SIM984 - Measurement SRS - Free user manual and instructions

USER MANUAL SIM984 SRS

Revision1.13• March11,2013

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Warranty

ThisStanfordResearchSystemsproductiswarrantedagainstdefectsinmaterialsandworkmanshipforaperiodofone(1)yearfromthedateofshipment.

Service

Forwarrantyserviceorrepair, thisproductmustbereturnedtoaStanfordResearchSystems authorizedservicefacility.ContactStanfordResearchSystemsoranauthorizedrepresentative beforereturningthisproductforrepair.

Informationinthisdocumentissubjecttochangewithoutnotice.

Copyright © StanfordResearchSystems, Inc., 2013. Allrightsreserved.

StanfordResearchSystems, Inc.

1290-DReamwoodAvenue

Sunnyvale, CA94089 USA

Phone:[phone]• Fax:[phone]

www.thinkSRS.com• e-mail:[e-mail]

PrintedinU.S.A.Documentnumber9-01691-903

Contents

GeneralInformationiii

Symbols......iv
Notation......v
Specifications......vi

1GettingStarted1-1

1.1 Introduction to the Instrument......1-2
1.2Front-PanelOperation....1-2
1.3SIMInterface....1-4

2RemoteOperation2-1

2.1IndexofCommonCommands....2-2
2.2AlphabeticListofCommands ......2-3
2.3Introduction 2-4
2.4Commands 2-4
2.5StatusModel 2-13

3Circuitry

3.1 CircuitDescriptions ......3-2
3.2SchematicDiagrams....3-3

3-1

GeneralInformation

TheSIM984IsolationAmplifier, part of Stanford Research Systems' Small Instrumentation Modules family, is a wide bandwidth, low noise isolation amplifier for use with analog signals from DC to 1 MHz.

Service

Donotinstallsubstitutepartsorperformanyunauthorizedmodificationstothisinstrument.

TheSIM984isasingle-widemoduledesignedtobeusedinsidethe SIM900Mainframe.Donotturnonthepoweruntilthemoduleis completelyinsertedintothemainframeandlockedinplace.

SymbolsyoumayFindonSRSProducts

Symbol Description
	Alternating current
	Caution - risk of electric shock
	Frame or chassis terminal
	Caution - refer to accompanying documents
	Earth (ground) terminal
	Battery
	Fuse
	On (supply)
	Off (supply)

Notation

WARNING

CAUTION

The following notation will be used throughout this manual.

A warning mean that injury or death is possible if the instructions are not obeyed.

Acautionmeansthatdamagetotheinstrumentorotherequipment is possible.

Typesetting conventions used in this manual are:

• Front-panelbuttonsaresetas[Button].
• Front-panelindicatorsaresetasOverload.
• Remotecommandnamesaresetas*IDN?
• LiteraltextotherthancommandnamesissetasOFF.

Remotecommandexampleswillallbesetinmonospacedfont.In theseexamples,datasentbythehostcomputertotheSIM984areset asstraightteletypefont,whileresponsesreceivedbythehost computerfromtheSIM984aresetasslantedteletypefont.

Specifications

PerformanceCharacteristics

Isolationvoltage±1000V(max)
Leakagecurrent<2μAat1000Vdc
Isolationcapacitance1000pF
IsolationModeRejectionRatio(IMRR)150dBatDC
Maximuminput±10V
Inputimpedance1MΩ
Inputnoise(typ.)15nV/ √Hz@1kHz
Inputoffsetdrift3μV/ °C(typ.)
Outputvoltagerange±10V
Outputcurrent±20mA(max.)
Outputresistance50Ω
Outputoffset±0.1V,adjustable
Outputoffsetdrift1mV/ °C(typ.)
Outputnoise(typ.)80μVrms(100Hzbandwidth)

GeneralCharacteristics

InterfaceSerial(RS-232)throughSIMinterface

Connectorsbananajack(2front)

Weight1.5lbs

Dimensions1.5 " W× 3.6H× 7.0 D

1GettingStarted

Thischaptergivesyouthenecessaryinformationtogetstarted quicklywiththeSIM984IsolationAmplifier.

InThisChapter

1.1 Introduction to the Instrument......1-2

1.1.1Overview....1-2
1.1.2 Power-onState....1-2

1.2Front-PanelOperation....1-2

1.2.1 Inputs....1-2
1.2.2Gain....1-2
1.2.3Bandwidth....1-3
1.2.4Output....1-3

1.3SIMInterface....1-4

1.3.1SIMinterfaceconnector....1-4
1.3.2 Directinterfacing......1-5

1.1 Introduction to the Instrument

TheSIM984IsolationAmplifierisalow-noise, programmablegain amplifierforisolatinganalogsignalsfromDCto1MHz.

