summary of the Status
Byte Register and Service Request register
(bits 1-5, 7). This will be set to 1.
6
64
OPER Operation Status Register
OPER bit is the summary bit for the Operation
Status Register Group.
7
128
Status Byte
Register
Any bits set in the Status byte register acts as a summary register for
all the three other status registers and indicates if there is a service
request, an error in the Error Queue or data in the Output Queue.
Reading the Status Byte register will reset the register to 0.
Service
Request
Enable
Register
The Service Request Enable Register controls which bits in the
Status Byte Register are able to generate service requests.
5-7. Error list
5-7-1. Command Errors
Overview An <error / event number> in the range [-199, -100] indicates that
an IEEE 488.2 syntax error has been detecte
d by the instrument’s
parser. The occurrence of any error in this class shall cause the
command error bit (bit 5) in the event status register (IEEE 488.2,
section 11.5.1) to be set. One of the following events has occurred:
An IEEE 488.2 syntax error has been detected by the parser. That
is, a controller-to-device message was received which is in violation
of the IEEE 488.2 standard. Possible violations include a data
element which violates the device listening formats or whose type
is unacceptable to the device.
An unrecognized header was received. Unrecognized headers
include incorrect device-specific headers and incorrect or
unimplemented IEEE 488.2 common commands.
Events that generate command errors shall not generate execution
errors, device-specific errors, or query errors; see the other error
definitions in this chapter.
