GE PACE Series User manual

GE
Measurement & Control
PACE
Pressure Automated Calibration Equipment
SCPI Remote Communications Manual - K0472 Revision A
PACE1000
PACE5000
PACE6000
g

© 2015 General Electric Company. All Rights Reserved. Specifications are subject to change without
notice. GE is a registered trademark of General Electric Company. Other company or product names
mentioned in this document may be trademarks or registered trademarks of their respective companies,
which are not affiliated with GE.

K0472 Revision A i
Introduction
This technical manual provides SCPI protocol instructions for the remote control of the
PACE Series indicators and controllers.
Safety
The manufacturer has designed this product to be safe when operated using the
procedures detailed in this manual. Do not use this product for any other purpose than
that stated.
This publication contains operating and safety instructions that must be followed to
make sure of safe operation and to maintain the equipment in a safe condition. The
safety instructions are either warnings or cautions issued to protect the user and the
equipment from injury or damage.
Use qualified* programming technicians and good engineering practice for all
procedures in this publication.
Pressure
Do not apply pressure greater the maximum safe working pressure to the PACE Series.
Maintenance
The PACE Series must be maintained using the manufacturer’s procedures and should be
carried out by authorised service agents or the manufacturer’s service departments.
Technical Advice
For technical advice contact the manufacturer or subsidiary.
*A programming technician must have the necessary specialist knowledge of
programming, technical knowledge and documentation to carry out the required work
on the PACE Series.
Associated Documents:
A beginners Guide To SCPI by Barry Eppler, Published by Addison-Wesley Publishing
Company Inc. for Hewlett Packard (ISBN 0-201-56350-9)
This issue of the manual
This manual details the SCPI commands and queries for the PACE1000, PACE5000 and
PACE6000 pressure instruments. This issue removes erroneous code and clarifies the
operation status group (3.3).

ii K0472 Revision A
Table of Contents
Preliminary pages
Introduction .................................................................................................................................i
Safety .................................................................................................................................i
Table of contents (this table)..........................................................................................................................ii
List of Illustrations .................................................................................................................................vi
List of Tables .................................................................................................................................vii
Abbreviations .................................................................................................................................vii
Pressure measurement units.........................................................................................................................viii
Code Definitions .................................................................................................................................vii
Pressure unit conversions...............................................................................................................................viii
Section page
1 INTRODUCTION ............................................................................................................1-1
1.1 General ................................................................................................................................... 1-1
1.2 Remote/Local Operation . .............................................................................................................................1-1
2 COMMAND STRUCTURE ................................................................................................2-1
2.1 Notation ...................................................................................................................................2-1
2.2 Message Terminators............................................................................................................................. 2-1
2.3 Program headers ...................................................................................................................................2-3
2.4 SCPI data types ...................................................................................................................................2-4
3 STATUS SYSTEM ............................................................................................................3-1
3.1 Output queue ...................................................................................................................................3-3
3.2 Standard event group ................................................................................................................................. 3-4
3.3 Operation status group ............................................................................................................................ 3-5
3.4 Status byte group ....................................................................................................................................... 3-7
3.5 Instrument errors ....................................................................................................................................... 3-10
4 COMMAND and QUERY SUMMARY.................................................................................. 4-1
4.1 Command structure................................................................................................................................4-1
CALibration ...................................................................................................................................4-3
:CAL:PRES:POIN ...................................................................................................................................4-3
:CAL:PRES:ACC ...................................................................................................................................4-4
:CAL:PRES:ABOR ...................................................................................................................................4-5
:CAL:PRES:VAL ................................................................................................................................... 4-6
:CAL:PRES:ZERO:VALV..............................................................................................................................4-7
:CAL:PRES:ZERO:AUTO............................................................................................................................. 4-8
:CAL:PRES:ZERO:TIME .............................................................................................................................. 4-9
:CAL:PRES:ZERO:TIME:STAT.................................................................................................................... 4-10