1.1.1 Overview

The basic function of the SIM984 istoisolate and (possibly) amplify an analog signal. The input presents a 1MΩ impedance between the red and black bananajacks, but high impedance (floating) between each input jack and chassis ground. A maximum of ±1000V dccan be between neither jack and ground, but the potential between the input jacks must be less than ±10V. The input is DC coupled.

A gain of ×1, ×10, or ×100 can be set from the front panel. The output bandwidth this also adjustable from the front panel, with three choices of high-frequency cut-off: 100Hz, 10kHz, and 1MHz. Finally, the output DC offset can be trimmed using athinscrew driver accessing the "Offset" holeneartheoutputBNC.

1.1.2 Power-onState

TheSIM984storesitsoperationstate(gainandbandwidthconfiguration)innon-volatilememory.Atpower-on,theSIM984willreturntoitspreviousconfigurationafterabriefsystemcheckandinitialization.

1.2 Front-Panel Operation

ThefrontpaneloftheSIM984(seeFigure1.1)providesasimple operatorinterface.

1.2.1 Inputs

TheinputtotheSIM984isthroughtheredandblackbananajacksin thefront-panel"INPUT"block.

WARNING

Thebananajacksareisolatedfromthechassisforusewithinsulated testleads. IftheuserconnectsaBNC-to-Bananaadaptortothe SIM984toallowinputsfromaBNC-terminatedcable,itiscritical thatnodangerousvoltagesbeappliedtothecable,astheexposed shieldoftheinputBNCcouldcreateanelectricalhazard.

1.2.2Gain

User gain settings of ×1, ×10, and ×100, are selected with the left and right[Gain]buttons.

SRS SIM984 Isolation Amplifier INPUT 10 V Max 1 MΩ 1000 V Max GAIN 1 10 100 BANDWIDTH 100 10 1 Hz kHz MHz OUTPUT Offset OVLD

SIM984 ISOLATION AMP OUTPUT S/N ✓SRS MADE IN U.S.A.

Figure1.1:TheSIM984frontandrearpanels.

1.2.3Bandwidth

UserbandwidthsettingsofDC-100Hz,DC-10kHz,andDC-1MHz arewiththeleftandright[Bandwidth]buttons.

1.2.4Output

Theamplified,band-limitedsignalappearsatthe(ground-referenced) BNCconnectorsonthefrontandrearpanels.Eachoutputconnectionisthrougha50Ωresistor.Fornormaloperation,theusershould notneedtoterminatetheoutput.Ifa50Ωterminationisapplied, theoutputsignalwillbedividedinhalf.

If the output signals exceed ±10V, the output overload detection is activated. This is indicated by the OVL D near the top of the "OUTPUT" block on the front panel.

TheSIM984outputoffsetvoltagemaybetrimmedbyadjustingthe

outputoffsetthroughthefront-panelaccessholeinthe"OUTPUT" block.

1.3SIMInterface

The primary connection to the SIM984 Isolation Amplifier is therear-panel DB-15 SIM interface connector. Typically, the SIM984 is mated to a SIM900 Mainframe viathis connection, either through one of the internal Mainframeslots, or theremotecable interface.

ItisalsopossibletooperatetheSIM984directly, without using the SIM900Mainframe. Thissectionprovidesdetailsontheinterface.

CAUTION

TheSIM984hasnointernalprotectionagainstreversepolarity,missing supply,orovervoltageonthepowersupplypins.Misapplicationofpower maycausecircuitdamage.SRSrecommendsusingtheSIM984together withtheSIM900Mainframeformostapplications.

1.3.1 SIMinterfaceconnector

TheDB-15SIMinterfaceconnectorcarriesallthepowerandcommunicationslinestotheinstrument.Theconnectorsignalsarespecified inTable1.1

PinSignalSrc	DestDescription	Direction
1	SIGNAL_GND	MF SIM	Ground reference for signal
2	-STATUS	SIM MF	Status/service request (GND = asserted, +5 V=idle)
3	RTS	MF SIM	HW handshake (not used in SIM984)
4	CTS	SIM MF	HW handshake (not used in SIM984)
5	-REF_10MHZ	MF SIM	10 MHz reference (no connection in SIM984)
6	-5 V	MF SIM	Power supply (no connection in SIM984)
7	-15 V	MF SIM	Power supply
8PSRTN		MF SIM	Powersupplyreturn
9CHASSISGND		Chassisground
10	TXD	MF SIM	Async data (start bit = “0”= +5 V; “1” = GND)
11	RXD	SIM MF	Async data (start bit = “0”= +5 V; “1” = GND)
12	+REF_10MHz	MF SIM	10 MHz reference (no connection in SIM984)
13	+5 V	MF SIM	Power supply
14	+15 V	MF SIM	Power supply
15	+24 V	MF SIM	Power supply

Table1.1:SIMInterfaceConnectorPinAssignments,DB-15

1.3.2 Directinterfacing

TheSIM984isintendedforoperationintheSIM900Mainframe, but usersmaywishtodirectlyinterfacethemoduletotheirownsystems withouttheuseofadditionalhardware.

