Druck PACE1000, PACE5000, PACE6000 Operating Manual

Pressure measurement for research & industry

Druck Limited

Fir Tree Lane

Groby

Leicester LE6 0FH

England

Tel: [phone]

PACE Series

Standard Commands for

Programmable Instruments

Communications

Manual

K0472

© Druck Limited 2009

This document is the property of Druck Limited and may not, either in part or whole, be copied or otherwise reproduced, communicated in any way to third parties, nor stored in any data processing system, without the express written authority of Druck Limited.

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K0472 Issue No. 1

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GE

Sensing & Inspection Technologies

PACE

Pressure Automated Calibration Equipment

SCPI Remote Communications Manual - K0472

g

Trademarks

All product names are trademarks of their respective company.

© The General Electric Company all rights reserved.

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)

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i

	Table of Contents
Preliminary pages
Introduction .................................................................................................................................		i
Safety .................................................................................................................................		i
Table of contents (this table)..........................................................................................................................		ii
List of Illustrations .................................................................................................................................		v
List of Tables .................................................................................................................................		v
Abbreviations .................................................................................................................................		vi
Pressure measurement units.........................................................................................................................		vi
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:VAL .................................................................................................................................	4-5
	:CAL:ZERO:VALV .................................................................................................................................	4-6
	:CAL:ZERO:VALV:STAT.............................................................................................................................	4-7
	:CAL:ZERO:AUTO .................................................................................................................................	4-8
	INPut .................................................................................................................................	4-9
	INP:LOG .................................................................................................................................	4-9
	INSTrument .................................................................................................................................	4-10

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Section	page
:INST:CAT .................................................................................................................................	4-10
:INST:CAT:ALL .................................................................................................................................	4-11
:INST:LIM .................................................................................................................................	4-12
:INST:SENS:CALD .................................................................................................................................	4-13
:INST:SENS:FULL .................................................................................................................................	4-14
:INST:SN .................................................................................................................................	4-15
:INST:VERS .................................................................................................................................	4-16
OUTPut .................................................................................................................................	4-17
:OUTP:STAT .................................................................................................................................	4-17
:OUTP:LOG .................................................................................................................................	4-18
SENSe	4-19
:SENS:PRES .................................................................................................................................	4-19
:SENS:PRES:INL .................................................................................................................................	4-20
:SENS:PRES:SLEW .................................................................................................................................	4-21
:SENS:PRES:BAR .................................................................................................................................	4-22
:SENS:PRES:RANG .................................................................................................................................	4-23
:SENS:PRES:RES .................................................................................................................................	4-24
:SENS:PRES:CORR:HEAD.......................................................................................................................	4-25
:SENS:PRES:CORR:HEAD:STAT............................................................................................................	4-26
:SENS:PRES:CORR:HEAD:OFFS...........................................................................................................	4-27
:SENS:PRES:CORR:HEAD:OFFS:STAT ................................................................................................	4-28
:SENS:PRES:CORR:VOL ..........................................................................................................................	4-29
:SENS:PRES:FILT .................................................................................................................................	4-30
:SENS:FILT:LPAS:BAND...........................................................................................................................	4-31
:SENS:FILT:LPAS:FREQ............................................................................................................................	4-32
:SENS:FILT:LPAS:STAT .............................................................................................................................	4-33
SOURce .................................................................................................................................	4-34
:SOUR:PRES:COMP .................................................................................................................................	4-34
:SOUR:PRES:EFF .................................................................................................................................	4-35
:SOUR:PRES:INL .................................................................................................................................	4-36
:SOUR:PRES:INL:TIME.............................................................................................................................	4-37
:SOUR:PRES:LEV:IMM:AMPL ................................................................................................................	4-38
:SOUR:PRES:LEV:IMM::VENT................................................................................................................	4-39
:SOUR:PRES:RANG .................................................................................................................................	4-41
:SOUR:PRES:SLEW .................................................................................................................................	4-42
:SOUR:PRES:SLEW:MODE.....................................................................................................................	4-43
:SOUR:PRES:SLEW:OVER	4-44

