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User Manual PXA125

Programming Reference 4-5

OpenInstruemnt

Purpose

Initiates communications with one of the instruments found using the function FindInstrument()

C Syntax

OpenInstrument (int hInstr)

Resource Classes

PXI, PCI

Parameters

Name

Description

hInstr

Instrument handle number. Must be out of a range of instruments that were found in the PXI baskets.
The numbers start at 0 (for first device) to n-1. This value is extracted using the TEComm.dll function
FindInstrument()

Return Values

Completion Codes

Description

PCI_SUCCESS

Function executed without errors

PCI_INS_ALREADY_OPEN

Trying to establish new communication link while instrument has already been connected.

Содержание PXA125

Страница 1: ...RARY WAVEFORM GENERATOR Publication No 010520 PUBLICATION DATE June 2002 REVISION 1 1 Copyright 2002 by LeCroy All rights reserved This book or parts thereof may not be reproduced in any form without written permission of the publisher ...

Страница 2: ...users of its product and to any other person or persons for special or consequential damages of any kind and from any cause whatsoever arising out of or in any way connected with the manufacture sale handling repair maintenance replacement or use of said products Representations and warranties made by any person including dealers and representatives of LeCroy which are inconsistent or in conflict ...

Страница 3: ...mplitude 1 6 Trigger Modes 1 6 Arbitrary Waveforms 1 6 Memory Segmentation 1 7 Remote Control 1 7 Frequency Agility 1 7 Multi instrument Synchronization 1 7 Supplied Accessories 1 8 Specifications 1 8 Functional Description 1 8 Front Panel Connectors 1 8 Output 1 8 SYNC output 1 8 TRIG FSK IN 1 8 SINE OUT 1 9 REF IN 1 9 Operating Modes 1 9 Continuous Mode 1 9 Triggered Mode 1 10 Gated mode 1 10 Bu...

Страница 4: ...rements 2 2 Grounding Requirements 2 2 Calibration 2 3 Abnormal Conditions 2 3 Cleaning 2 3 Long Term Storage or Repackaging for Shipment 2 3 Preparation for Use 2 4 Removing the Instrument From the Bag 2 4 Installation 2 4 Installing instrument Drivers 2 4 Minimum System Requirements 2 5 Windows Software installation 2 5 Windows 95 98 ME Device Driver installation 2 5 Windows 2000 XP Device Drive...

Страница 5: ... in This Manual 3 2 The Opening Screen 3 3 ArbConnection Features 3 6 The Control Panels 3 6 The Main Panel 3 8 Waveforms 3 9 Operating modes 3 9 SYNC Output 3 9 TTLTrig Output 3 9 Output 3 10 The Standard Waveforms Panel 3 10 Parameters 3 10 Frequency 3 10 10 MHz Ref 3 11 Waveforms 3 12 The Arbitrary Sequence Panel 3 13 Parameters 3 13 Sample Clock 3 14 10 MHz Ref 3 14 Sequence Advance 3 15 Using...

Страница 6: ...itor 3 28 Communication 3 28 System Commands 3 29 Command Editor 3 30 The Waveform Composer 3 30 The Commands Bar 3 30 File Commands 3 31 Edit Commands 3 32 View Commands 3 34 Wave Commands 3 35 System Commands 3 37 The Toolbars 3 37 The Waveform Screen 3 40 The FM Composer 3 42 The Commands Bar 3 42 File Commands 3 43 Edit Commands 3 44 Wave Commands 3 46 Generating Waveforms Using the Equation E...

Страница 7: ...trument 4 2 Openinstrument 4 4 OpenAllInstrument 4 6 CloseInstrument 4 8 GetInstrumentAttribute 4 10 GetStateMessage 4 13 The TE5200drv dll Functions 4 14 SendCommand 4 14 SendBlock 4 17 Introduction to SCPI 4 21 Command Format 4 21 Command Separator 4 22 The MIN and MAX Parameters 4 22 Querying parameter Setting 4 22 Query Response Format 4 22 SCPI Command Terminator 4 23 IEEE 488 2 Common Comman...

Страница 8: ... deviation 4 36 FM FUNCtion MODE FIXed USER 4 36 FM FUNCtion SHAPe SINusoid TRIangle SQUare RAMP 4 37 FM FREQuency FM_freq 4 37 FM FREQuency RASTer FM_sclk 4 37 FM TRIGger MODE CONTinuous TRIGered GATEd 4 38 FM TRIGger SLOPe POSitive NEGative 4 38 FREQuency freq MINimum MAXimum 4 38 FREQuency RASTer sclk MINimum MAXimum 4 39 FREQuency RASTer SOURce EXTernal INTernal 4 39 FSK FREQuency RASTer FM_sc...

Страница 9: ...tion TRAiling fall 4 47 RAMP DELay delay 4 47 RAMP TRANsition rise 4 48 RAMP TRANsition TRAiling fall 4 48 SINC NCYCleN_cycles 4 48 GAUSsian EXPonent exp 4 49 EXPonential EXPonent exp 4 49 DC _amplitude 4 49 OUTPut Subsystem 4 50 OUTPut OFF ON 0 1 4 50 OUTPut FILTer NONE 25M 50M ALL 4 50 OUTPut SYNC OFF ON 0 1 4 51 OUTPut SYNC SOURce BIT LCOMplete 4 51 OUTPut SYNC POSition position 4 51 OUTPut SYN...

Страница 10: ...1 TRIGger TIMer interval 4 62 TRIGger IMMediate 4 62 TRG 4 62 TRACe Subsystem 4 63 Arbitrary Waveforms 4 63 Arbitrary Memory Management 4 64 Downloading Arbitrary Waveforms 4 64 TRACe DEFine segment_number length 4 65 TRACe DELete segment_number 4 65 TRACe DELete ALL 4 65 TRACe SELect segment_number 4 66 Sequenced Waveforms 4 66 SEQuence ADVance AUTOmatic STEP SINGle MIXed 4 67 SEQuence ADVance SO...

Страница 11: ... Wave Composer 1 5 Figure 1 4 ArbConnection FM Composer 1 5 Figure 1 5a Segment 1 Sin x x Waveform 1 13 Figure 1 5b Segment 2 Sin Waveform 1 13 Figure 1 5c Segment 3 Pulse Waveform 1 14 Figure 1 5d Sequenced Waveforms 1 14 Figure 2 1 Add New Hardware Wizard 2 6 Figure 2 2 Search for PXA125 Driver 2 7 Figure 2 3 Specify PXA125 Driver Location 2 8 Figure 2 4 Specify Subfolder for Your Instrument 2 9...

Страница 12: ...rbDetector Icon Options 2 25 Figure 2 27 The ArbDetector Dialog Box 2 25 Figure 2 28 The Settings Tab 2 27 Figure 2 29 Editing Chassis Number and Slot Location 2 27 Figure 2 30 Communicating with your Instrument 2 29 Figure 3 1 The Opening Screen 3 3 Figure 3 2 ArbConnection s Toolbars 3 5 Figure 3 3 The Main Panel 3 8 Figure 3 4 The Standard Waveforms Panel 3 12 Figure 3 5 The Arbitrary Sequence ...

Страница 13: ...re 3 23 The Equation Editor Dialog Box 3 48 Figure 3 24 Using the Equation Sample to Combine Two Waveforms 3 52 Figure 3 25 Using the Equation Editor to Modulate Sine Waveforms 3 53 Figure 3 26 Using the Equation Editor to Add Second Harmonic Distortion 3 54 Figure 3 27 Using the Equation Editor to Generate Exponentially Decaying Sinewave 3 55 Figure 3 28 Using the Equation Editor to Build Amplitu...

Страница 14: ...User Manual PXA125 xiv This page intentionally left blank ...

Страница 15: ...he PXA125 and for generating editing and downloading waveforms from a remote computer The following highlights the PXA125 and ArbConnection features Conventions Used in this Manual The following conventions may appear in this manual NOTE A Note contains information relating to the use of this product CAUTION A Caution contains information that should be followed to avoid personal damage to the ins...

Страница 16: ...gits frequency setting limited by 1 µS s 14 bit vertical resolution 2 Meg memory depth Ultra fast waveform downloads 1 ppm clock stability Extremely low phase noise carrier Frequency agility FSK ramped FSK sweep FM Trigger start phase control and breakpoints Built in sequence generator Multiple instrument synchronization with tight phase control ...

Страница 17: ...ckage Instrument control panel Waveform composer and FM signal composer Detailed virtual front panels control all PXA125 functions and modes Wave composer generates edits and downloads complex waveforms FM wave composer generates and downloads complex modulating signals Automatic detection of active instruments Equation editor generates waveforms from equations SCPI command and response editor sim...

Страница 18: ...User Manual PXA125 1 4 Portrayal Translates waveform coordinates from ASCII and other formats Simplifies generation of complex sequences Figure 1 2 ArbConnection Control Panels ...

Страница 19: ...User Manual PXA125 Portrayal 1 5 Figure 1 3 ArbConnection Wave Composer Figure 1 4 ArbConnection FM Wave Composer ...

Страница 20: ...offset amplitude ranges before you apply offset to your signal Trigger Modes Besides its normal continuous mode the PXA125 responds to a variety of trigger sources The output waveform may be gated triggered or generate a counted burst of waveforms A built in trigger generator having a programmable period can be used as a replacement of an external trigger source The internal trigger generator can ...

