Keithley 194 User Manual Download

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Summary of Contents for 194

Page 1: ...Instruction Manual Model 194 High Speed Voltmeter 01985 Keithley Instruments Inc Instrument Division Cleveland Ohio U S A Document Number 194 901 01 Rev A...

Page 2: ...azardous voltage is present in any unknown circuit before measurement Do not exceed 3OV RMS between input low and earth ground Inspect your test leads for possible wear cracks or breaks before coach u...

Page 3: ...1 8 bitmod In samples are stored prior to triggering Past Trigger 1 n 1x 10 Storage begins n samples after tri gWi g TRIGGER SOURCE DESCRlPTlON Input Signal Slope or Level Selectable over input volta...

Page 4: ...ATE 90k bytesisecond DISPLAY Fourteen digit alphanumeric LED display Function and IEEE bus status also displayed RANGING Manual or autoranging WARMUP One hour to rated accuracy OPERATING ENVIRONMENT 0...

Page 5: ...onnecting the Model 194 to the IEEE 488 bus and programming the instru ment from a computer SECTION 4 IEEE 488 Programming Outlines procedures necessary to verify that the in SECTION 5 i strument is o...

Page 6: ...2 2 FRONT PANEL FAMILIARIZATION 2 l 2 2 1 Controls 2 1 2 2 2 Display 2 8 2 2 3 IEEE 488 Status Indicators 2 Y 2 2 4 TiltBail 2 Y 2 3 REAR PANEL FAMILIARIZATION 2 Y 2 4 POWERUPPROCEDURE 2 12 2 4 1 Pow...

Page 7: ...DLJALCHANNEI OPERATION 3 16 Channel 2 Connections 3 16 Channel Selection 3 16 Speed Considerations 3 17 Cross Channel Triggering 3 17 USING ZERO 3 17 Zeroing From an Applied Signal 3 18 Keying In the...

Page 8: ...ERATION 4 I BUS CONNECTIONS 1 3 INTERFACE FUNCTION CODES J 6 PRIMARY ADDRESS SELECTION 4 h CONTROLLER PROGRAMMING 4 7 LunIrOlier tlanaier sorrware t i BASIC Interface Programming Statements 4 i Model...

Page 9: ...4 6 4 1 6 4 2 6 4 3 6 4 4 6 4 5 6 5 6 5 1 6 5 2 6 5 3 6 5 4 6 5 5 6 5 6 6 5 7 6 5 8 6 5 9 6 6 6 6 1 6 6 2 6 6 3 6 6 4 6 6 5 6 6 6 6 6 7 6 6 8 5 l 5 l 5 2 5 2 5 3 5 3 5 5 5 6 INTRODUCTION 6 l FUNCTION...

Page 10: ...7 2 OPTION INSTALLATION 7 2 Installation Procedures 7 2 Module Recognition Programming 7 6 CALIBRATION 7 h Recommended Calibration Equipment 7 h Environmental Conditions 7 0 Warm up Period 7 i Front P...

Page 11: ...ION 8 l 8 5 FACTORY SERVICE 8 l 8 6 COMPONENT LOCATION DRAWINGS AND SCHEMATIC DIAGRAMS 8 l APPENDICES AI PENDIXA A l APPENDIX B B l APPENDIX C C l APPENDIX D D l APPENDIX E E l AI PENDIX F F l APPENDI...

Page 12: ...ar Panel Showing Channel 2 Installed 3 16 Typical Filter Response Curves 3 20 Rear Panel Showing ANALOG OUTPUT Jacks 3 21 Typical Plotter Connections 3 21 Typical Oscilloscope Connections 3 22 Typical...

Page 13: ...4 A D Converter Timing 6 7 6 5 Digital Control Block Diagram h 10 6 6 Microcomputer Block Diagram h 15 6 7 Memory Map 6 17 h 8 110BlockDiagram h 20 6 9 Power Supply Block Diagram h 22 6 10 Display Bo...

Page 14: ...m Dwg No 194 116 8 21 8 6 A D Board Component Location Drawing Dwg No 194 120 8 30 8 7 A D Board Schematic Diagram Dwg No 194 126 8 31 8 8 I O Board Component Location Drawing Dwg No 194 160 8 42 8 9...

Page 15: ...37 3 16 Synchronizing Five Units by Daisy Chaining 3 38 3 17 Voltage and Percent Error For Various Time Constants 3 45 SECTION 4 IEEE 488 PROGRAMMING 4 l 4 2 4 3 4 4 4 5 4 6 4 7 4 8 4 9 4 10 4 11 4 12...