ThematingconnectorneededisastandardDB-15receptacle,such asAmppart#747909-2(orequivalent).Clean,well-regulatedsupply voltages of ± 15, + 5 and +24 VDC must be provided, following thepin-outspecifiedinTable1.1.Groundmustbeprovidedon pins1and8,withchassisgroundonpin9.The-STATUSsignal maybemonitoredonpin2foralow-goingTTL-compatibleoutput indicatingastatusmessage.

1.3.2.1 Directinterfacecabling

If the user intend stodirectly wire the SIM984 independent of the SIM900 Mainframe, communication is usually possible by directly connecting the appropriate interfacelines from the SIM984DB-15 plug to the RS-232 serial port of a personal computer. ^1 Connect RXD from the SIM984 directly to R Don the PC, TX D directly to TD. In other words, anull-modem styleable is not needed.

TointerfacedirectlytotheDB-9male(DTE)RS-232porttypically foundonpersonalcomputers,acablemustbemadewithafemale DB-15sockettomatewiththeSIM984,andafemaleDB-9socket tomatewiththePC'sserialport. SeparateleadsfromtheDB-15 needtogotothepowersupply,makingwhatissometimesknowas a"hydra"cable.Thepin-connectionsaregiveninTable1.2.

1.3.2.2 Serialsettings

The initial serial port settings at power-on are: 9600 Baud, 8-bits, noparity, 1 stopbit, and no flow control. The serial baud rate and word size are fixed, but the parity may be changed with the PARI command.

DB-15/FtoSIM984Name
DB-9/F 10←→ 3TxD 11←→ 2RxD 5ComputerGround toP/S 7←→ -15VDC 13←→ +5VDC 14←→ +15VDC 15←→ +24VDC 8,9←→ Ground(P/Sreturncurrent) 1←→ SignalGround(separatewiretoGround)
Table1.2:SIM984DirectInterfaceCablePinAssignments

2RemoteOperation

ThischapterdescribesoperatingtheSIM984overtheserialinterface.

InThisChapter

2.1IndexofCommonCommands......2-2
2.2AlphabeticListofCommands....2-3
2.3Introduction....2-4

2.3.1 Power-onconfiguration....2-4
2.3.2Buffers....2-4
2.3.3DeviceClear....2-4

2.4Commands....2-4

2.4.1CommandSyntax....2-5
2.4.2 Notation .....2-6
2.4.3Examples 2-6
2.4.4AmplifierCommands ......2-7
2.4.5StatusCommands....2-7
2.4.6InterfaceCommands....2-9

2.5StatusModel 2-13

2.5.1StatusByte(SB)....2-13
2.5.2ServiceRequestEnable(SRE) .....2-14
2.5.3 Standard Event Status (ESR) ..... 2-15
2.5.4 StandardEventStatusEnable(ESE).....2-15
2.5.5CommunicationErrorStatus(CESR) .....2-15
2.5.6CommunicationErrorStatusEnable(CESE) .2-16

2.1 IndexofCommonCommands

symboldefinition

i,jIntegers

zLiteraltoken

(?)Requiredforqueries;illegalforsetcommands

varparameteralwaysrequired

{var} requiredparameterforsetcommands;illegalforqueries

[var]optionalparameterforbothsetandqueryforms

Amplifier

GAIN(?){i}	2-7Gain
BWTH(?) {i}	2-7	Bandwidth

Status

*STB?[i]	2-7StatusByte
*SRE(?) [i,] {j}	2-7 Service Request Enable
*CLS	2-7ClearStatus
*ESR?[i]	2-8StandardEventStatus
*ESE(?) [i,] {j}	2-8 Standard Event Status Enable
CESR?[i]	2-8CommErrorStatus
CESE(?) [i,]{j}	2-8 Comm Error Status Enable
OVLD?	2-8OverloadCondition
PSTA(?) {z}	2-9 Pulse -STATUS Mode