K0472 Revision A iii
DISPlay .................................................................................................................................4-11
DISP:WINDow .................................................................................................................................4-11
INPut .................................................................................................................................4-12
INP:LOG .................................................................................................................................4-12
INP:LOG:STAT .................................................................................................................................4-13
INSTrument .................................................................................................................................4-14
:INST:CAT:ALL .................................................................................................................................4-14
:INST:CONT:SENS .................................................................................................................................4-15
:INST:DISP .................................................................................................................................4-16
:INST:LIM .................................................................................................................................4-17
:INST:MAC .................................................................................................................................4-19
:INST:SENS .................................................................................................................................4-20
:INST:SENS:CALD .................................................................................................................................4-21
:INST:SENS:FULL .................................................................................................................................4-22
:INST:SENS:NEG .................................................................................................................................4-23
:INST:SENS:READ .................................................................................................................................4-24
:INST:SENS:SN .................................................................................................................................4-25
:INST:SENS:ZERO .................................................................................................................................4-26
:INST:SN .................................................................................................................................4-27
:INST:TASK .................................................................................................................................4-28
:INST:TASK:AERO .................................................................................................................................4-29
:INST:UNIT .................................................................................................................................4-30
:INST:VERS .................................................................................................................................4-31
OUTPut .................................................................................................................................4-32
:OUTP:STAT .................................................................................................................................4-33
:OUTP:LOG .................................................................................................................................4-34
:OUTP:ISOL:STAT .................................................................................................................................4-35
SENSe .................................................................................................................................4-36
SENS:ALT .................................................................................................................................4-36
SENS:ALT:INL .................................................................................................................................4-37
SENS:ALT:INL:TIME .................................................................................................................................4-38
SENS:ALT:RANG .................................................................................................................................4-39
SENS:ALT:SLEW .................................................................................................................................4-40
SENS:AIRF:QFE .................................................................................................................................4-41
SENS:AIRF:QFF .................................................................................................................................4-42
SENS:AIRF:QNH .................................................................................................................................4-43
SENS:MACH .................................................................................................................................4-44
SENS:MACH:INL .................................................................................................................................4-45

iv K0472 Revision A
SENS:MACH:INL:TIME ............................................................................................................................4-46
SENS:MACH:RANG .................................................................................................................................4-47
SENS:MACH:SLEW .................................................................................................................................4-48
:SENS:PRES .................................................................................................................................4-49
:SENS:PRES:AVER .................................................................................................................................4-50
:SENS:PRES:AVER:RES............................................................................................................................4-51
:SENS:PRES:AVER:TIME..........................................................................................................................4-52
:SENS:PRES:INL .................................................................................................................................4-53
:SENS:PRES:INL:TIME..............................................................................................................................4-54
:SENS:PRES:SLEW .................................................................................................................................4-55
:SENS:PRES:BAR .................................................................................................................................4-56
:SENS:PRES:RANG .................................................................................................................................4-57
:SENS:PRES:RES .................................................................................................................................4-58
:SENS:PRES:CORR:HEAD.......................................................................................................................4-59
:SENS:PRES:CORR:HEAD:STAT............................................................................................................4-60
:SENS:PRES:CORR:HEAD:OFFS...........................................................................................................4-61
:SENS:PRES:CORR:HEAD:OFFS:STAT ................................................................................................4-62
:SENS:PRES:CORR:VOL ..........................................................................................................................4-63
:SENS:PRES:FILT:LPAS:BAND...............................................................................................................4-64
:SENS:PRES:FILT:LPAS:FREQ ................................................................................................................4-65
:SENS:PRES:FILT:LPAS:STAT..................................................................................................................4-66
:SENS:PRES:MAX .................................................................................................................................4-67
:SENS:PRES:MAX:RES .............................................................................................................................4-68
:SENS:PRES:MIN .................................................................................................................................4-69
:SENS:PRES:MIN:RES ..............................................................................................................................4-70
:SENS:PRES:PERC .................................................................................................................................4-71
:SENS:PRES:PERC:SPAN ........................................................................................................................ 4-72
:SENS:PRES:PERC:STAT..........................................................................................................................4-73
SENS:SPE .................................................................................................................................4-74
SENS:SPE:INL .................................................................................................................................4-75
SENS:SPE:INL:TIME .................................................................................................................................4-76
SENS:SPE:RANG .................................................................................................................................4-77
SENS:SPE:SLEW .................................................................................................................................4-78
SOURce .................................................................................................................................4-79
SOUR:ALT .................................................................................................................................4-79
SOUR:MACH:REF .................................................................................................................................4-80
SOUR:MACH:REF:MODE........................................................................................................................4-81
SOUR:MACH:REF:VAL.............................................................................................................................4-82