Страница 21: ...nt chapters Frequency Agility The instrument generates its sample clock from a DDS circuit direct digital synthesis The DDS circuit enables frequency agility through the complete frequency range of the PXA125 Having such an enormous range opens the door for a wide range of applications such as wide band sweep FSK and frequency modulation The PXA125 can generate FSK Ramped FSK and Linear or Logarit...

Страница 22: ... MHz user arbitrary and sequenced waveforms with sampling clock to 125 MS s Output impedance is 50Ω that is the cable connected to this output should be terminated with 50Ω load Amplitude accuracy is calibrated when connected to a 50Ω load The amplitude is doubled when the output impedance is above 1 MΩ SYNC Output The SYNC output generates a single TTL pulse for synchronizing other instruments i ...

Страница 23: ...g mode of the PXA125 The frequency of the sine output is programmed using the sample clock parameter Frequency agility and modulation affect this output directly The sine waveform output is programmed to 125 MHz so it may serve as an additional output to those available on the front panel REF IN This SMB connector accepts 10 MHz TTL level reference signal The external reference input is available ...

Страница 24: ...cuits cause small delay known as system delay System delay cannot be eliminated completely and must be considered when applying a trigger signal It defines how long it will take from a valid trigger edge to the moment that the output reacts Gated Mode In gated mode the PXA125 circuits are armed to generate output waveforms as long as a gating signal is present Unlike the triggered mode the gated m...

Страница 25: ... and waveform length Ramped FSK Ramped FSK is the same as the FSK function except the output frequency is ramped instead of switched to the shift frequency Ramp time is programmable with 3 digits from 100 µs to 1 second FM The FM function modulates the PXA125 sample clock frequency You can frequency modulate the output either with built in waveforms or download complex waveforms to the modulation ...

Страница 26: ... noise and dc There are some parameters associated with each waveform which modify the shape of the waveform to better suit your needs For example different start phase for the sine waveform can be programmed for each channel to create phase offsets between the two instruments Arbitrary User Waveforms The arbitrary waveform memory is capable of storing one or more user defined waveforms As was dis...

Страница 27: ... 3 respectively The sequence generator takes these three waveforms links and loops them in a predefined order to generate the waveform shown in Figure 1 5d The sequence circuit is useful for generating long waveforms with repeated sections The repeated waveform has to be programmed once and the repeater loops on this segment as many times as selected When in sequenced mode there is no loss of time...

Страница 28: ...t connector by a mechanical switch relay This feature is useful for connecting the main outputs to an analog bus For safety reasons when power is first applied to the chassis the main output is always off Filters Two filters are built into the PXA125 These filters are available for use in various applications such as the creation of high frequency sine waves and removing the staircase effect from ...

Страница 29: ...re driver be installed in the host computer The rest is a matter of practice and knowledge of the language in use These topics are discussed in later chapters Low level programming of the PXA125 is accomplished using SCPI Standard Commands for Programmable Instruments language Programming aspects are covered in Chapter 4 Supplied with the PXA125 is a PC software package called ArbConnection This s...

Страница 30: ...ssociated computer Although some instruments and accessories would normally be used with non hazardous voltages there are situations where hazardous conditions may be present This product is intended for use by qualified persons who recognize shock hazards and are familiar with the safety precautions required to avoid possible injury The following sections contain information and cautions that mus...

Страница 31: ...l level which is applicable for equipment measuring terminals that are connected to source circuits in which measures are taken to limit transient voltages to an appropriately low level Pollution Degree 2 refers to an operating environment where normally only dry non conductive pollution occurs Occasionally a temporary conductivity caused by condensation must be expected The PXA125 operates from w...

Страница 32: ...age Abnormal Conditions WARNING Any use of the PXA125 in a manner not specified by the manufacturer may impair the protection provided by the instrument Long Term Storage or Repackaging For Shipment If the instrument is to be stored for a long period of time or shipped immediately proceed as directed below If you have any questions contact your local LeCroy representative or the LeCroy Customer Se...

Страница 33: ...ing the PXA125 An attempt to insert or remove the instrument while the power is connected to the chassis will result in severe damage to the instrument and will automatically revoke your warranty CAUTION Once the PXA125 is installed in the chassis cover all remaining open slots to ensure proper airflow Using the PXA125 without proper airflow will result in damage to the instrument Installing Instr...

Страница 34: ...igure 2 8 and remove the Arbitrary Waveform Generator Model PXA125 under the LeCroy heading In general installation is very similar for different Windows variants however you should follow the exact procedure as applicable for you re your computer The following paragraphs will guide you through device driver installation for Windows 95 98 ME Windows 2000 XP and Windows NT Windows 95 98 ME Device D...

Страница 35: ...ge box 5 Windows displays the Add New Hardware Wizard as shown in Figure 2 1 which will search for new drivers 6 Follow the procedure as shown below 7 After installing the PXI PXA125 successfully see the previous section you ll be prompted to reboot your computer Figure 2 1 Add New Hardware Wizard Press Next and select one of the options in the dialog box below We recommend that you check the Sear...

Страница 36: ...r as shown in Figure 2 3 The PXA125 is supplied with installation CD Insert this CD into your CD ROM drive and check the Specify a location option as shown below If you already have the INF installed somewhere on your computer you can specify your custom location Either type in the complete path or click on the Browse button to find the path to your previous driver location ...

Страница 37: ...llation 2 23 Figure 2 3 Specify PXA125 Driver Location Assuming that this is your first time installation press Browse find the Win9xdrv subfolder that is located in the Drivers folder on the supplied CD as shown in Figure 2 4 ...

Страница 38: ... for Your instrument Press OK then next Windows will automatically detect the device driver and will show the next dialog box as shown in Figure 2 5 Check the device description to make sure it agrees with your instrument description Figure 2 5 Device Driver Detected ...

Страница 39: ...ies the files from the CD ROM drive to your hard drive as shown in Figure 2 6 Figure 2 6 Copying Device Driver After Windows has completed copying the device drivers you can click on the Finish button to complete the installation process Figure 2 7 Finish Copying Device Driver ...

Страница 40: ...and then Control Panel 2 In the Control Panel dialog box find the icon labeled System 3 Double click on the System icon and then on the Device Manager tab 4 Click on LeCroy If you installed the driver properly your device manager should show the Arbitrary Waveform Generator Model PXA125 as shown in the figure 2 8 below Figure 2 8 Checking Driver Installation Click on Cancel to remove the System Pr...

Страница 41: ...indows refers to an INF file The INF file provides instructions for Windows as to which driver files to install and which registry entries to insert To install a driver for your PXA125 complete the following steps 1 Power down your computer and PXI chassis 2 Insert the PXI PXA125 board into a free PXI slot 3 Power on your PXI chassis 4 Power on the computer Windows should first detect the new hard...

Страница 42: ...Figure 2 10 Install Hardware Device Drivers Press Next and you ll now be prompted to select the location of your driver files on your computer as shown in Figure 2 11 Check the Specify a Location option only Figure 2 11 Locate Driver Files ...

Страница 43: ...l automatically load the autorun program and the CD interface will show on your monitor similar to what you see in Figure 2 16 The CD menu is not required for the driver installation so you can either leave the menu on screen and ignore it for now or click on Exit to remove the application from your desktop The installation CD must be left in the CD Rom drive for the continuation of the installati...

Страница 44: ...tion Windows displays the Driver Files Search Results as shown in Figure 2 13 Click Next and then Finish to complete the installation process Figure 2 13 Driver Files Search Results Figure 2 14 Completing the Found New Hardware Wizard ...

Страница 45: ...ontrol Panel 2 In the Control Panel dialog box find the icon labeled System 3 Double click on the System icon and then on the Hardware 4 On the Hardware tab click on the Device Manager button 5 Click on LeCroy If you installed the driver properly your device manager should show the Arbitrary Waveform Generator Model PXA125 as shown in figure 2 15 Figure 2 15 Device Manager Click on X to remove the...

Страница 46: ...uter 5 Insert the CD into your CD ROM drive 6 Start installing the software using the procedure for Installing ArbConnection and ArbDetector utilities as described below Installing ArbConnection and ArbDetector ArbConnection and ArbDetector are two software utilities that must be installed on your computer for you to be able to operate and control the PXA125 ArbConnection has three basic function ...

Страница 47: ... the supplied CD into your CD ROM drive and wait for a GUI Graphical User Interface as shown in Figure 2 16 to pop up on your screen If you wait for a long time and the GUI fails to load it is possible that your computer is not set up to load CD programs automatically In this case Invoke Run and type N Autorun exe where N is your CD drive letter Figure 2 16 CD s GUI To install the software click o...

Страница 48: ...e select the Copy Developer Libraries option and specify the folder location for your application The function of the libraries and other programming aspects are cover in the programming section of this manual Figure 2 17 Install preparation After finishing the Preparing to Install phase the install wizard shown in Figure 2 18 will take you to the first installation step assuming that no problems ...

Страница 49: ... Manual PXA125 Installation 2 35 Figure 2 18 First Installation Step Press Next and type the customer details at the Customer Information Window as shown in Figure 2 19 Figure 2 19 Customer Information Step ...

Страница 50: ...using options 1 or 2 above and complete the installation process by clicking on the Next button and then Finish If you select the Custom option then you ll have to type in some other parameters such as new path for your destination folder and choosing which feature to install as shown in Figures 2 21 and 2 22 Figure 2 20 Selecting Setup Type If you select the Custom option proceed to change your D...

Страница 51: ...ser Manual PXA125 Installation 2 37 Figure 2 21 Selecting Destination To select the Installed Features as shown in Figure 2 22 select the appropriate feature by clicking on Figure 2 22 Selecting Features ...