Interface

*RST	2-9Reset
*IDN?	2-9Identify
*OPC(?)	2-9OperationComplete
CONS(?) {z}	2-10 Console Mode
LEXE?	2-10 ExecutionError
LCME?	2-11 CommandError
PARI(?) {z}	2-11 Parity
TOKN(?) {z}	2-11 Token Mode
TERM(?) {z}	2-12 Response Termination

2.2AlphabeticListofCommands

★

*CLS2-7ClearStatus
*ESE(?) [i,] {j} 2-8 Standard Event Status Enable
*ESR?[i]2-8StandardEventStatus
*IDN?2-9Identify
*OPC(?)2-9OperationComplete
*RST2-9Reset
*SRE(?) [i,] {j} 2-7 Service Request Enable
*STB?[i]2-7StatusByte

B

BWTH(?) {i} 2-7 Bandwidth

C

CESE(?) [i,]{j} 2-8 Comm Error Status Enable CESR?[i] 2-8CommErrorStatus CONS(?) {z} 2-10 Console Mode

G

GAIN(?) {i} 2-7 Gain

L

LCME? 2-11 CommandError LEXE? 2-10 ExecutionError

0

OVLD? 2-8OverloadCondition

P

PARI(?) {z} 2-11 Parity PSTA(?) {z} 2-9 Pulse -STATUS Mode

T

TERM(?) {z} 2-12 Response Termination TOKN(?) {z} 2-11 Token Mode

2.3 Introduction

RemoteoperationoftheSIM984istroughasimplecommandlanguagedocumentedinthischapter.Bothsetandqueryformsof mostcommandsaresupported,allowingtheusercompletecontrol oftheisolationamplifierfromaremotecomputer,eitherthroughthe SIM900MainframeordirectlyviaRS-232(seeSection1.3.2.1).

2.3.1 Power-onconfiguration

Thesettingsfortheremoteinterfaceare9600baudwithnoparity andnoflowcontrol,andlocalechodisabled(CONS0FF).

MostoftheSIM984instrumentsettingsarestoredinnon-volatile memory, andatpower-ontheinstrumentreturnstothestateitwas lastinwhenpowerwasremoved.Exceptionsarenotedinthecommanddescriptions.

Resetvaluesofparametersareshowninboldface.

2.3.2Buffers

Incomingdatafromthehostinterfaceisstoredina32-byteinput buffer. Charactersaccumulateintheinputbufferuntilacommand terminator (either CR or LF ) is received, at which point the messageis parsedandexecuted.QueryresponsesfromtheSIM984are bufferedina32-byteoutputqueue.

If the input buffer overflows, then all data in both the input buffer and the output queue are discarded, and an error is recorded in the CESR and ESR status registers.

2.3.3DeviceClear

TheSIM984hostinterfacecanbeasynchronouslyresettoitspower-on configuration by sending an RS-232-style (break) signal. From theSIM900Mainframe, thisisaccomplished with the SIM900SRST command; if directly interfacing via RS-232, then use a serial break signal. After receiving the Device Clear, the interface is reset and CONS mode is turned 0FF. Note that this only resets the communication interface; the basic function of the SIM984 is left unchanged; toreset the instrument, see *RST.

2.4 Commands

Thissectionprovidessyntaxandoperationaldescriptionsforreomotecommands.

2.4.1 CommandSyntax

The four letter mnemonic (shown in CAPS) in each command sequence specifies the command. Therest of these sequence consists of parameters.

Commandsmaytakeeithersetorqueryform,dependingonwhether the“?”characterfollowsthemnemonic.Setonlycommandsare listed without the “?”, query only commands show the “?” after the mnemonic,andoptionallyquerycommandsaremarkedwitha“(?)”.

Parametersshownin{ }and[]arenotalwaysrequired.Parametersin{ }arerequiredtosetavalue,andareomittedforqueries.Parameters in[]arcoptionalinbothsetandquerycommands.Parameterslisted withoutanysurroundingcharactersarealwaysrequired.

Donotsend()or{ } or[]aspartofthecommand.

Multipleparametersareseparatedbycommas.Multiplecommands maybesentononecommandlinebyseparatingthemwithsemicolons(;)solongastheinputbufferdoesnotoverflow.Commands are terminated by either CR or LF characters. Null commands andwhitespaceareignored. Executionofcommand(s)doesnot beginuntilthecommandterminatorisreceived.

tokens Token parameters (generically shown as z in the command descriptions) can be specified either as a key word or integervalue. Command descriptions list the valid keyword options, with each keyword followed by its corresponding integervalue. Forexample, to set the response termination sequence to CR + LF , the following two commands are equivalent:

TERM CRLF —or— TERM 3

Forqueriesthatreturntokenvalues,thereturnformat(keywordor integer)isspecifiedwiththeTOKNcommand.