K0472 Revision A v
SOUR:MACH:LEV:IMM:AMPL...............................................................................................................4-83
:SOUR:PRES:COMP .................................................................................................................................4-84
:SOUR:PRES:EFF .................................................................................................................................4-85
:SOUR:PRES:INL .................................................................................................................................4-86
:SOUR:PRES:INL:TIME.............................................................................................................................4-87
:SOUR:PRES:LEV:IMM:AMPL ................................................................................................................4-88
:SOUR:PRES:LEV:IMM::VENT................................................................................................................4-89
:SOUR:PRES:RANG .................................................................................................................................4-91
:SOUR:PRES:RANG:LOW .......................................................................................................................4-92
:SOUR:PRES:SLEW .................................................................................................................................4-93
:SOUR:PRES:SLEW:MODE.....................................................................................................................4-94
:SOUR:PRES:SLEW:OVER .......................................................................................................................... 4-95
SOUR:MACH:LEV:IMM:AMPL...............................................................................................................4-96
SOUR:MACH:LEV:IMM:AMPL:SLEW..................................................................................................4-97
STATus .................................................................................................................................4-98
:STAT:OPER:COND .................................................................................................................................4-98
:STAT:OPER:ENAB .................................................................................................................................4-99
:STAT:OPER:EVEN .................................................................................................................................4-100
:STAT:OPER:PRES:COND........................................................................................................................4-101
:STAT:OPER:PRES:ENAB.........................................................................................................................4-102
:STAT:OPER:PRES:EVEN .........................................................................................................................4-103
:STAT:PRES .................................................................................................................................4-105
:STAT:QUES:COND .................................................................................................................................4-106
:STAT:QUES:ENAB .................................................................................................................................4-107
:STAT:QUES:EVEN .................................................................................................................................4-108
SYSTem .................................................................................................................................4-109
SYST:COMM:USB .................................................................................................................................4-109
:SYST:ERR .................................................................................................................................4-110
:SYST:DATE .................................................................................................................................4-112
:SYST:SET .................................................................................................................................4-113
:SYST:TIME .................................................................................................................................4-114
:SYST:COMM:SER:CONT:RTS ...............................................................................................................4-115
:SYST:COMM:SER:CONT:XONX ...........................................................................................................4-116
:SYST:COMM:SER:BAUD........................................................................................................................4-117
:SYST:COMM:SER:TYPE:PAR.................................................................................................................4-118
:SYST:COMM:GPIB:SELF:ADDR ........................................................................................................... 4-119
:SYST:AREA .................................................................................................................................4-120
:SYST:PASS:CDIS .................................................................................................................................4-121
:SYST:PASS:CEN .................................................................................................................................4-122