Page 16: ...7 2 7 3 7 4 7 s 7 6 7 7 7 8 7 9 7 10 7 11 F 12 7 13 7 14 7 15 7 16 7 17 Line Voltage Selection 7 2 Line Fuse Selection 7 2 Recommended Calibration Equipment 7 7 Calibration Surnmary 7 7 AC Response Ad...

Page 17: ...S G l G 2 G 3 G 4 G S IEEE 488 Bus Command Summary G 3 Hexadecimal and Decimal Command Codes G 7 Typical Addressed Command Sequence G 7 G 7 Typical Device Dependent Command Sequence IEEE Command Group...

Page 18: ...MS peak and peak to peak arc included with the in strument software l Dual channel Operation Two separate isolated AID channels are available with the optional Model 1944AiD Module installed l IEEE 48...

Page 19: ...s The resolution figures given in the specifications are de rived by dividing the full scale displayable range by the number of steps for that particular converter resolution For example in the lh bit...

Page 20: ...that you can measure many sources the input terminals of the input amplifier by shorting the that are not referenced to power line ground The 30V RMS high and low terminals of the input amplifier toge...

Page 21: ...apid rise and fall times Slew rate and set tling time are discussed elsewhere in this section Basic DC accuracy is specified as percent of reading an offset Since the offset on a given range is consta...

Page 22: ...bed in Section 4 1 9 REPACKING FOR SHIPMENT Before shipment the instrument should be repacked in its original shipping carton If the instrument is to be returned to Keithley Instruments for repair inc...

Page 23: ...d Readings Defines these terms as used in this manual 2 2 FRONT PANEL FAMILIARIZATION An overview of the Model 194is given in the following paragraphs The front panel of the instrument is shown in Fig...

Page 24: ...GETTING STARTED Figure 2 1 Model 194 Front Panel 2 2...

Page 25: ...r interval between samples Cancel IEEE 488 remote status restore front panel operation return display to normal Select channels 1 or 2 dual channel display or scanner channels Enable disable autorangi...

Page 26: ...mode allows the baseline value used with the zero mode to be viewed or entered from the front panel by using the data entry keys 0 3 FILTER The FILTER button selects 50kHz or 500kHz single pole analog...

Page 27: ...to the horizontal axis on plots XY ZOOM works in conjunction with XY PAN to sweep and expand areas of interest or to get an overall view of collected data 0 0 SCAN The SCAN kev is intended for use wit...

Page 28: ...number of functions to move the instrument down one range each time it is pressed to move the display cursor ti the left in the data entry mode to decre ment the scaling factor in the XV zoom mode to...

Page 29: ...Z Samples O l C Samples O l seC P v F v PV 05 CHi CH2 This key programs the instrument to display the ratio of the channel 1 reading to the channel 2 reading It is operational only if the Model 1944 o...

Page 30: ...e Model 194 display consists of fourteen 14 segment LED display units The display shows not only instrument readings but in many cases messages to augment the __ various operating modes The general di...

Page 31: ...dual channel display format Note that channel numbers are not displayed in this mode 1 2345 2 5902 Note that channel 1 appears on the left in the dual chan nel mode NOTE A decimal point between the s...

Page 32: ...GETTINGSTARTED Figure 2 5 Model 194 Rear Panel 2 10...

Page 33: ...rument 0 43 REAL TIME OUTPUT This DB 25 connector i used to transmit A D data in byte or word parallel form to other equipment such as a computer Data can be transmitted at the programmed sample rate...

Page 34: ...ower is applied through the sup plied 3 wire power cord to the AC receptacle The operating voltage is marked on a label adjacent to the rear panel If necessary the operating voltage can be changed as...

Page 35: ...occurs the unit will display a CAN T IDENTIFY error message for the appropriate channel In this case it will be necessary to program module recognition as described in paragraph 7 4 2 Following this...

Page 36: ...measurement range 32OmV 3 W 32V or ZOOV or press AUTO and let the instrument choose the best range for the applied signal Step 3 Program the Sampling Rate Press RATE followed by the desired data entry...

Page 37: ...nt to select the best range Connect a suitable BNC cable to the VOLTAGE INPUT jack for the selected channel Connect the other end of the cable to the voltage source to be measured as shown in Figure 2...

Page 38: ...uence is performed a reading can be generated by processing the block of samples in s me way For example to obtain the true RMS value of the measurement remember a measurement is a series of samples y...