2.4.2 Notation

The following tables summarize the notation used in the command descriptions:

symboldefinition

i,jIntegers

zLiteraltoken

(?)Requiredforqueries;illegalforsetcommands

varparameteralwaysrequired

{var} requiredparameterforsetcommands;illegalforqueries

[var]optionalparameterforbothsetandqueryforms

2.4.3Examples

Each command is provided with a simple example illustrating its usage. In these examples, all datasent by the host computerto the SIM984 are set as straight teletype font, while responses received the host computer from the SIM984 are set as slanted teletype font.

Theusageexamplesvarywithrespecttoset/query,optionalparameters,andtokenformats. Theseexamplesarenotexhaustive,butare intended to provide a convenient starting point for user programming.

2.4.4AmplifierCommands

	GainGAIN(?){i}Set (query) input gain {to state i=(0 (×1), 1 (×10), 2 (×100))}.GAIN2
2.4.5StatusCommands	BandwidthBWTH(?){i}Set (query) the signal bandwidth {to state i=(0 (DC-100 Hz), 1 (DC-10kHz),2(DC-1MHz))}.BWTH?Example:1TheStatuscommandsqueryandconfigureregistersassociatedwith statusreportingoftheSIM984.
	StatusByte*STB?[i]ReadstheStatusByteregister[biti].Executionofthe*STB?query(withouttheoptionalbiti)always causes the -STATUS signal to be deasserted. Note that *STB? i will not clear -STATUS, even if bit i is the only bit presently causing the -STATUSsignal.SeealsothePSTAcommand.TheOVLDbitin*STBiscleareduponreading.*STB?Example:1
*SRE(?) [i,] {j}	Service Request EnableSet (query) the Service Request Enable register [bit i] {to j}.Example:*SRE0,1
*CLS	ClearStatus*CLS immediately clears the ESR, CESR, and the OVLD bit in the StatusByte.Example:*CLSStandardEventStatus*ESR?[i]ReadstheStandardEventStatusRegister[biti].Uponexecuting*ESR?,thereturnedbit(s)oftheESRregisterare cleared.*ESR?Example:64
*ESE(?) [i,]{j}	Standard Event Status EnableSet (query) the Standard Event Status Enable Register [bit i] {to j}.*ESE6,1Example:ESE?64
	CommErrorStatusCESR?[i]QueryCommErrorStatusRegister[forbiti].UponexecutingaCESR?query,thereturnedbit(s)oftheCESR registerarecleared.CESR?Example:0
CESE(?) [i},{j}	Comm Error Status EnableSet (query) Comm Error Status Enable Register [for bit i] {to j}CESE?Example:0
OVLD?	OverloadConditionQueryOverloadCondition. IftheSIM984isoverloading,OVLD? returns1;otherwise0.OVLD?Example:0
PSTA(?) {z}	Pulse -STATUS ModeSet (query) the Pulse -STATUS Mode {to z=(OFF 0, ON 1)}.When PSTA ON is set, any new service request will only pulse the -STATUSsignallow(foraminimumof1μs).Thedefaultbehavior istolatch-STATUSlowuntila*STB?queryisreceived.Atpower-on,PSTAassettoOFF.PSTA?Example:OFF

2.4.6InterfaceCommands

	InterfacecommandsprovidegenericcontrolovertheinterfacebetweentheSIM984andthehostcomputer.
	Reset*RSTResettheSIM984todefaultconfiguration.After*RST,thegainissetto×1andthebandwidthtoDC-100Hz.Thisisequivalenttothefollowingcommandsequence:GAIN0;BWTH0
Example:	*RST
*IDN?	IdentifyReadthedeviceidentificationstring.Theidentificationstringisformattedas:StanfordResearchSystems, SIM984,s/n******,ver#.#where*****isthe6-digitserialnumber,and#.#isthefirmware revisionlevel.*IDN?Example:StanfordResearchSystems, SIM984,s/n003075,ver1.02
*OPC(?)	OperationCompleteOperationComplete.SetstheOPCflagintheESRregister.The query form *OPC? writes a 1 in the output queue when complete,butdoesnotaffecttheESRregister.
Example:	*OPC

ConsoleModeCONS(?){z}

Set (query) the Console mode {to z=(OFF 0, ON 1)}.

CONScauseseachcharacterreceivedattheInputBuffertobecopied totheOutputQueue.

Atpower-onandDevice-Clear, CONSissettoOFF.

CONS?Example:

0

ExecutionErrorLEXE?

Querythelastexecutionerrorcode.AqueryofLEXE?alwaysclears theerrorcode,soasubsequentLEXE?willreturn0. Validcodesare:

ValueDefinition

0NoexecutionerrorsincelastLEXE?