Страница 52: ...Connection will still launch at startup but the icon will not show and then to access ArbDetector you ll have to invoke it from the Start Programs StartUp Menu The ArbDetector icon selection dialog box is shown in Figure 2 23 Figure 2 23 Selecting ArbDetector Icon options The final step to complete the installation process you ll be prompted to restart your computer You can select to either restar...

Страница 53: ...he PXA125 you must make sure that the ArbDetector has been invoked Look at your right lower end of your screen and identify the Startup bar The ArbDetector icon looks as shown in Figure 2 25 The ArbDetector is automatically invoked from the startup menu after you power on your computer If for any reason you cannot find the ArbDetector icon you ll have to invoke it manually From the Start button se...

Страница 54: ...ou want to Exit the program The ArbDetector icon options is shown in Figure 2 26 Figure 2 26 ArbDetector Icon Options Using the ArbDetector To invoke the ArbDetector program either double click on the icon or open the options window as shown in Figure 2 26 and click on the Open ArbDetector command Doing so the dialog box as shown in Figure 2 27 will open If you cannot see the icon in your system t...

Страница 55: ...mber It also will show the firmware version and its release date Notice the Actual Location fields There are two parameters there that are user controllable These are the chassis number and actual slot location These parameters can be programmed in the Setting tab If you have only one instrument in your system and do not care about its actual and physical location in the system then you do not hav...

Страница 56: ...sign the Chassis number and Slot parameters To add or edit these parameters click on the Edit button The Edit dialog box will display as shown in Figure 2 29 Figure 2 29 Editing Chassis Number and Slot location In the Slot Number field select your actual location of your instrument and in the Chassis Number select the actual chassis where your ...

Страница 57: ... SCPI programming is covered in Chapter 4 of this manual Connect your instrument to an oscilloscope and try these simple commands just to see you re your instrument responds correctly output on will turn on your output and sinewave will be frequency 2e6 will change output frequency to 2 MHz volt 5 will change output amplitude to 5 Vp p If you are not sure about the commands and want the Command Ed...

Страница 58: ...User Manual PXA125 2 44 Installation Figure 2 30 Communicating with your Instrument ...

Страница 59: ... and installed PXA125 6 Last but not least some basic knowledge on how to operate computers and Windows based programs ArbConnection operation is divided into three main functions 1 Front panel control 2 Waveform generation and editing and 3 FM waveform generation and editing These operating options are described in this chapter But you must install ArbConnection before you can use it so the next ...

Страница 60: ...ou can t find the answer to a question in this guide call your distributor or the LeCroy customer support service near you and we ll gladly assist you with your problems For the Advanced User If you are already familiar with computer conventions and have basic knowledge of Windows programming you may want to skip some of the following paragraphs Conventions Used in This Manual This manual uses cer...

Страница 61: ...gure 3 1 Figure 3 31 The opening Screen The Startup Communication Options dialog box is displayed at the top You can check the Store and don t show so next time you invoke ArbConnection this dialog box will not be displayed The purpose of this dialog box is to update the program in the way you intend to use it Since ArbConnection is used for other platforms it is extremely important to make sure t...

Страница 62: ... the next time you invoke the program the control panels are updated from this image When you use the Update Instrument option the instrument will update its operational settings and parameter values only but will not download waveforms Refresh Communications will activate the Autodetect engine and will attempt to reconnect all devices that respond to ArbConnection calls The use of this option is ...

Страница 63: ...tandard Windows Menu Bar is the top bar It provides access to main system controls like saving files and viewing or removal of screen images Some of the File commands such as New Open Save and Save As are also available as icons The second bar is called Active Instrument bar It provides direct access to different instruments that are plugged into the PXI chassis ArbConnection can operate many PXA1...

Страница 64: ...poser and 3 FM waveform composer The various screens along with instructions how to access and use them are described below in detail The Control Panels The control panels look and feel just as if you would operate an instrument from its front panel They even look like a front panel of an instrument so operating function and changing parameters are very intuitive Lets look at the first panel that ...

Страница 65: ...e next to this LED is selected Only one LED can be ON at a time HINT LED s may be turned on by pressing the button below You can also select an LED by clicking on the LED itself Dial Use the dial to modify displayed reading To use the dial press and hold the mouse cursor on the dial and move the mouse in a clockwise circle to increase the number or counterclockwise circle to decrease the displayed...

Страница 66: ... backplane trigger line outputs and turning ON or OFF the main output Figure 3 33 The Main Panel If you are connected properly to the PCI bus and ArbConnection has detected this link and placed the address in its Link field then every time you press a button you are getting an immediate action on the PXA125 It is different if you are changing parameters on the display Doing this you ll have to pre...

Страница 67: ...he new trigger option and the Trigger Panel will pop up allowing adjustments of trigger parameters SYNC Output The SYNC Output group controls SYNC parameters and enables or disables the SYNC output The SYNC output is enabled when the State button is ON The SYNC Width and Position parameters will affect the PXA125 when the BIT validator is selected In LCOM mode the width and the position will have ...

Страница 68: ...lay You can use the dial keyboard or the keys to adjust the readout to the required setting After you modify the reading press Execute to update the PXA125 with the new reading Note Normal color of the digital reading is dark blue If you modify the reading the color changes to a lighter shade of blue indicating that the PXA125 has not been updated yet with the new parameter Pressing Execute will u...

Страница 69: ...and will also allow removal of the Waveforms Panel from the screen 10 MHz Ref The 10 MHz Ref group provides selection between internal or external references The PXA125 has three reference options Internal connects the CLK10 reference from P2 to the sample clock generator The accuracy and stability of the CLK10 is around 100ppm Note Compact PCI chassis do not have P2 connectors on their backplanes...

Страница 70: ...election you ll be granted access to parameters that are unique for this function For example if you click on the Square button the Duty Cycle parameter will be available for modification Likewise if you select the pulse shape the fall high rise and delay parameters will be available for modification Note that by clicking a button in this group you are immediately updating the PXA125 output with t...

Страница 71: ...eter turns on The value that is associated with the lit LED is displayed on the digital display You can use the dial keyboard or the keys to adjust the readout to the required setting After you modify the reading press Execute to update the PXA125 with the new reading Note Normal color of the digital reading is dark blue If you modify the reading the color changes to a lighter shade of blue indica...

Страница 72: ...play You can use the dial keyboard or the keys to adjust the readout to the required setting After you modify the reading press Execute to update the PXA125 with the new reading 10 MHz Ref The 10 MHz Ref group is a duplicate of the same group in the Main Panel The 10 MHz Ref group provides selection between internal CLK10 external or TCXO references Click on the Internal button to select the Inter...

Страница 73: ...ects the trigger source to one of eight backplane trigger lines Besides the grouped controls there are five other buttons available on the Arbitrary Sequence Panel These buttons provide access to from top to bottom Wave Composer Sequence Table Segment Table Main Panel The last button removes the Arbitrary Sequence Panel from the screen The Wave Composer will be discussed separately in this chapter...

Страница 74: ...se on the To Segment Table button A dialog box as shown in Figure 3 6 will pop up Figure 3 36 The Segment Table The Channel field lets you select the active channel If 1 is displayed then the table you ll be constructing will affect channel 1 Likewise select 2 if you want to program the table for channel 2 The two main fields in the segment table are Seg and Length The Seg segment is an index fiel...

Страница 75: ... be loaded to the instrument from a computer before it can generate sequences The waveforms are downloaded as coordinates and are stored in the PXA125 is a place designated as waveform memory The waveform memory has a finite size of 2Meg As was explained in Using the Segment Table above the waveform memory can be divided into smaller segments and up to 4096 segments can be defined and used as indi...

Страница 76: ...m 2 the waveform will cycle twice through the same segment before transitioning to the next link Segment associates waveform segments with links You can use different segments for different links or you can use the same segment for a number of links There are no limitations how you associate links to segments except you cannot program in the sequence table segments that were not defined earlier Ad...

Страница 77: ...this table it will have the same contents as you saved in your previous session The Trigger Panel The Trigger panel as shown in Figure 3 8 is invoked either by pressing the TRIG button on the Panels bar or clicking on one of the Triggered Gated or Burst buttons on the Main Panel Note that if you invoke the Trigger Panel from the Panels menu the PXA125 will not change its operating mode On the othe...

Страница 78: ...rigger Panel Slope The Slope group lets you select edge sensitivity for the trigger input of the PXA125 If you click on Positive the instrument will trigger on the rising edge of the trigger signal Likewise if you click on Negative the instrument will trigger on the falling edge of the trigger signal Source The Source group provides access to trigger source parameters Click on External to enable t...

Страница 79: ...Main Panel The modulation panel provides access and control for a number of functions FM frequency modulation FSK frequency shift keying and Sweep The PXA125 can perform only one of these functions at a time and ArbConnection will generate an error if you try to change the state to on for more than one modulation option The functional groups in the Modulation Panel are divided to three parts Frequ...

Страница 80: ...sm for the high and low limits You cannot exceed the limits if you are using the dial but only if you use the keypad In case you do the program will not let you download an illegal parameter and you ll be requested to correct your setting Mode The Mode sub group let you select one of the FM operating modes You have a choice of continuous triggered and gated FM Unlike the main trigger function the ...