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Section		page
	STATus .................................................................................................................................	4-45
	:STAT:OPER:COND .................................................................................................................................	4-45
	:STAT:OPER:ENAB .................................................................................................................................	4-46
	:STAT:OPER:EVEN .................................................................................................................................	4-47
	:STAT:OPER:PRES:COND........................................................................................................................	4-48
	:STAT:OPER:PRES:ENAB.........................................................................................................................	4-49
	:STAT:OPER:PRES:EVEN .........................................................................................................................	4-50
	SYSTem .................................................................................................................................	4-51
	:SYST:ERR .................................................................................................................................	4-51
	:SYST:DATE .................................................................................................................................	4-53
	:SYST:SET .................................................................................................................................	4-54
	:SYST:TIME .................................................................................................................................	4-55
	:SYST:COMM:SER:CONT ........................................................................................................................	4-56
	:SYST:COMM:SER:BAUD ........................................................................................................................	4-57
	:SYST:COMM:SER:TYPE:PAR.................................................................................................................	4-58
	:SYST:COMM:GPIB:SELF:ADDR ...........................................................................................................	4-59
	:SYST:AREA .................................................................................................................................	4-60
	:SYST:PASS:CDIS .................................................................................................................................	4-61
	:SYST:PASS:CEN .................................................................................................................................	4-62
	:SYST:PASS:CEN:STAT .............................................................................................................................	4-63
	:SYST:VERS .................................................................................................................................	4-64
	UNIT .................................................................................................................................	4-65
	:UNIT:PRES .................................................................................................................................	4-65
	UNIT:PRES:DEF .................................................................................................................................	4-66
4.2 * Common SCPI commands - three letter commands, prefixed by * ...........................		4-68
	*CLS .................................................................................................................................	4-68
	*ESE .................................................................................................................................	4-69
	*ESR .................................................................................................................................	4-70
	*IDN? .................................................................................................................................	4-71
	*SRE .................................................................................................................................	4-72
	*STB? .................................................................................................................................	4-73
	Instrument control commands - three letter commands, prefixed by :. .....................	4-74
	:GTL .................................................................................................................................	4-74
	:LOC .................................................................................................................................	4-75
5	ERRORS ..........................................................................................................	5-1

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Figure			page
Figure 1-1		System Model..............................................................................................................................	1-1
Figure 2-1 General Command Syntax ...................................................................................................			2-1
Figure 2-2		Command Syntax .....................................................................................................................	2-2
Figure 2-3		Response Syntax .......................................................................................................................	2-3
Figure 4-1		Command and Query Summary........................................................................................	4-2
Table			page
3-1	Standard Event Register .....................................................................................................................		3-12
3-2	Operation Status Register..................................................................................................................		3-14
3-3	Status Byte Register..............................................................................................................................		3-16
5-1	Errors -100 to -199 ................................................................................................................................		5-1
5-2	Errors -200 to -299 ................................................................................................................................		5-2
5-3	Errors -300 to -400 ................................................................................................................................		5-2
5-3 Errors +201 to +212 ..............................................................................................................................			5-2

The following abbreviations are used in this manual; abbreviations are the same in the singular and plural.

a	Absolute
ASCII	American Standard Code for Information Interchange
e.g.	For example
Fig.	Figure
ft	Foot
g	Gauge
GPIB	General purpose interface bus
i.e.	That is
IEEE 488	Institute of Electrical and Electronic Engineers standard 488
	(for programmable devices with a digital interface)
m	Metre
max	Maximum
mbar	Millibar
min	Minute or minimum
No.	Number
RS232	Serial communications standard
Rx	Receive data
SCPI	Standard commands for programmable instruments
Tx	Transmit data
+ve	Positive
-ve	Negative
°C	Degrees Celsius
°F	Degrees Fahrenheit