1Illegalvalue

2Wrongtoken

3Invalidbit

16Commandnotready

*STB?12;LEXE?;LEXE?Example:

3

0

Theerror(3,"Invalidbit,")isbecause*STB?onlyallowsbit-specific queriesof0-7.ThesecondreadofLEXE?returns0.

	CommandErrorLCME?Querythelastcommanderrorcode.AqueryofLCME?alwaysclearstheerrorcode,soasubsequentLCME?willreturn0. Validcodesare:ValueDefinition
	0NoexecutionerrorsincelastLCME?1Illegalcommand2Undefinedcommand3Illegalquery4Illegalset5Missingparameter(s)6Extraparameter(s)7Nullparameter(s)8Parameterbufferoverflow9Badfloating-point10Badinteger11Badintegertoken12Badtokenvalue13Badhexblock14Unknowntoken*IDNExample:LCME?4Theerror(4,"Illegalset")isduetothemissing"?".
	ParityPARI(?){z}Set (query) parity {to z = (NONE 0, ODD 1, EVEN 2, MARK 3, SPACE 4)}.Afterpower-on,modulesdefaulttoPARINONE.
Example:	PARI EVEN
TOKN(?) {z}	Token ModeSet (query) the Token Query mode {to z=(OFF 0, ON 1)}.If TOKN ON is set, then queries to the SIM module that return tokenswillreturnthetextkeyword;otherwisetheyreturnthedecimal integervalue.Thus, the only possible responses to the TOKN? query are ON and 0.On reset, TOKN is set to OFF.
Example:	TOKN OFF

ResponseTerminationTERM(?){z}

Set (query) the term sequence {to z=(NONE 0, CR 1, LF 2, CRLF 3, LFCR 4) }. The term sequence is appended to all query responses sentbythemodule, and is constructed of ASCII character(s)13(carriagereturn)and10(linefeed). Thetokenmnemonicgivesthe sequenceofcharacters.

Atpower-on, TERMissettoCRLF.

TERM?Example:

3

2.5StatusModel

TheSIM984statusregistersfollowthehierarchicalIEEE-488.2format.AblockdiagramofthestatusregisterarrayisgiveninFigure2.1.

TherearetwocategoriesofregistersintheSIM984statusmodel:

EventRegisters: Theseread-only registers record the occurrence of defined events. Whenthe event occurs, the corresponding bit is set to 1. Upon querying an event register, any set bits within it are cleared. These are sometimes known as "sticky bits," since once set, a bit can only be cleared by reading its value. Event register names end with SR.

Enable Registers: These read/write registers define a bitwise mask for their corresponding event register. If any bit position is set in an event registerwhilethesamebitpositionisalsosetintheenable register,thenthecorrespondingsummarybitmessageisset. Enableregister namesendwithSE.

The Status Byte is the top-level summary of the SIM984 status model. When masked by the Service Request Enable register, a bit set in the StatusBytecausesthe-STATUSsignaltobeassertedontherear-panelSIMinterfaceconnector.

Typically, -STATUS remains asserted(low) until a *STB? query is received, at which time -STATUS is deasserted (raised) ^1 . Afterclearing the -STATUS signal, it will only be re-asserted in response to a

graph TD
    A["Standard Event Status"] --> B["PON: Power On 7"]
    A --> C["URQ: User Request 6"]
    A --> D["CME: Command Error 5"]
    A --> E["EXE: Execution Error 4"]
    A --> F["DDE: Device Error 3"]
    A --> G["QYE: Query Error 2"]
    A --> H["INP: Input Buffer Error 1"]
    A --> I["OPC: Operation Complete 0"]
    A --> J["ESR ESE 7"]
    K["Communication Error Status"] --> L["DCAS: Device Clear 7"]
    K --> M["CTSH: CTS Halted 6"]
    K --> N["RTSH: RTS Halted 5"]
    K --> O["OVR: Input Buffer Overrun 4"]
    K --> P["HWOVRN: Hardware Overrun 3"]
    K --> Q["NOISE: Noise Error 2"]
    K --> R["FRAME: Framing Error 1"]
    K --> S["PARITY: Parity Error 0"]
    T["Status Byte"] --> U["7"]
    T --> V["6"]
    T --> W["5"]
    T --> X["4"]
    T --> Y["3"]
    T --> Z["2"]
    T --> AA["1"]
    T --> AB["0"]
    T --> AC["SB"]
    T --> AD["SRE"]
    AE["-STATUS"] --> AF["7"]
    AE --> AG["X"]
    AE --> AH["ESB"]
    AE --> AI["IDLE"]
    AE --> AJ["undef"]
    AE --> AK["undef"]
    AE --> AL["OVLD"]

Figure 2.1:StatusRegisterModelfortheSIM984.

newstatus-generatingcondition.