vi K0472 Revision A
:SYST:PASS:CEN:STAT .............................................................................................................................4-123
:SYST:VERS .................................................................................................................................4-124
UNIT .................................................................................................................................4-125
UNIT:ALT .................................................................................................................................4-125
UNIT:CONV .................................................................................................................................4-126
:UNIT:PRES .................................................................................................................................4-127
UNIT:PRES:DEF .................................................................................................................................4-128
:UNIT:SPE .................................................................................................................................4-130
4.2 * Common SCPI commands - three letter commands, prefixed by * ...........................4-131
*CLS .................................................................................................................................4-131
*ESE .................................................................................................................................4-132
*ESR .................................................................................................................................4-133
*IDN? .................................................................................................................................4-134
*OPC .................................................................................................................................4-135
*SRE .................................................................................................................................4-136
*STB? .................................................................................................................................4-137
*TST? .................................................................................................................................4-138
*WAI .................................................................................................................................4-139
4.3 Instrument control commands - three letter commands, prefixed by :......................4-140
:GTL .................................................................................................................................4-140
:LLO .................................................................................................................................4-141
:LOC .................................................................................................................................4-142
:REM .................................................................................................................................4-143
:SRQ .................................................................................................................................4-144
:SRQ:ENAB .................................................................................................................................4-145
:SYN .................................................................................................................................4-146
5 ERRORS .......................................................................................................... 5-1
List of Illustrations
Figure page
Figure 1-1 System Model.....................................................................................................................................1-1
Figure 3-1 Status System ....................................................................................................................................3-2
List of Tables
Table page
3-1 Standard Event Register.............................................................................................................................3-4
3-2 Operation Status Register..........................................................................................................................3-6
3-3 Status Byte Register......................................................................................................................................3-8
5-1 Errors -100 to -199 .......................................................................................................................................5-1
5-2 Errors -200 to -299 .......................................................................................................................................5-2
5-3 Errors -300 to -400 .......................................................................................................................................5-2

K0472 Revision A vii
5-3 Errors +201 to +212......................................................................................................................................5-2
Abbreviations
The following abbreviations are used in this manual; abbreviations are the same in the singular and plural.
Pressure measurement units
The following units are used in this manual
aAbsolute mVmillivolts
ALT Altitude MWP Maximum working pressure
ASCII American Standard Code for Information Interchange No Number
CAS Calibrated airspeed PACE Pressure automated calibration
equipment
e.g. For example PDCR Pressure transducer
Fig. Figure PED Pressure equipment directive
ft Foot PTX Pressure transmitter
g Gauge ROC Rate of climb
GPIB General purpose interface bus RS232 Serial communications standard
IDOS Intelligent digital output sensor (GE product) Rt CAS Rate of Calibrated airspeed
i.e. That is Rt MACH Rate of MACH
IEEE 488 Institute of Electrical and Electronic Engineers standard
488 (for programmable devices with a digital interface) Rx Receive data
kg kilogram SCPI Standard commands for
programmable instruments
kts knots SDS Sales data sheet
m Metre Tx Transmit data
mA milliampere UUT Unit under test
max Maximum +ve Positive
mbar Millibar -ve Negative
min Minute or minimum °C Degrees Celsius
mm millimetre °F Degrees Fahrenheit
ATM
BAR
CMH2O
CMHG
FTH2O
FTH2O4
HPA
INH2O
INH2O4
INH2O60
INHG
KG/CM2
atmosphere
bar
centimetres of water at 20°C
centimetres of mercury
feet of water at 20°C
feet of water at 4°C
hecto Pascals
inches of water at 20°C
inches of water at 4°C
inches of water at 60°F
inches of mercury
kilogrammes per square centimetre
KG/M2
KPA
LB/FT2
MH2O
MHG
MMH2O
MMHG
MPA
PA
PSI
TORR
MBAR
kilogrammes per square metre
kilo Pascals
pounds per square foot
metres of water
metres of mercury
millimetres of water
millimetres of mercury
mega Pascals
Pascals
pounds per square inch
torr
millibar