Страница 81: ...ters Allow adjustment of Ramp Time and Shifted Sample Clock frequency parameters To access the required parameter click on the button below parameters sub group until the LED next to the required parameter turns on The value that is associated with the lit LED is displayed on the digital display You can use the dial keyboard or the keys to adjust the readout to the required setting After you modif...

Страница 82: ...o the program will not let you download an illegal parameter and you ll be requested to correct your setting Direction Use the keys in this sub group to program sweep direction Up select sweep from start to stop sample clock setting and Down selects sweep from the stop to start sample clock setting Refer to Chapter 3 of this manual to learn more about sweep operation Type Use these keys to select ...

Страница 83: ...ple instruments and program phase offsets between instruments Phase offset is applied between the leading edges of the two instruments and is given in units of waveform points To adjust the Ph Offset parameter click on the button below parameter The LED next to the Ph Offset turns on The offset value is displayed on the digital display You can use the dial keyboard or the keys to adjust the readou...

Страница 84: ...ronized instruments Instruments plugged to the left of the master will automatically be excluded from synchronization and their Couple State set to OFF 4 One more or all instruments to the right of the master unit can be slaved If you do not want to slave an instrument you must configure its Couple State to OFF 5 Master and Slave units must be adjacent If you set the Couple State for one of the in...

Страница 85: ...onfigured in the Multi Instrument Synchronization Panel If you pressed this button without first configuring master and slave units the error message as shown in Figure 3 12 will be shown The Activate button must be pressed after you change waveforms phase offset operation modes etc You do not need to press this button if you change sample clock amplitude and offset or other parameters that do not...

Страница 86: ...cation link such as MXI3 Not only that the instrument must be connected but also software and registers must be set properly for the generator to function properly It is also possible that your computer is running smoothly but the PXA125 has problems communicating with your computer The System and Command Editor dialog box has all the tools needed to make sure that the PXA125 is connected properly...

Страница 87: ... resetting the instrument to factory defaults The TST Invokes selftest routines It is not relevant for the PXA125 and therefore blanked out in this dialog box You should use this test when you suspect that something is wrong with your instrument The PXA125 executes this test and generates a response that is placed in the field below the TST button The response to the selftest command is numeral An...

Страница 88: ...s so use the following paragraphs to learn how to create edit and download waveforms to the PXA125 using the Waveform Composer You can invoke the Waveform Composer program from two places On the Panels bar click on WAVE or from the Arbitrary Sequence Panel click on To Wave Composer Figure 3 14 shows the waveform composer immediately after you first invoke this utility The Wave Composer has three s...

Страница 89: ...e composer program Description of the various commands under File is given below New Waveform The New Waveform command clears current waveform from the screen If you made changes to the waveform area and use the New Waveform command you should save your work before clearing the screen The New Waveform command is destructive to the displayed waveform Open Waveform The Open Waveform command will let...

Страница 90: ... will store your active waveform in your PXA125 directory as a binary file with an wav extension If this is the first time you save your waveform the Save Waveform As command will be invoked automatically letting you select name location and format for your waveform file Save Waveform As Use the Save Waveform As command the first time you save your waveform It will let you select name location and...

Страница 91: ... of a parabolic curve Note that small segments with fast transitions when combined with parabolic expressions have tendencies to generate even larger transitions Therefore make sure you omit such sections of the waveform when you use this operation Filter The Filter used with this command is moving average This is done by recalculating each point as an average of symmetrical number of adjacent poi...

Страница 92: ...Hide Show Toolbar Description of the view commands is given in the following Zoom In You may zoom in on portions of the waveform by dragging the left and right anchors to the area you want to zoom then use the Zoom In command The example in Figure 3 16 shows a magnified portion of the waveform while the smaller window shows the complete waveform map and the portion you magnified You can click and ...

Страница 93: ...create waveforms using the Equation Editor Information how to create waveforms using the Wave commands is given below Creating Waveforms From the Built in Library You can create any waveform from the built in library using the Wave command Clicking on one of the Wave options will open a dialog box An example of the Sine waveform dialog box is shown in Figure 3 17 This dialog box is representative ...

Страница 94: ...an now start programming parameters that are available in this box Start Point Defines the first point where the created wave will start Note that if you change the start point the left anchor will automatically adjust itself to the selected start point The example shows start point set at point 0 End Point Defines where the created waveform will end Note that as you change the end point the right...

Страница 95: ...the power of 1 will generate a perfect sine Power range is from 1 through 9 System Commands The System commands let you do two actions Delete all segments and download the active waveform to the selected channel Both of these commands are also available as icons on the toolbar The Toolbars The toolbar contains icons for editing the waveform screen icons for saving and loading waveforms fields for ...

Страница 96: ...this icon Click on this icon again or click your right mouse button to terminate the sketch mode The Sketch command lets you draw free hand segments To draw a line using this command click and hold the left mouse button at the start point Release the mouse button when you want to stop and then click on the right mouse button to terminate this operation Clicking on this icon will invoke the smooth ...

Страница 97: ...rea enclosed between one or two anchors To move the anchors click and hold on the triangle on top of the waveform screen than drag the anchor to the desired location If you want to specify anchor location place your mouse on the triangle and click the right button on your mouse type in the anchor location and press Enter Use this icon after you have zoomed in to view the entire waveform area When ...

Страница 98: ...nique waveform length To select a new active segment click on the edit field use your backspace or delete keys to clear the field and type in the new number To complete the selection click on the Active Segment button The Waveform Screen Waveforms are created and edited on the waveform screen Figure 3 19 shows an example of a waveform created using the equation editor and the anchors to limit gene...

Страница 99: ...he right at point 500 and then generate the sine from the built in library There are two ways to control anchor placements 1 Click and hold your mouse cursor on the left anchor triangle and then drag the curtain to the left position Do the same for the right anchor Notice the X and Y coordinates at the top of the waveform screen and how they change to correspond to your anchor placement 2 You can ...

Страница 100: ...unsurpassed and can only be duplicated by mathematical simulation The FM composer is loaded with many features and options so use the following paragraphs to learn how to create and download modulating waveforms to the PXA125 using the FM Composer You can invoke the FM Composer from two places On the Panels bar click on FM or from the Modulation Panel click on To FM Composer Figure 3 20 shows the ...

Страница 101: ...the waveform from the screen If you made changes to the waveform area and use this command you should save your work before clearing the screen The New Waveform command is destructive to the displayed waveform Open Waveform The Open Waveform command will let you brows your disk for previously saved waveform files and load these waveforms to the waveform area This command is also very useful for co...

Страница 102: ... file Save Waveform As Use the Save Waveform As command the first time you save your waveform It will let you select name location and format for your waveform file The Save As dialog box is shown in Figure 3 21 Figure 3 51 The FM Composer Save AS Dialog Box Exit The Exit command ends the current FM Composer session and takes you back to the Panels screen If you made changes to your waveform since...

Страница 103: ...ately to follow the mathematical pattern of a parabolic curve Note that small segments with fast transitions when combined with parabolic expressions have tendencies to generate even larger transitions Therefore make sure you omit such sections of the waveform when you use this operation Filter The Filter used with this command is moving average This is done by recalculating each point as an avera...

Страница 104: ...nes where the created waveform will end Note that as you change the end point the right anchor will automatically adjust itself to the selected end point The example shows end point set at point 499 Max Peak Deviation This parameter defines the forward peak deviation Note that the forward peak deviation cannot exceed the pre defined Deviation parameter as shown on the Toolbar In case you need to e...

Страница 105: ... write equations the same way as you would do on a blank piece of paper The equations are then translated to sequential points that form waveforms and are displayed on the waveform screen The Equation Editor will detect and inform you on syntax errors and with its self adjusting feature will automatically adjust your parameters so that none of the points on your waveform will exceed the maximum sc...

Страница 106: ...ifying your equation The Level Adjuster mode does not interfere with your calculations and displays the waveform as computed from your equation The only difference is that your final calculations are stretched or shrunk or offset on the vertical scale to fit the new amplitude and offset boundaries For example look at the equation that is shown in Figure 3 23 This equation will generate a waveform ...

Страница 107: ...oints as a function of the vertical scale Each vertical sample is computed separately and placed along the horizontal axis The points are graphically connected to form a continuous waveform However if you zoom in on a waveform line you ll see that the points are connected like a staircase In reality the PXA125 generates its waveforms exactly as shown on the screen however if the waveform has many ...

Страница 108: ... power Multiply Divide Add Subtract Parentheses e Base of natural Logarithm pi π Circumference of unit diameter circle per Horizontal wavelength in points f I per omg Ω 2 π per amp Amplitude in units of points or seconds sin x The sine of x cos x The cosine of x tan x The tangent of x ctn x The cotangent of x log x The base IO logarithm of x In x The natural base e logarithm of x abs x The absolut...

Страница 109: ... the screen The Wave Composer did not make a mistake The sine of 10 in radians is exactly what it shows You are unable to see the result because the line on your screen running across the 0 vertical point REMEMBER The equation must be a function of a single variable and that variable must be directly related to the Horizontal axis Scale setting Now try this Ampl p sin omg p Still no good but now p...

Страница 110: ...interesting Take the straight line equation and add it to the sinewave equation Ampl p 6000 sin omg p l0 2 p 2000 Press Preview Your screen should look like Figure 3 24 Figure 3 54 Using the Equation Sample to Combine Two Waveforms Now lets try to modulate two sinewaves with different periods and different start phase Type this Ampl p 8000 sin omg p cos omg p 30 Press Preview Your screen should lo...