WeightBitFlag

10OVLD

21undef(0)

42undef(0)

83undef(0)

164IDLE

325ESB

646MSS

1287CESB

OVLD:OverloadBit.Indicates whether an amplifier overload has occurred.

IDLE:Indicates that the Input Buffer is empty and the command parser is idle. Can be used to help synchronize SIM984 query responses.

ESB:EventStatusBit.Indicateswhetheroneormoreoftheenabled eventsintheStandardEventStatusRegisteristrue.

MSS:MasterSummaryStatus.Indicateswhetheroneormoreof theenabledstatusmessagesintheStatusByteregisteristrue. Notethatwhile-STATUSisreleasedbythe*STB?query,MSS isonlyclearedwhentheunderlyingenabledbitmessage(s) are cleared.

CESB:CommunicationErrorSummaryBit. Indicateswhetheroneor more of the enabled flags in the Communication Error Status Registerhasbecometrue.

Most bits in the Status Byte are not cleared by the *STB? query. These bits are only cleared by reading the underlying event registers, or by clearing the corresponding enable registers. The one exception is the OVLDbit, which itself is an event bit, and so is cleared by the *STB? query.

2.5.2 ServiceRequestEnable(SRE)

EachbitintheSREcorrespondsone-to-onewithabitintheSB register, andactsasa bitwiseANDoftheSBflagstogeneratethe MSSbitintheSBandthe-STATUSsignal.Bit6oftheSREis undefined—settingithasnoeffect, andreadingitalwaysreturns0. Thisregisterissetandqueriedwiththe*SRE(?)command.

Thisregisterisclearedatpower-on.

2.5.3 StandardEventStatus(ESR)

TheStandardEventStatusregisterconsistsof8eventflags. These eventflagsareall"stickybits"thataretbythecorrespondingevent, andclearedonlybyreadingorwiththe*CLScommand.Readinga single bit (with the *ESR? i query) clears only bit i.

WeightBitFlag
10	OPC
21	INP
42	QYE
83	DDE
164	EXE
325	CME
646	URQ
1287	PON

OPC:OperationComplete.Setbythe*OPCcommand.

INP:InputBufferError.Indicatesdatahasbeendiscardedfromthe InputBuffer.

QYE:QueryError.IndicatesdataintheOutputQueuehasbeenlost.

DDE:DeviceDependentError.ThisbitisundefinedintheSIM984.

EXE:ExecutionError. Indicatesanerrorinacommandthat was successfully parsed. Out-of-rangeparametersareanexample. The errorcode can be queried with LEXE?.

CME:CommandError.Indicatesaparser-detectederror. Theerror codecanbequeriedwithLCME?.

URQ:UserRequest.Indicatesafront-panelbuttonwaspressed.

PON:PowerOn.Indicatesthatanoff-to-ontransitionhasoccurred

2.5.4 StandardEventStatusEnable(ESE)

TheESEactsasabitwiseANDwiththeESRregistertoproducethe singlebitESBmessageintheStatusByteRegister(SB).Itcanbeset and queriedwiththe*ESE(?)command.

Thisregisterisclearedatpower-on.

2.5.5 CommunicationErrorStatus(CESR)

TheCommunicationErrorStatusregisterconsistsof8eventflags; eachofwhichissetbythecorrespondingevent,andclearedonlyby readingorwiththe*CLScommand. Readingasinglebit(withthe CESR?iquery)clearsonlybiti.

WeightBitFlag

10PARITY

21FRAME

42NOISE

83HWOVRN

164OVR

325RTSH

646CTSH

1287DCAS\$

PARITY:ParityError.Setbyserialparitymismatchonincomingdata byte.

FRAME:FramingError.Setwhenanincomingserialdatabyteismissing theSTOPbit.

NOISE:NoiseError.Setwhenanincomingserialdatabytedoesnot presentasteadylogiclevelduringeachasynchronousbit-periodwindow.

HWOVRN:HardwareOverrun.Setwhenanincomingserialdatabyteis lost due to internal processor latency. Causes the Input Buffer tobeflushed,andresetsthecommandparser.

OVR: Input Buffer Overrun. Set when the Input Buffer is overrun by incoming data. Cause the Input Buffertobeflushed, and reset the command parser.

RTSH:UndefinedfortheSIM984.

CTSH:UndefinedfortheSIM984.

DCAS:DeviceClear. Indicate the SIM984 received the Device Clear signal (an RS-232 ). Clears the Input Buffer and Output Queue, and resets the command parser.