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The following units are used in this manual

ATM	atmosphere
BAR	bar
CMH2O	centimetres of water at 20°C
CMHG	centimetres of mercury
FTH2O	feet of water at 20°C
FTH2O4	feet of water at 4°C
HPA	hecto Pascals
INH2O	inches of water at 20°C
INH2O4	inches of water at 4°C
INH2O60	inches of water at 60°F
INHG	inches of mercury
KG/CM2	kilogrammes per square centimetre
KG/M2	kilogrammes per square metre
KPA	kilo Pascals
LB/FT2	pounds per square foot
MH2O	metres of water
MHG	metres of mercury
MMH2O	millimetres of water
MMHG	millimetres of mercury
MPA	mega Pascals
PA	Pascals
PSI	pounds per square inch
TORR	torr
MBAR	millibar

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PACE Series SCPI Manual

1 INTRODUCTION

1.1General

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.

logic	INPut		CALibrate			SYSTem
	sub-system		sub-system			sub-system

Pressure		SENSe		UNITs		STATus
in
		sub-system		sub-system		sub-system
Pressure
out		OUTPut		SOURce		INSTrument
logic		sub-system		sub-system		sub-system
			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.

1.2Remote/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 .

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1 Description

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PACE Series SCPI Manual

2COMMAND STRUCTURE

This section describes the structure of the commands and data sent and received by a PACE Series Controller/Calibrator.

2.1Notation

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.

root				Level 1					Level 2
A				B					E
									F
									G
				C					H
				D					J

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.

2.2Message 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

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2 Command Structure

Commas

If a command requires more than one parameter, separate adjacent parameters by using a comma. A commas 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. In this manual, upper case letter identify the 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

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PACE Series SCPI Manual

2.3Program 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.

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2 Command Structure

2.4SCPI 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
A	1e-18
G	1e+9
K	1e+3
M	1e-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.

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PACE Series SCPI Manual

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:

MAX

Boolean Data

Boolean data can only be one of two conditions; the numbers 1 and 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:

:SOURCe[:PRESsure]:RANGe ‘2BARG’

or

:SOURCe[:PRESsure]:RANGe “2BARG”

selects the 2 bar g range.

A query of a string parameter always returns the string in double "quotes".

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2 Command Structure

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PACE Series SCPI Manual

3STATUS 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

•Event register

•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.

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3 Status System

The status system implemented in the instrument is shown in the following diagram:

Note:

Initial values of registers are 0, with the queues empty.

Error Queue

Output Queue

Error Message

Message

Error Message

Message

Error Message

Message

Error Message

Message

Error Message

SYST:ERR?

*SRE

Standard Event
EV	EN 8 bit
QYE	QYE
		OR
EXE	EXE	logical
CME	CME
*ESR?	*ESE
Operation Status 16 bit

	Status Byte
	EV	EN 8 bit
	EAV	EAV
	MAV	MAV
	ESB	ESB
OR	MSS	MSS
logical	OSB	OSB
	*STB?	*SRE

logical OR

SERIAL POLL

C	EV	EN
	STAT	STAT:OPER
	:OPER	:ENAB
	:EVENT?

logical OR

Pressure Operations 15 bit

STAT:OPER :PRES:ENAB 511

		EN	EV	C
			STAT:OPER
			:PRES:ENAB?
Key:
C	=	Condition - variable values
EV	=	Latched values
EN	=	Bit mask
		Figure 3-1 Status System

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PACE Series SCPI Manual

3.1Output queue

The output queue is a text readable data queue that is read through the IEEE 488 talk command. The queue is cleared by reading all elements in it or by the *CLS command.

Every time a query has been successfully completed, the response, in a text readable format is placed at the end of the output queue. If the MAV bit in the "Status Byte" was previously cleared it will be set. The output queue can contain up to 256 characters. If there is not enough space in the output queue for a new message, the error -350, "Queue overflow" will be placed into the error queue and the most recent output message will be lost.