viii K0472 Revision A
Code Definitions
The following codes are used in this manual.
ABOR Abort LIM Limit
ADDR Address LLO Local lock out
AVER Average LOG Logical
ALT Altitude LPAS Low pass (filter)
AMPL Amplitude MAV Message available in output queue
ATOD Analog to Digital MEAS Measure
BAR Barometer MSS Summary bit after SRQ
BRID Bridge NEGC Negative Calibration
CAL Calibration OFFS Offset
CAT Catalogue OPC Operational condition
CDIS Cdisable (calibration disable) OPER Operation
CEN Cenable (calibration enable) OPT Option
CLS Clear OSB Summary bit from standard operations status register
COMM Communicate OVER Overshoot
COMP Compensate OUTP Output
COND Condition PAR Parity
CONF Configuration PASS Password
CONT Controller PERC Percent
CONV Convert POIN Points
CORR Correction PRES Preset
COUN Count PRES Pressure
DEF Define QUE Queue
DIAG Diagnostic QUES Questionable
DIOD Diode RANG Range
DISP Display REF Reference
EAV Error in error queue RES Resolution
EFF Effort RES RESet
ENAB Enable SAMP Sample
EOI End of input SENS Sense
ERR Error SEPT Set-point
ESB Summary bit from standard event SER Serial
ESE Event status enable SOUR Source
ESR Event status register SPE Speed
EVEN Event SRE Service request enable
FILT Filter SRQ Service request
FREQ Frequency STAR Start
FULL Fullscale STB Status register query
GTL Go to local STAT State
HEAD Head SYST System
IDN Identification TIM Time to set-point
IMM Immediate UNIT Unit of pressure
INL In limit VAL Value
INP Input VALV Valve
INST Instrument VERS Version
ISOL Isolation VOL Volume
LEV Level

PACE Series SCPI Manual
K0472 Revision A 1-1
1INTRODUCTION
1.1 General
The IEEE 488 and RS232 interfaces of the PACE Series provide remote control of the
instrument from a suitable computer or controller. The SCPI protocol enables any instrument
with a SCPI facility to be controlled using the same commands. The PACE Series use the full
SCPI command set and the defined SCPI syntax.
The following sections describe and define each instrument command used by the PACE
Series. The commands for the aeronautical option and the sensor calibration module option
are described and defined in separate sections. Each section contains a quick reference
structure of the relevant commands.
Figure 1-1 System Model
System Model
SCPI starts with a high-level block diagram of the measurement functions of the instrument.
Each functional block is broken down into smaller block diagrams. SCPI contains a hierarchy
of commands called a subsystem that maps directly to the hierarchy of the block diagram.
1.2 Remote/Local Operation
Most commands received over the SCPI interface automatically puts the PACE Series into
remote control mode and disables the front panel touch-screen. Sending the LOC command
returns the PACE Series to local control mode and enables the front panel touch-screen .
Pressure
out
logic
logic
Pressure
in
SOURce
sub-system
UNITs
sub-system
CALibrate
sub-system
INPut
sub-system
SENSe
sub-system
INSTrument
sub-system
OUTPut
sub-system
SYSTem
sub-system
S TATu s
sub-system

1 Description
K0472 Revision A 1-2
intentionally left blank

PACE Series SCPI Manual
K0472 Revision A 2-1
2 COMMAND STRUCTURE
This section describes the structure of the commands and data sent and received by a PACE
Series Controller/Calibrator.
2.1 Notation
All SCPI commands are based on a hierarchical tree structure consisting of key words and
parameters. Associated commands are grouped together under a common node in the
hierachy.
In the command tree the command A is the root command. A tree pointer is used to decode
the SCPI commands. At power-up the pointer goes to the root command.
2.2 Message Terminators
All SCPI commands are terminated by line feed i.e., either <newline> (ASCII character,
decimal 10), EOI for IEEE. After receiving a termination character the tree pointer returns to
the root command.
Colon
A colon moves the current path down one level in the command tree, (e.g., the colon in
SOURCE:PRESSURE specifies PRESSURE the is one level below SOURCE). When the colon is
the first character of the command, it specifies that the next command is a root level
command (e.g., :SOURCE specifies that SOURCE is a root level command).
Semicolon
A semicolon separates two commands in the same message without changing the tree
pointer.
(e.g., with reference to the tree):A:B:E;F;G
This equivalent to sending three messages:
:A:B:E
:A:B:F
:A:B:G
root Level 1 Level 2
AB
C
D
E
F
G
H
J