Страница 111: ... standard sinewave The original waveform had a peak to peak value of 5000 points so 20 second harmonic is equivalent to 1000 points The frequency of the second harmonic is obviously double that of the fundamental so term 1000 sin 2 omg t is added to the original sine wave equation Use the following equation Ampl p 5000 sin omg t 1000 sine 2 omg t Press Preview Your screen should look like Figure 3...

Страница 112: ...ed 10 cycles of sinewave made to decay exponentially The original expression for a standard sinewave is multiplied by the term e t 250 Increasing the value of the divisor 200 in this case will slow down the rate of decay Use the following equation Ampl p 8000 sin omg t 10 e t 250 Press Preview Your screen should look like Figure 3 27 ...

Страница 113: ...de modulated with 10 cycles of sine wave with a modulation depth of 20 To achieve this the upper and lower sidebands are defined separately and added to the fundamental or carrier The upper sideband is produced by the expression 100 cos 110 omg t and the lower sideband by the term 100 cos 90 omg t Use the following equation Ampl p 5000 sin 100 omg t 1000 cos 110 omg t 1000 cos 90 omg t Press Previ...

Страница 114: ...our equations you must first generate these waves and store them on your hard disk You identify waveforms by adding the wav extension as shown in the example below Ampl p Sine wav sin omg p 10 Noise wav 1000 The above equation will generate amplitude modulated waveform with added noise The following steps demonstrate how to create store and combine waveforms using this equation Step 1 Create and s...

Страница 115: ...m the File menu select Save Waveform As and save this waveform using the name Noise wav Step 3 Write and compute the original equation Ampl p Sine wav sin omg p 10 Noise wav 1000 If you did not make any mistakes your waveform screen should look as shown in Figure 3 29 Figure 3 59 Combining Waveforms Into Equations ...

Страница 116: ...ld convert the units using the following equation Frequency Sample clock frequency n where n number of points of the modulating curve For example if you look at Figure 3 30 the first marker position is 7 2006 MSa s and the number of point on the horizontal axis is 1000 points 0 to 999 1000 The actual marker frequency is 7 2006 MSa s 1000 7 2006 KHz After you complete writing maker positions and if...

Страница 117: ...lating waveform with the marker positions that you assigned in the table If you press Close without first Store Update you ll lose data entry You can also use this button in case you want to discard of faulty data entries Figure 3 60 Generating FM markers ...

Страница 118: ...User Manual PXA125 3 104 ArbConnection This page intentionally left blank ...

Страница 119: ... in various folders of your computer Check that you have all of these files before you start with your own application When you run the install program from the supplied CD the installation program will automatically generate a folder with the name PXA125 In this folder you ll have three other sub folders Bin Include and Lib MSC Check in the Bin sub folder that you have TEComm dll and te5200drv dl...

Страница 120: ...User Manual PXA125 Programming Reference 4 2 ...

Страница 121: ...ns the number of instruments that it found C Syntax INSTRUMENTSTATE FindInstrument PDWORD pItems Resource Classes PXI PCI Parameters Name Description pItems Returns the number of PXA125 s in the system Return Values Completion Codes Description PCI_SUCCESS Function executed without errors Error Codes Description ...

Страница 122: ... Therefore you must use this function in your program before you use any other functions The information that this function provides is handy for the OpenInstrument function because it tells you how many instruments established valid communication link Once you have this piece of information you can decide which one to open and use in your application The FindInstrument function returns an integer...

Страница 123: ...Name Description hInstr Instrument handle number Must be out of a range of instruments that were found in the PXI baskets The numbers start at 0 for first device to n 1 This value is extracted using the TEComm dll function FindInstrument Return Values Completion Codes Description PCI_SUCCESS Function executed without errors PCI_INS_ALREADY_OPEN Trying to establish new communication link while inst...

Страница 124: ...ription The OpenInstrument function can be used only after you initiate communication with your instruments using the function FindInstrument This function enables communication and assigns a handle to specific device number For example if you want to use device number 2 set the value of hInstr to 1 Likewise if you want to use device number 8 set the value of hInstr to 7 ...

Страница 125: ...Instrument void Resource Classes PXI PCI Parameters None Return Values Completion Codes Description PCI_SUCCESS Function executed without errors PCI_INS_ALREADY_OPEN Trying to establish new communication link while instrument has already been connected Error Codes Description PCI_ERR_OPEN_INS_FAILED Could not succeed to initiate communications with the selected instrument ...

Страница 126: ...Instrument function can be used only after you initiate communication with your instruments using the function FindInstrument This function enables communication and assigns handles to all of the instruments at once In this case you do not have to specify device numbers ...

Страница 127: ...Instr Instrument handle number Must be out of a range of instruments that were found in the PXI baskets The numbers start at 0 for first device to n 1 This value is extracted using the TEComm dll function FindInstrument Return Values Completion Codes Description PCI_SUCCESS Function executed without errors PCI_INS_ALREADY_OPEN Trying to establish new communication link while instrument has already...

Страница 128: ...X_OF_INS_NOT_EXIST Illegal index number used to identify an instrument Description Use this function if you want to remove the handle from one or more instruments After you free the handle you will not be able to access the instrument before you use the Openinstrument function again ...

Страница 129: ...ce Classes PXI PCI Parameters Name Description hInstr Instrument handle number Must be out of a range of instruments that were found in the PXI baskets The numbers start at 0 for first device to n 1 This value is extracted using the TEComm dll function FindInstrument pInstrAttr Attributes structure The structure is available in TEComm h INSTRATTR Return Values Completion Codes Description PCI_SUCC...

Страница 130: ...STRATTR m_Type Describes the model number For example PXA125 m_Description Provides description of the instrument Arbitrary Waveform Generator m_BasicModel Provides in formation on maximum sample clock frequency 125 MS s for the PXA125 m_MemSize Provides information on the installed memory There are 2 Megs avail able m_ClockOption Provides information on TCXO The return will be TCXO m_Customer Pro...

Страница 131: ...assis number and the slot location must be defined by the user using the Arb Detector from the Startup menu Instrument Attributes Structure INSTRPHISICALLOCATION m_Bus Provides information on the bus number the instrument was found on m_Slot Provides information on the slot location that was assigned by the com puter Note that physical location and logical location are not the same You can program...

Страница 132: ...able in TEComm h pMsg Returns a string identifying the error Size Assigned buffer size for the returned string Return Values None Description Use this function to detect errors while sending commands to the instrument Errors could generate from not being able to communicate with the devices or from sending illegal SCPI syntax Setting conflicts are also common source for errors The GetStateMessage ...

Страница 133: ...g SendCommand Purpose Use this function to send SCPI commands to the instrument C Syntax INSTRUMENTSTATE SendCommand int hInstr char inbuf Resource Classes PXI PCI Parameters Name Description hInstr Instrument handle number Must be out of a range of instruments that were found in the PXI baskets The numbers start at 0 for first device to n 1 This value is extracted using the TEComm dll function Fi...

Страница 134: ...000000 look for problems in the communication with the PXA125 Most probable cause for such errors is not invoking the Arb Detector program after you power up your computer Description The SendCommand function is the main function you ll use for controlling instrument functions and parameters The PXA125 is using Standard Commands for Programmable Instruments SCPI The following paragraphs describe S...

Страница 135: ...hout the hassle of learning the syntax you d better start with series of commands and later as you get familiar with the programming aspects you can start using shorted command lines 2 Later in this chapter you ll find all of the commands that are used for programming the instrument This reference is the complete and only source you ll need for your application However if you want to save some tim...

Страница 136: ...ment pFileName Use this parameter to define if the waveform coordinates are located in an external file or reside inside the program NULL define resident coordinates file_name define name and path of external file You can use complete path if file location is outside the working folder pWave Pointer for memory space where the coordinates of the arbitrary waveform can be found If you are using exte...

Страница 137: ...g to instrument setability SCPI error list is given in the SCPI Commands reference If value is larger than 0x8000000 look for problems in the communication with the PXA125 Most probable cause for such errors is not invoking the Arb Detector program after you power up your computer Description The PXA125 is a waveform generator There are three types of waveforms that the instrument can generate 1 S...

Страница 138: ...your application Two examples are given Using the SendBlock function with resident data array and using SendCommand with an exter nal data file Example 1 1 Use SendCommand to program Trac sel 1 2 Use SendCommand to program Trac def 1 1000 3 Prepare your waveform data 4 Call SendBlock hInstr 1 void wav 1000 2 Note that each data point requires 2 bytes Example 2 1 Use SendCommand to program Trac sel...

Страница 139: ...int 0x01 for marker position 0x00 for all other points 4 Convert pt component of array to long format Intel binary representation if neces sary 5 Call DLL function SendBlock hInstr 2 void fmWav wavelength 5 Note that the arbitrary FM waveform data array is comprised of 5 bytes The most significant 4 bytes contain waveform data The lease significant byte last flags marker position and end of data f...

Страница 140: ... values returned by the instrument SCPI is an ASCII based instrument command language designed for test and measurement instruments SCPI commands are based on a hierarchical structure known as a tree system In this system associated commands are grouped together under a common node or root thus forming subsystems Part of the OUTPut subsystem is shown below to illustrate the tree system OUTPut FILT...

Страница 141: ...nclosed in triangular brackets The brackets are not sent with the command string A value for the frequency parameter such as FREQ 50e 6 must be specified Some parameters are enclosed in square brackets The brackets indicate that the parameter is optional and can be omitted The brackets are not sent with the command string Command Separator A colon is used to separate a command keyword from a lower...