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3Status System

3.2Standard event group

The standard event group are 8 bit registers that are read by the IEEE 488 standard commands. The event register is cleared by reading it; the event and enable registers are cleared by the *CLS command.

Bits within the standard event condition register are set by system errors and events. In addition to setting the status bits, a text message will be placed in the error queue. The ESB bit in the status byte sets if the associated bit in the event enable register is set. The enable register may be set through the *ESE command so that selected standard events cause the ESB bit to be set. The system events that set each bit are as follows:

Bit	Name	Description	Meaning/data
0	OPC	Not used	Reserved currently returns 0
1	RQC	Not used	Reserved currently returns 0
2	QYE	-400 to -499	Query errors
3	DDE	Not used	Reserved currently returns 0
4	EXE	-200 to -299	Execution errors
5	CME	-100 to -199	Command errors
6	URQ	Not used	Reserved currently returns 0
7	PON	Not used	Reserved currently returns 0

Table 3-1 Standard Event Register

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PACE Series SCPI Manual

3.3Operation status group

The operation status group are 16 bit registers that are read by the STAT:OPER commands. The event register is cleared by reading it; the event and enable registers are cleared by the *CLS command.

When a standard operation condition occurs an appropriate bit is set in the condition register (this clears when the condition no longer exists). The bit is then latched in the event register. If the associated bit in the enable register is set, the OPR bit in the status byte sets. The enable register may be set through the STAT:OPER:ENAB command so that only selected standard operation events cause the OPR bit to set.

Problems can occur with some IEEE 488 controllers reading 16 bit unsigned numbers. All registers in this group do not use bit 15. The enable bit cannot be set and when read returns 0. The condition register is defined as follows:

Vent complete

This signal occurs when the controller has been requested to vent and the vent has completed or timed out.

Range change complete

This signal occurs when the controller has been requested to perform a range change and the range change is complete.

In-Limits reached

This signal is set every time the controlled pressure is within the specified limits. The signal is only generated if the pressure has been within limits for a user defined wait time period.

Zero complete

This signal is generated when a manual or timed zero is complete. If the zero times out then this signal is also generated.

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3 Status System

Bit	Data	Bit	Data
(1)	(2)	(3)	(4)
0	Vent complete	1	Range change complete
2	In-limits reached	3	Zero complete
4	Auto-zero started	5	Fill time, timed-out
6	Reserved - returns 0	7	Reserved - returns 0
8	Switch contacts changed state	9	Reserved - returns 0
10	Reserved - returns 0	11	Reserved - returns 0
12	Reserved - returns 0	13	Reserved - returns 0
14	Reserved - returns 0	15	Reserved - returns 0

Table 3-2 Operation Status Register

Auto zero started

When the controller is in the auto zero mode this signal indicates that the auto zero process has started. Thezero complete signal indicates that the zero process has finished.

Fill timed out

If a set-point has been requested and the set-point cannot be achieved within the fill timeout time, the fill timed out signal is generated.

Switch contacts changed state

Every time the switch contacts used for performing a switch test change state this bit is set.

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PACE Series SCPI Manual

3.4Status Byte group

The status byte group are 8 bit registers that are read by the IEEE 488 standard commands. The event register is cleared by reading it; the event and enable registers are cleared by the *CLS command.

*STB? *SRE?

Error queue

Question data

Output queue

Standard event

Standard operation

EAV

QUE

MAV

ESB

MSS

OSB

Event

EAV

QUE

MAV

ESB

MSS

OSB

Enable

logical OR

SERIAL POLL

Bits within the status byte are a summary of other data structures in the status system. These bits will become set if other parts of the status system indicates that they should do so (i.e., a message in the output queue or error queue or, a condition and enable set in a register pair).

If the associated bit in the status enable register is set, a serial poll is generated and bit 6 is set. The enable register may be set through the *SRE command so that only selected status bits cause a serial poll.