2 Command Structure
K0472 Revision A 2-2
Commas
If a command requires more than one parameter, separate adjacent parameters by using a
comma. A comma does not affect the tree pointer.
(e.g.) :SYSTEM:TIME 10,25,30
To execute a command the full path to the command must be specified:
(e.g.) :OUTPut:STATe ON
This turns the pressure controller on.
Note:
There must be a space between the command words and the parameter. In the above
example there is a space between :STATe and ON.
SCPI commands are not case sensitive and may have a short form.
(e.g.) :OUTP is the short form of OUTPUT.
Some nodes can be the default node and these key words are optional when programming
the command. The instrument processes the command, with the same effect, with or
without the option node. In this manual [] enclose [default notes].
(e.g.) :SOURce[:PRESsure:][:LEVel][:IMMediate][:AMPlitude] 5.0
can be sent as
:SOURce:PRESsure:LEVel 5.0
or
:SOURce 5.0
This sets the set-point to 5.0

PACE Series SCPI Manual
K0472 Revision A 2-3
2.3 Program Headers
Program headers are keywords that identify a command, instruments accept both upper
and lower case characters in a program header. There are two types of program header,
common command headers and instrument control headers; each header can be a
command or a query.
Common Command and Query Headers
The common command and query program header syntax, specified in IEEE 488.2, are
defined as follows:
Command
*<PROGRAM MNEMONIC>
Query
*<PROGRAM MNEMONIC>?
Instrument Control Command and Query Headers
The instrument control command and query program header syntax controls and extracts
data from the instrument as follows:
Command
:<MNEMONIC>
:<MNEMONIC> <PARAMETER>
Query
:<MNEMONIC>?
Instrument command headers can have a numeric suffix to identify each of several cases of
the same header; the numeric suffix applies to both the long and short forms. All commands
headers without a numeric suffix assume the value 1.
e.g.,
:OUTPut:LOGic1?
is the same as
:OUTPut:LOGic:?
Queries
A query is a program header with an attached question mark character (?). On receiving a
query, the current settings are loaded in the output buffer. A query does not affect the
operation or set-up of the instrument.
When the parameter of a command contains enumerated character data, both long form
and short form are recognised. A query causes the return of data in the short form.
Querying numeric parameters causes the resulting data to be returned in the units selected
by the instrument unless specified otherwise.

2 Command Structure
K0472 Revision A 2-4
2.4 SCPI Data Types
A variety of data types can be sent to the instrument as parameters or sent out from the
instrument as response data.
Decimal Data
All normal decimal expressions are accepted including optional signs, decimal point and
scientific notation.
Note:
This includes floating point data.
The following are valid:
123
45.67
-2.6
4.6e-10
.76
A suffix multiplier can be added to the numeric value.
:SOUR 100 m
would set the programmable output to 0.1 units (100m units).
The multipliers supported are:
Mnemonic Multiplier
A1e-18
G1e+9
K1e+3
M1e-3
T 1e+12
If a real value is sent to the instrument when an integer is expected, it will be rounded to an
integer.
Integer Data
Integer data are whole numbers (containing no decimal places). A query of an integer value
returns numbers containing no decimal places.
Note:
Integer values can be specified in binary, octal or hexadecimal formats using the suffix letters
(upper or lower case) B, Q and H respectively.
e.g., #B1010 binary representation of 10
#Q71 octal representation of 57
#HFA hexadecimal representation of 250
Hexadecimal digits A-F can be in upper or lower case.