Страница 142: ...values or settings of the generator Commands that set values can be queried for their current value Commands that set modes of operation can be queried for their current mode IEEE STD 488 2 common queries generate responses which are common to all IEEE STD 488 2 compatible instruments SCPI Command Terminator A command string sent to the function generator must terminate with a new line character T...

Страница 143: ...ER and SEQuence They have short and long form command keywords Upper and lowercase letters can be mixed Query responses always return the short form in all uppercase letters The following command uses discrete parameters SOUR FUNC MODE FIXed USER SEQuence Boolean Parameters Boolean parameters represent a single binary condition that is either true or false The generator accepts OFF or 0 for a fals...

Страница 144: ...pper case and the long form upper and lower case The PARAMETER FORM column indicates the number and order of parameter in a command and their legal value Parameter types are distinguished by enclosing the type in angle brackets If parameter form is enclosed by square brackets these are then optional care must be taken to ensure that optional parameters are consistent with the intention of the asso...

Страница 145: ... STAR STATe OFF ON SYNC STATe OFF ON SOURce BIT LCOMplete POSition POINt 0 0 n where n is the size of the active segment 4 point increments WIDTh 4 4 100000 4 point increments SOURce APPLy SINusoid FREQ AMPL OFFS PHAS TRIangle FREQ AMPL OFFS PHAS SQUare FREQ AMPL OFFS DCYC PULSe FREQ AMPL OFFS DEL WIDT LEAD TRA RAMP FREQ AMPL OFFS DEL LEAD TRA SINC FREQ AMPL OFFS NCYC GAUSsian FREQ AMPL OFFS EXP E...

Страница 146: ...Set 0 3 6 3 6 FUNCtion MODE FIXed USER SEQuence SHAPe SINusoid TRIangle SQUare PULSe RAMP SINC GAUSsian EXPonential NOISe DC SINusoid PHASe 0 0 360 TRIangle PHASe 0 0 360 SQUare DCYCle 50 1 99 PULSe DELay 10 0 99 9 WIDth 10 0 99 9 TRANsition LEADing 10 0 99 9 TRAiling 10 0 99 9 RAMP DELay 0 0 99 9 TRANsition LEADing 60 0 99 9 TRAiling 30 0 99 9 GAUSsian EXPonent 20 10 200 SINC NCYCle 10 4 100 EXPo...

Страница 147: ...OFF ON TRIGger MODE CONTinuous TRIGgered GATed SLOPe POSitive NEGative FSK FREQuency RASTer 80e6 100e 3 100e6 STATe OFF ON MODE HOP RAMP RAMP TIME 1e 3 10e 6 1 SWEep FREQuency STOP 20e6 100e 3 100e6 STATe OFF ON TIME 1e 3 1e 3 1000 DIRection UP DOWN SPACing LINear LOGarithmic TRIGger CONTinuous TRIGgered GATed MODE CONTinuous TRIGgered GATed SLOPe POSitive NEGative MARKer 20e6 100e 3 100e6 TRACe D...

Страница 148: ...t repeat advance mode DELete ALL INITiate IMMediately CONTinuous ON OFF TRIGger BURSt STATe OFF ON COUNt 1 1 1E6 SOURce ADVance EXTernal INTernal TTLTrig 0 7 STAR GATE STATe OFF ON SLOPe POSitive NEGative TIMer 1e3 100e 3 5e6 In Hz units STAR STATe OFF ON PHASe 0 0 n where n is the size of the active segment 4 points increments ARM STATe OFF ON SLOPe STARt POSitive NEGative BREakpoint POSition 0 0...

Страница 149: ...able 4 1 Model PXA125 SCPI Commands List Summary continued Keyword Parameter Form Default in Bold Notes CLS ESE 0 0 255 OPC RST SRE 0 0 255 TRG ESE Query only ESR Query only IDN Query only OPC Query only OPT Query only SRE Query only STB Query only ...

Страница 150: ...fs FM OFF ON 0 1 OFF DEViation deviation 1e6 100e 3 100e6 FUNCtion MODE FIXed USER FIXed SHAPe SINusoid TRIangle SQUare RAMP SINusoid FREQuency FM_freq 1e3 1e 3 100e3 RASTer FM_sclk 1e6 1e 3 10e6 TRIGger MODE CONTinuous TRIGgered GATed CONTinuous SLOPe POSitive NEGative POSitive FREQuency freq MINimum MAXimum 1e6 100e 6 50e6 RASTer sclk MINimum MAXimum 10e6 100e 3 100e6 SOURce EXTernal INTernal IN...

Страница 151: ... 10 200 EXPonential EXPonent exp 20 100 100 DC _amplitude 100 100 100 APPLy SINusoid freq ampl offs phase Purpose This command is a high level command that programs the PXA125 to output sine waveform along with its associated parameters freq sets the output frequency in units of hertz ampl sets the output amplitude in units of volts offs sets the output offset in units of volts phase sets the outp...

Страница 152: ...re 1e6 5 0 0 APPLy SQUare freq ampl offs duty_cycle Purpose This command is a high level command that programs the PXA125 to output square waveform along with its associated parameters freq sets the output frequency in units of hertz ampl sets the output amplitude in units of volts offs sets the output offset in units of volts duty_cycle sets the squarewave duty cycle in units of Parameter type Nu...

Страница 153: ... 99 9 APPLy PULSe Response The PXA125 will return freq ampl offs delay rise high fall Default values are 1e6 5 0 10 10 10 10 APPLy RAMP freq ampl offs delay rise fall Purpose This command is a high level command that programs the PXA125 to output ramp waveform along with its associated parameters freq sets the output frequency in units of hertz ampl sets the output amplitude in units of volts offs...

Страница 154: ...ic Parameter range freq 10e3 to 50e6 ampl 80e 3 to 80 offs 3 6 to 3 6 N_cycle 4 to 100 APPLy SINC Response The PXA125 will return freq ampl offs N_cycle Default values are 1e6 5 0 10 APPLy EXPonential freq ampl offs exp Purpose This command is a high level command that programs the PXA125 to output exponential waveform along with its associated parameters freq sets the output frequency in units of...

Страница 155: ...rn freq ampl offs exp Default values are 1e6 5 0 20 APPLy DC _ampl Purpose This command is a high level command that programs the PXA125 to output DC level along with its associated parameter _ampl sets the output level as percentage of the amplitude setting Parameter type Numeric Parameter range _ampl 100 to 100 in units of APPLy DC Response to query version The PXA125 will return _ampl Default v...

Страница 156: ...User Manual PXA125 Programming Reference 4 38 offs sets the output offset in units of volts Parameter type Numeric Parameter range seg 1 to 4096 sclk 10e 6 to 100e6 ampl 80e 3 to 80 offs 3 6 to 3 6 ...

Страница 157: ...etween the channels Phase offset is in waveform points Parameter type Numeric Parameter range deviation 1e 3 to 100e6 in units of samples per second FM DEViation Response and default The PXA125 will return the present frequency deviation value The returned value will be in standard scientific format for example 100mHz would be returned as 100E 3 positive numbers are unsigned Default value is 1e3 D...

Страница 158: ... present setting Default is SIN FM FREQuency FM_freq Purpose This command will set the modulating wave frequency This parameter affects the PXA125 when set to op erate in FM FUNC MODE FIX FM_freq will set the frequency of the modulating waveform Parameter type Numeric Parameter range FM_freq 1e 3 to 100e6 in units of hertz FM FREQuency Response and default The PXA125 will return the present modula...

Страница 159: ...lation Parameter type Discrete FM TRIGger MODE Response and default The PXA125 will return CONT TRIG or GATE depending on its present setting Default is CONT FM TRIGger SLOPe POSitive NEGative Purpose This command will select slope sensitivity for the FM trigger input POSitive will select rising edge NEGative will select falling edge Parameter type Discrete FM TRIGger SLOPe Response and default Th...

Страница 160: ...AXimum sets the sample clock frequency to its highest value Parameter type Numeric Parameter range sclk 100e 3 to 100e6 FREQuency RASTer Response and default The PXA125 will return the present sample clock frequency value The returned value will be in standard scientific format for example 100MHz would be returned as 100E6 positive numbers are unsigned Default value is 10e6 FREQuency RASTer SOURce...

Страница 161: ...User Manual PXA125 Programming Reference 4 43 ...

Страница 162: ...le 1KHz would be returned as 1E3 positive numbers are unsigned Default value is 80e3 FSK MODE HOP RAMPed Purpose This command will select one of the FSK modes HOP will select non delayed hops from carrier sclk to shifted sclk RAMPed will select ramped shifts from carrier sclk to shifted sclk Parameter type Discrete FSK MODE Response and default The PXA125 will return HOP or RAMP depending on its p...

Страница 163: ...epending on the present PXA125 setting Default value is FIX FUNCtion SHAPe SINusoid TRIangle SQUare PULSe RAMP SINC EXPonential GAUSsian NOISe DC Purpose This command defines the shape of waveform that will be available at the output connector This command has no affect if present PXA125 setting is USER or SEQ SINusoid selects sine waveform TRIangle selects triangular waveform SQUare selects squar...

Страница 164: ...P stop_sclk Purpose This command will set the stop sample clock frequency When set to operate in sweep mode the PXA125 will sweep from carrier sample clock frequency to sweep stop sample clock frequency stop_sclk will set the sweep stop sample clock frequency for the sweep mode Parameter type Numeric Parameter range stop_sclk 100e 3 to 100e6 in units of samples per second SWEep STOP Response and d...