Note: Bit 6 of the enable register is always set to 0.

There are some small differences between * STB? and serial polling. Either method can be used to read the state of bits 0-5 and bit 7. The reading method is different for bit 6 when using *STB? and serial poll. In general, use serial polling inside interrupt service routines, not *STB?

Bit 2 - EAV sets when there is an error in the error queue. The :SYST:ERR? command has to be sent to retrieve the error. The error queue buffers a maximum of five errors. When no more errors are available the message “No Error” is returned.

Bit 4 - MAV sets when there is a message available in the output queue.

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3 Status System

Bit 5 - ESB sets when a standard event has occurred in the Standard Event Register.

Bit 6 - MSS sets when an SRQ is generated - SRQ sets when both the Status byte and the Service Request Enable register are at logic 1 (AND function).

RS232 Specific

A service request (SRQ) produces the message::SRQ <value>

where:

<value> = the contents of the status summary byte.

The status system data structure sets each bit as follows:

Bit	Name	Description
0	-	Reserved currently returns 0
1	-	Reserved currently returns 0
2	EAV	Error in errror queque
3	-	Reserved currently returns 0
4	MAV	Messages available in output queque
5	ESB	Summary bit from standard event
6	MSS	Summary bit after service request - SRQ
7	OSB	Summary bit from standard operations status

Table 3-3 Status Byte Register

Example commands using the Status Byte and Status Byte Enable registers:

*SRE 16 Generate an SRQ interrupt when messages are available. *SRE? Find out what events are enabled to generate SRQ interrupts. *STB? Read and clear the Status Byte Enable register.

IEEE 488 Specific

Bit 7 - OSB sets when the pressure operations register bit 10 changes state. The operations register is a 16 bit register only using bit 10. This bit is a summary of the pressure operations register.

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PACE Series SCPI Manual

Status reporting register structure

To set-up the status reporting system.

1All status registers should be cleared by the command:

*CLS

2The Pressure Operations Event register has to be set to enable the Pressure Operations Condition Register to send all the events to be reported; use the command:

:STAT:OPER:PRES:ENAB 511

The enabled events may also be read by the query: :STAT:OPER:PRES:ENAB?

3The Operation Status Event register must then be enabled to read bit 10 by the command:

:STAT:OPER:ENAB 1024

The enabled events may also be read by the query: :STAT:OPER:ENAB?

4The status request to enable the SRQ must then be set.

To enable only the Operation Status register (OSB) send the command: *SRE 128

To enable the Operation Status register (OSB) and the Error Queue (EAV) send the command:

*SRE 132

This register may also be read by the query:

*SRE?

An event occurring generates an SRQ, the Status Byte should be queried to find the source of the event.

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If bit 2 of the Status Byte Register is set the error queue can be read by the query:

:SYST:ERR?

Keep issuing this query until there are no more errors in the error queue. At this point, bit 2 of the Status Byte Register clears.

If bit 7 of the Status Byte Register is set the Pressure Operations event register can be read by the query:

:STAT:OPER:PRES?

returning the bits of events that have occurred. Reading this register clears it and the associated status bit (bit 7).

At any time the instantaneous status of the pressure system can be read by the query:

:STAT:OPER:PRES:COND?

3.5Instrument Errors

Any instrument error that occurs, either programming errors or execution errors, is stored in an error queue which is separate from the main output queue. The errors can be read by issuing the following command query:

:SYST:ERR?

The error queue can hold up to five errors. Each time the error queue is queried the instrument responds with the next stored error in the queue. The response consists of an error number followed by a string describing the error. When the error queue is empty the instrument responds with:

0,”No error”

Querying the error queue clears the storage location in the error buffer. If more than five errors occur, before being queried, the ‘Queue overflow;Error queue overflow’ message is placed into the error queue. All subsequent errors are lost until the error queue is cleared.

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