PACE Series SCPI Manual
K0472 Revision A 2-5
Enumerated Character Data
Enumerated characters are used for data that has a finite number of values; enumerated
parameters use mnemonics to represent each valid setting.
The mnemonics have long and short forms just like command mnemonics.
Example:
:SOURce:PRESsure:SLEW:MODE MAXimum
selects the maximum rate mode.
A query of an enumerated parameter always returns the short form data in upper case.
Example:
:SOURce:PRESsure:SLEW:MODE?
queries rate mode, reply:
:SOUR:PRES:SLEW:MODE MAX
Boolean Data
Boolean data can only be one of two conditions; the numbers 1 and 0. Boolean can be “on”
or “off”, queries return 1 or 0.
Example:
:OUTPut:STATe 1
A query of boolean data always returns 1 or 0.
String Data
String data can contain any of the ASCII characters. A string must start with a double
"quote" (ASCII 34) or a single `quote` (ASCII 39) and end with the same character.
Note:
Characters in a string in either double "quote" or single `quote` are case sensitive.
Example: 1
:SOURCe[:PRESsure]:RANGe ‘2.00barg’
Example: 2
:SOURCe[:PRESsure]:RANGe “2.00barg”
selects the 2 bar g range.
A query of a string parameter always returns the string in double "quotes".

2 Command Structure
K0472 Revision A 2-6
Intentionally left blank

PACE Series SCPI Manual
K0472 Revision A 3 - 1
3 STATUS SYSTEM
The status reporting system informs the external controller that an event has occurred. This
information is in the form of a service request (SRQ) using IEEE 488 or an SRQ message using
RS232.
The PACE Series uses status reporting as defined in IEEE 488.2 with the implementation of
status registers.
The OPERation status registers have been implemented to comply with the SCPI protocol.
These are registers where the individual bits are summary bits of the status of the
instrument. Since the SCPI protocol does not include pressure instruments, bit 10 of both
these registers are used as a pressure summary bit. This pressure summary bit is expanded
to two, 16 bit registers (Bit 15 is not used and is always zero).
The only bit implemented in the Operation status register is bit 10 (summary of the pressure
operation status).
A summary bit is the final output of a data structure, it is a single bit that shows the status of
one or more related events in the instrument. The basic structure of a summary bit
• Condition register
•Eventregister
• Enable register
• Logical ANDing of the Event and Enable registers
• Summary bit that summarises the result using OR logic
Condition Register
This register shows the current status of the device. The condition register is constantly
updated - the bits in the register are set or reset showing the current condition.
Event Register
The event register shows an event that occurs in the condition register (a condition bit goes
from low to high). This condition change is stored and only reset when the event register is
read or the *CLS command sent.
Enable Register
This register allows the results of the event register to pass through to the next cascaded
register and enables the user to select the event that should generate the final SRQ event.

3 Status System
K0472 Revision A 3 - 2
The status system implemented in the instrument is shown in the following diagram:
Note:
Initial values of registers are 0, with the queues empty.
Key:
C = Condition - variable values
EV = Latched values
EN = Bit mask
Figure 3-1 Status System
logical OR
MAV
ESB
OSB
MSS
MAV
ESB
OSB
Status Byte
EN 8 bitEV
*SRE
STAT:OPER
:ENAB
*STB?
SERIAL POLL
STAT:OPER
:PRES:ENAB 511
Pressure Operations 15 bit
STAT
:OPER
:EVENT?
STAT:OPER
:PRES:ENAB?
Operation Status 16 bit
logical OR
CEV EN
logical OR
C
EVEN
Output Queue
Message
Message
Message
Message
SYST:ERR?
*SRE
Error Queue
Error Message
Error Message
Error Message
Error Message
Error Message
logical OR
QYE
CME
EXE
QYE
CME
EXE
Standard Event
EV EN 8 bit
*ESR? *ESE
MSS
EAV
EAV