2.5.6 CommunicationErrorStatusEnable(CESE)

TheCESEactsasabitwiseANDwiththeCESRregistertoproduce thesinglebitCESBmessageintheStatusByteRegister(SB).Itcan besetandqueriedwiththeCESE(?)command.

Thisregister iscleared atpower-on.

3Circuits

ThischapterpresentsabriefdescriptionoftheSIM984circuitdesign.

InThisChapter

3.1 CircuitDescriptions......3-2

3.1.1 Isolatedpower....3-2

3.1.2 Inputamplifier....3-2

3.1.3 Outputcircuitry....3-2

3.1.4Digitalcontrol....3-2

3.2SchematicDiagrams....3-3

3.1 CircuitDescriptions

3.1.1 Isolated power

Page3oftheschematicshowstheisolatedsupplythatpowersthe inputstage.Aspread-spectrumoscillator(U302)providestheAC drivesignalforpoweramplifierU301todrivetheisolatingtransformerT301.ThelargecapacitorC305preventsanyrunawayDC currentfromsaturatingthetransformer,whichcouldbegenerated byoffsetvoltagesatU301.

3.1.2 Inputamplifier

The upper portion of Page2 shows the floating input amplifier. Gain is controlled through latching relays U214 and U215, the control coils of which are earth-referenced.

The(amplified)signalisopticallycoupledthroughU205,U206,U207,andU208.

3.1.3 Outputcircuitry

The(earth-referenced)outputcircuitryincludestheoutputbandwidthcontrol. Thiscircuitryisonthelower portionofPage2of theschematics.TheoverallACgainistrimmedusingVR202atthe factory,andshouldnotrequireuseradjustment.

DCoffsetcanbeadjustedwithVR203,accessedfromthefrontpanel oftheinstrument. Notethattheoffsettrimisreferencedtotheoutput, andcomesafterthegainisapplied.

3.1.4 Digitalcontrol

TheSIM984iscontrolledbymicrocontrollerU107.

Acriticalaspectofthedesignistheclock-stopcircuitryimplemented byU102andU105. AsimpleRC-oscillatorisenabledordisabledat pin1ofU102,whichisdrivenbysynchronizingflip-flopU105Bto ensurethatno"runt"clockpulsesareproducedthatwouldviolate U107'sminimumclockperiods.Fourseparateclock-startingsignals arecombinedbyU106:

• Power-onreset
• Amplifieroverload
• Incomingserialdata
• Front-panelbuttonpress

Thefaststart-timeoftheRC-oscillatorensuresthatincomingserialdatawillbecorrectly decodedbythemicrocontroller'sUART, evenwhentheclockisstartedbytheserialstartbitoftheincoming data.Whenthemicrocontrollerhascompletedallpendingactivity, itdrivestheSTOPsignalhigh(pin71ofU107),effectivelyhaltingits ownprocessorclock.Inthisway,theSIM984guaranteesnodigital clockartifactscanbegeneratedduringquiescentoperation.

3.2SchematicDiagrams

Schematicdiagramsfollowthispage.

Electrical schematic diagram of a power supply circuit with labeled components, ICs, resistors, capacitors, and connections.

ISO
Location Amplicator: KCU Interface
Source: Document Number Pcs
Curtosis: 5 NMR1 C
DLC: 20001		1 of 3

Electrical schematic diagram with multiple circuit components, transistors, capacitors, and signal lines labeled with component names and values.

	6	10	2	3	4	5	6	7	8	9	10
Product use under the only demand conditions

Vcc1306 2 1007 Fus 2 1007 Fus 2 1007 Fus 2 1006 Fus 2 1006 Fus 2 1006 Fus 2 SDD LED-1052 SDD LED-1052 SDD LED-1052 SDD LED-1052 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout=10 LEDout 10

+24V 30V C791 541.26 E901 81.94 C729 .10 ICM2 2.0kV C130V F20P C200 2.0kV C200 1.0kV T821 transistor+2 DSB 35V98 ICM2 2.0kV GND-SC E029 EA099 C801 1.11.15 R311 1.20 C904 1.51.015 GVD-SC -12V 150 μΩ +24V 30V C791 541.26 E901 81.94 C729 .10 ICM2 2.0kV C130V F20P C200 2.0kV C200 1.0kV T821 transistor+2 DSB 35V88 ICM2 2.0kV GND-SC E029 EA099 C801 1.11.15 R311 1.20 C904 1.51.015 GVD-SC

IE
Location Amplifier: Front Plate & Power Supply
Source: Current Nomenclator
Curtosis: SN/401°C
DOL: 20001	3 or 3