Страница 165: ...p sclk parameter to start frequency set by the sclk parameter Parameter type Discrete SWEep DIRection Response and default The PXA125 will return UP or DOWN depending on the present PXA125 setting Default value is UP SWEep SPACing LINear LOGarithmic Purpose This command will select the sweep spacing from linear spacing and logarithmic spacing LINear will select linear steps LOGarithmic will select...

Страница 166: ...ark_sclk will set the marker sample clock frequency Parameter type Numeric Parameter range mark_sclk 100e 3 to 100e6 in units of samples per second SWEep MARKer Response and default The PXA125 will return the present sweep sample clock frequency value The returned value will be in standard scientific format for example 1KHz would be returned as 1E3 positive numbers are unsigned Default value is 64...

Страница 167: ...User Manual PXA125 Programming Reference 4 49 MAXimum 10 in units of volts ...

Страница 168: ...nse and default The PXA125 will return the present offset value The returned value will be in standard scientific format for example 100mV would be returned as 100E 3 positive numbers are unsigned Default value is 0 SINusoid PHASe phase Purpose This command programs start phase of the standard sine waveform This command has no affect on arbitrary waveforms phase sets the start phase Parameter type...

Страница 169: ...t SQUare DCYCle Response and default The PXA125 will return the present duty cycle value Default value is 50 PULSe DELay delay Purpose This command programs delay of the standard pulse waveform This command has no affect on arbitrary waveforms delay sets the delay parameter Parameter type Numeric Parameter range delay 0 to 99 9 in units of percent PULSe DELay Response and default The PXA125 will r...

Страница 170: ...nt PULSe TRANsition Response and default The PXA125 will return the present rise time value Default value is 10 PULSe TRANsition TRAiling fall Purpose This command programs pulse transition from high to low of the standard pulse waveform This command has no affect on arbitrary waveforms fall sets the fall time parameter Parameter type Numeric Parameter range fall 0 to 99 9 in units of percent PULS...

Страница 171: ...fault The PXA125 will return the present rise time value Default value is 60 RAMP TRANsition TRAiling fall Purpose This command programs ramp transition from high to low of the standard ramp waveform This command has no affect on arbitrary waveforms fall sets the fall time parameter Parameter type Numeric Parameter range fall 0 to 99 9 in units of percent RAMP TRANsition TRAiling Response and defa...

Страница 172: ...nse and default The PXA125 will return the present exponent value Default value is 20 EXPonential EXPonent exp Purpose This command programs the exponent for the standard exponential waveform This command has no affect on arbitrary waveforms exp sets the exponent parameter Parameter type Numeric Parameter range exp 100 to 100 EXPonential EXPonent Response and default The PXA125 will return the pre...

Страница 173: ... Keyword Parameter Form Default Low Limit High Limit OUTPut OFF ON 0 1 OFF FILTer NONE 25M 50M ALL NONE SYNC OFF ON 0 1 OFF SOURce BIT LCOMplete BIT POSition position 0 0 n WIDTh width 4 4 100000 TTLTrig N 1 2 3 4 5 6 7 STATe OFF ON 0 1 OFF STAR 1 2 3 4 5 6 7 STATe OFF ON 0 1 OFF OUTPut OFF ON 0 1 Purpose This command will turn the PXA125 output on and off ON or 1 will set the output on OFF or 0 w...

Страница 174: ...or use only after you select a different waveform or change the output mode to use 2 Filters are placed before the output amplifier Therefore do not expect the filters to remove in band amplifier harmonics and spurious NONE will disconnect all filters from the output path 25M will connect 25 MHz low pass elliptic filter 50M will connect 50 MHz low pass elliptic filter ALL will connect both the 25 ...

Страница 175: ...n or 0 if the SYNC output is off Default value is 0 OUTPut SYNC SOURce BIT LCOMplete Purpose This command will select the PXA125 SYNC option BIT will set the SYNC to output a narrow pulse LCOMplete will set the SYNC to transition high at the beginning of the sequence and low a the end of the sequence Parameter type Discrete OUTPut SYNC SOURce Response and default The PXA125 will return BIT or LCOM...

Страница 176: ...is 4 OUTPut TTLTrig N OFF ON 0 1 Purpose The backplane on the PXI chassis has some signals on the P2 connector that allow inter instrument communication and synchronization Among these lines there are some trigger lines STAR trigger and local bus lines There are 8 trigger lines that can serve as source or target Normally these lines are designated as tri state lines The OUTP TTLT N command connect...

Страница 177: ... slot 2 however by making the STAR pin output the instrument can send trigger information that can be interpreted as status information by the STAR module ON or 1 will convert the STAR line to output and will place a SYNC pulse on this line OFF or 0 will set the STAR line output off the Sync pulse removed and the line converted to high impedance tri state Parameter type Discrete OUTPut STAR Respon...

Страница 178: ...nts to operate in multi instrument synchronization mode ON or 1 will set the couple mode on OFF or 0 will set the couple mode off Parameter type Discrete INSTrument COUPle Response and default The PXA125 will return 0 or 1 depending on the present instrument couple setting Default value is 0 INSTrument COUPle MODE MASTer SLAVe Purpose This command will select master and slave instruments in multi ...

Страница 179: ...User Manual PXA125 Programming Reference 4 61 ...

Страница 180: ...Numeric integer only Parameter range phase 0 to n in units of waveform points where n is the size of the active segment The phase offset can be programmed in increments of 4 points INSTrument COUPle PHASe Response to query version The PXA125 will return the present phase offset value Default value is 0 INSTrument SET 0 1 2 Purpose This command will prepare the master and slave units for multi inst...

Страница 181: ... number from 0 to n modules can be placed between the master and the slave modules After you have your master and slave units in place you ll have to execute a series of commands to prepare the instruments to their final lock position The following example assumes three adjacent instruments As was explained before the left instrument is called master the center instrument is called slave and the i...

Страница 182: ...mplitude and offset 5 Modifying sample clock frequency In the following you ll find a list of operation that will interfere with synchronization 1 Changing waveform type fix user sequence 2 Downloading waveforms 3 Modifying sync position and width 4 Modifying trigger burst count phase and advance source 5 Modifying phase offset between instruments 6 Modifying frequency setting in fixed waveforms m...

Страница 183: ... Limit High Limit ARM OFF ON 0 1 ON SLOPe POSitive NEGative POSitive BREakpoint POSition position 0 0 n INITiate CONTinuous OFF ON 0 1 ON TRIGger BURSt OFF ON 0 1 OFF COUNt count 1 1 128K GATE OFF ON 0 1 OFF PHASe phase 0 0 n SLOPe POSitive NEGative POSitive SOURce ADVance EXTernal INTernal TTLTrig0 7 STAR EXTernal STAR OFF ON 0 1 OFF TIMer interval 1e3 100e 3 5e6 IMMediate TRG ARM OFF ON 0 1 Purp...

Страница 184: ...on Parameter type Numeric integer only Parameter range position 0 to n in units of waveform points where n is the size of the active segment The breakpoint position can be programmed in increments of 4 points minimum ARM BREakpoint POSition Response and default The PXA125 will return the present breakpoint value Default value is 0 INITiate CONTinuous OFF ON 0 1 Purpose This command will set the ou...

Страница 185: ... COUNt count Purpose This command will set the burst counter count will set the count number Parameter type Numeric integer only Parameter range count 1 to 128K TRIGger COUNt Response and default The PXA125 will return the present count value Default value is 1 TRIGger GATE OFF ON 0 1 Purpose This command will set the gate mode This command will affect the PXA125 only after it will be set to inter...

Страница 186: ...User Manual PXA125 Programming Reference 4 68 ...

Страница 187: ...be selected as an advance source EXTernal will select the external input INTernal will select the internal trigger generator N can be selected from 0 through 7 STAR will select the STAR trigger module Select this option only if you have a STAR module in your system Parameter type Discrete TRIGger SOURce ADVance Response and default The PXA125 will return EXT INT TTLT N or STAR depending on the pre...

Страница 188: ...igger generator Parameter type Numeric Parameter range interval 100e 3 to 5e6 in units of seconds TRIGger TIMer Response and default The PXA125 will return the present internal trigger timer value The returned value will be in standard scientific format for example 10ms would be returned as 10E 3 positive numbers are unsigned Default value is 1e3 TRIGger IMMediate Purpose This command will stimula...

Страница 189: ...e DELete ALL Arbitrary Waveforms Arbitrary waveforms are generated from digital data points which are stored in memory Each data point has a vertical resolution of 14 bits 16384 points i e each sample is placed on the vertical axis with a precision of 1 16384 The Model PXA125 has the following waveform memory capacity 2 Meg standard memory configuration Each horizontal point has a unique address t...

Страница 190: ...ntire waveform to the instrument On the other hand if you are writing your own application you ll need to use the SendComand and SendBlock functions Information on these functions is given at the beginning of this chapter You can follow the general guidelines below to download waveforms to the instrument The following example assumes segment 1 having 1000 points 1 Use the function SendCommand to p...

Страница 191: ... segment The memory space that is being freed will be available for new waveforms as long as the new waveform is equal or smaller in size then the deleted segment If the deleted segment is the last segment then the size of another waveform written to the same segment is not limited For example let consider two segments the first being a 1000 point waveform and the second with 100 points If you del...

Страница 192: ...uenced Waveforms Sequenced waveforms are made of a number of arbitrary waveforms which can be linked and looped in user programmable order Sequenced waveforms are generated from waveforms stored in the PXA125 as memory segments Therefore before a sequence can be used download waveform segments to the arbitrary memory using TRAC or DMA methods Information on how to partition the memory and how to d...

Страница 193: ...User Manual PXA125 Programming Reference 4 75 ...

Страница 194: ... the programmed loops will the sequence step to the next assigned segment MIXed mode is a special mode which combines continuous step advance with single step advance in a sequence There are three conditions for the sequence generator to operate in this mode 1 The PXA125 must be set to operate in continuous mode 2 Select the MIX sequence advance mode 3 Assign the mixed mode bits for each sequence ...

Страница 195: ...1 no loops mode 0 SEQ DEF 2 2 1 1 Step 2 segment 2 no loops mode 1 SEQ DEF 3 3 10 1 Step 3 segment 3 10 loops mode 1 SEQ DEF 4 4 1 0 Step 4 segment 4 no loops mode 0 After selecting the sequence mode the generator will generate segment 1 and automatically advance to segment 2 It will continue to generate segment 2 until a valid trigger is received After it has received a trigger the generator will...

Страница 196: ...nual SYSTem VERSion Purpose This query will interrogate the PXA125 for SCPI version Response to query The PXA125 will return 1999 0 SYSTem IDENtification Purpose This query will return instrument identification Response to query The PXA125 will return a string similar to this one 0x1570 0x500 0000000278 The first field is the vendor ID the second is the device ID and the last field the serial numb...

Страница 197: ... a decimal value which corresponds to the binary weighted sum of all bits set in the register IDN Query the generator s identity The returned data is organized into four fields separated by commas The generator responds with its manufacturer and model number in the first two fields and may also report its serial number and options in fields three and four If the latter information is not available...

Страница 198: ...egisters The Model PXA125 uses the Status Byte register group and the Standard Event register group to record various instrument conditions Figure 4 1 shows the SCPI status system An Event Register is a read only register that reports defined conditions within the generator Bits in an event register are latched When an event bit is set subsequent state changes are ignored Bits in an event register...

Страница 199: ...ue is empty The MAV summary message is true when the output queue is not empty This message is used to synchronize information exchange with the controller The controller can for example send a query command to the device and then wait for MAV to become true If an application program begins a read operation of the output queue without first checking for MAV all system bus activity is held up until...

Страница 200: ...ror Device Dependent Error Execution Error Command Error User Request Power On Standard Event Status Register ESR 6 7 3 2 1 0 6 7 5 4 3 2 1 0 Logical OR RQS MSS ESB MAV Service Request Generation Standard Event Status Register ESE value ESE read by Serial Poll Status Byte Register read by STB Service Request Enable Register SRE value SRE Output Queue Queue Not Empty ...

Страница 201: ...ry weighted values of the Status Byte Register The STB common query does not alter the status byte Clearing the Status Byte Register Removing the reasons for service from Auxiliary Status registers can clear the entire Status Byte register Sending the CLS command to the device after a SCPI command terminator and before a Query clears the Standard Event Status Register and clears the output queue o...

Страница 202: ...of the binary weighted value of the Service Request Enable Register The value of the unused bit 6 is always zero The Service Request Enable Register is written using the SRE command followed by a decimal value representing the bit values of the Register A bit value of 1 indicates an enabled condition Consequently a bit value of zero indicates a disabled condition The Service Request Enable Registe...

Страница 203: ... This bit operation is disabled on the Model PXA125 Bit 2 Query Error This bit indicates that an attempt is being made to read data from the output queue when no output is either present or pending Bit 3 Device Dependent Error This bit is set when an error in a device function occurs For example the following command will cause a DDE error VOLTage 5 VOLTage OFFSet 2 Both of the above parameters ar...

Страница 204: ... ESE Common query The response to this query is a number that represents the sum of the binary weighted value of the Standard Event Status Enable Register The Standard Event Status Enable Register is written using the ESE command followed by a decimal value representing the bit values of the Register A bit value one indicates an enabled condition Consequently a bit value of zero indicates a disabl...

Страница 205: ...nd to read the error queue SYSTem ERRor Errors have the following format the error string may contain up to 80 characters 102 Syntax error A complete listing of the errors that can be detected by the generator is given below 100 Command error When the generator cannot detect more specific errors this is the generic syntax error used 101 Invalid Character A syntactic element contains a character wh...

Страница 206: ...in sine waveform or activating the built in sine waveform when one of the PXA125 filters is turned on Corrective action If in sine select another function and activate the filter s 4 Activating burst mode when the PXA125 is set to sequence mode or activating sequence mode when the PXA125 is set to burst mode Corrective action Remove the PXA125 from burst or sequence and then selected the desired m...

Страница 207: ...ueue Overflow The error queue is full because more than 30 errors have occurred No additional errors are stored until the errors from the queue are removed The error queue is cleared when power has been shut off or after a CLS command has been executed 410 Query INTERRUPTED A command was received which sends data to the output buffer but the output buffer contained data from a previous command the...

Страница 208: ...User Manual PXA125 Programming Reference 4 90 This page intentionally left blank ...

Страница 209: ...ple Clock but limited to 80 Ms s Initial Skew 20 ns to the first master 20 ns cumulative to additional slaves Phase Offset Between Instruments Programmable from 0 to n points SAMPLE CLOCK Range 100 mS s to 125 MS s Resolution 10 digits limited by 1 µHz Accuracy Same as reference StabilitySame as reference Reference Internal System clock 0 01 100 ppm initial tolerance over a 19 C to 29 C temperatur...

Страница 210: ... to 100 KHz Resolution 10 digits Accuracy 0 1 Peak Frequency Deviation DC to 50 MHz Advance Automatic triggered gated or software command Marker Output and Level Same as SYNC output Position Fixed at carrier frequency FM Downloaded Arbitrary Waveforms Description Sample clock can be frequency modulate arbitrary waveforms that are downloaded by the user Modulation Source User waveform any shape 10 ...

Страница 211: ... level hop frequency Frequency Range From 10 MHz to DC Internal Same as internal trigger range FSK Delay Minimum 1 waveform cycle 50 ns Ramped FSK Description Same as FSK except carrier sample clock ramps to shifted frequency at a rate defined by the ramp time parameter TTL low level programs carrier sample clock TTL high level programs shifted frequency Ramp Time Range 10 µs to 1 s 3 digits 0 1 S...

Страница 212: ...rmal Continuous waveform is generated Triggered Each input cycle generates a single output cycle Gated External signal enables generator First output cycle synchronous with the active slope of the triggering signal Last cycle of output waveform always com pleted External Burst Preset number of up to 128K cycles stimulated by an internal or external trigger This mode is not available in Sequence mo...

Страница 213: ...ccuracy 0 01 Software SCPI command Backplane TTLTrig0 through TTLTrig7 STAR System Delay Trigger to waveform output 1 Sample Clock 120 ns STANDARD WAVEFORMS LIBRARY Waveforms Sine Triangle Square Pulse Ramp Sinc Gaussian Pulse Exponential de cay Rise Pulse Noise DC Frequency Range Waveform dependent ARBITRARY WAVEFORMS Waveform Memory 2 Meg points Memory Segmentation Number of Segments 1 to 4096 M...

Страница 214: ...ision of the memory bank into smaller segments Segments may be linked and repeated in user selectable fashion to generate extremely long waveforms Advance Modes Automatic Sequence Advance No triggers required to step from one segment to the next Sequence is repeated continuously through a pre programmed sequence list table Stepped Sequence Advance Current segment is sampled continuously external t...

Страница 215: ... open circuit Resolution 3 5 digits Accuracy 1 KHz 800 mV to 8 Vp p 1 10 mV 80 mV to 799 9 mVp p 1 1 mV Offset Offset Offset is attenuated with amplitude Range 0 to 3 6 V amplitude dependent Resolution 22 mV Accuracy 4 V window 1 of reading 1 of amplitude 2 mV 400 mV window 1 of reading 1 of amplitude 200 µV Filters 25MHz and 50 MHz 7 pole elliptic Square Wave Pulse Rise Fall time 10 ns 10 to 90 o...

Страница 216: ...tion BIT Generates a sync signal each time a point within a specific wave segment is accessed LCOM Loop Complete Generates a single SYNC signal Starts at a begin ning of a sequence and ends at the end of the sequence Impedance 50Ω 1 Level 2 V into 50Ω 4V nominal into 10KΩ Protection Protected against temporary short to case ground Position Point 0 to n Programmable with 4 point resolution Width Pr...

Страница 217: ...dBc to 100 MHz INPUTS TRIG Input Connector Front panel BNC Impedance 10 KΩ 5 Threshold LevelTTL Damage Level 10 V Min Pulse Width 20 ns Slope Positive or negative going edge 10 MHz Reference Input Connector Front panel SMB Impedance 10 KΩ 5 Threshold LevelTTL Damage Level 10 V Duty Cycle 50 5 GENERAL Power Requirements 10W maximum Current Consumption 5 V 30 mA 12 V 200 mA ...

Страница 218: ...ature Operating 0 to 50o C Temperature Non Operating 40 to 71o C Humidity non condensing 5 to 95 RH at or below 30o C Upper limit derates to 75 RH above 30o C and 45 RH above 40o C Certifications CE Marked EMC Conforms to EN 61326 1 1998 Safety Conforms to EN 61010 1 2001 Workmanship Standards Conforms to IPC A 610D ...

Страница 219: ...User Manual PXA125 Specifications A 101 This page intentionally left blank ...

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