Page 39: ...g For d synumctrical sine vInr i 40kHz should be chosen coupling could be used to removt JIIY SIIUII DC uffwt that might be present in thr wa wfo m 3 The programmed number of samples will depend on th...

Page 40: ...tion Gives important operating information on using a Model 194 that is equipped with the optional Model 1944 Module in the channel 2 location 3 10 Using Zero Describes how t USCthe ZC T mode in cludi...

Page 41: ...iously selected Future option of the Model 194 NOTE 3 3 RANGE SELECTION A separate trigger will still be required for each range change except in the continuous front panel mode The Model 194 has four...

Page 42: ...by using the RECALL button When the instrument is in the continuous trigger and autorange mode it continuously samples the signal at the selected rate and attempts to choose the best range based on t...

Page 43: ...ata entry pro cess to cancel data previously entered into the display with 3 4 the data entry keys When CANCEL is pressed the display will return to the previous value If no cursor or data en try keys...

Page 44: ...displays the NMBR TOO SMALL error message and then returns to the previous ly programmed value Example 4 Demonstrating the use of the CANCEL key 1 Press RATE to enter the sample entry mode Note that...

Page 45: ...2 Program a 1OOkHz rate 1 Press RATE to enter the rate entry mode The unit will then display the programmed value 2 Press FREQITIME if necessary to display time inter val information If the instrument...

Page 46: ...as in this example 7200 SAMPLES In this case 1200 samples are to be taken during the measurement sequence Example 1 Program 750 samples 1 Press the SAMPLES key The unit will then display the presently...

Page 47: ...n the samples mode 3 5 3 Samples and Rate Selection Considerations Because the Model 194 can sample input signals at rates as high as lMHz it is ideal for many applications involv ing the analysis of...

Page 48: ...d be aware that such harmonics do exist From this discussion we can see that it may necessary to choose a sampling frequency substantially above the fun damental frequency of a non sinusoidal waveform...

Page 49: ...ent is in the immediate TRIGGER button continuous mode it will process measurements con tinuously without requiring additional triggers 2 If the selected trigger source is the input signal exter nal t...

Page 50: ...l Under these conditions the instrument will automatically adjust the entered delay to the nearest valid value Whether delay is entered in time or sample units the ill strument will remember which uni...

Page 51: ...curs and the trigger point is assumed to be the same as the first buffer sample However if the delay parameter is non zero the first sam ple location will be moved in accordance with the pro grammed d...

Page 52: ...ing the LEVEL key 7 his teature applies cmly when In B a similar situation exists except that the unit is non the selected trigger source is the input signal When LEVEL programmed for a negative slope...

Page 53: ...and cannot be floated NOTE Shielded cable should be used for TRIGGER signal connections to minimize the possibility of EM1 radiation Whenever the instrument is triggered it will generate an output pu...

Page 54: ...ode the samples in the various buffer Iocd tions may or may not be changing as you access thenl In the single trigger mode the samples will be updated ml when the instrument is triggered In the contin...

Page 55: ...identical to those for CARD 1 The purpose of each connector is briefly described below The paragraph where more detailed information may be found is also indicated Figure 3 5 Rear Panel Showing Channe...

Page 56: ...is to be triggered by a positive going input signal at a threshold of 4 6V 1 Using the CHANNEL button select the channel 2 display mode 2 Press the SOURCE button and then uprange or downrange repeated...

Page 57: ...ropriate emv message Also the instrument will display a NMBR TOO SMALL error if you attempt to pro gram a zero value smaller than the resolution of the AID converter 1OpV As with the ZERO key ZERO VAI...

Page 58: ...ther the 50kHz or 500kHz filters are enabl ed the FILTER indicator will be on To return to the previous mode press FILTER a second time Table 3 5 Filter Display Messages Message FILTER OFF FILTER 500K...

Page 59: ...Figure 3 6 Typical Filter Response Curves 3 20...

Page 60: ...a minus full range input while the maximum Y output is equal to a plus full range input For example on the 32OmV range a 327 68mV input voltage will yield a Y output value of approximately OV while a...

Page 61: ...time will return the unit to the previous mode Table 3 7 XY Mode Display Messages 1 F I I Y DATA YY ZOOM ZY PAN XY CRT XY SCOPE XY SLOW PLOT XY STRIP CHT MEASMNT BUFFER MEASMNT RAM READINGS IEEE 488...

Page 62: ...nge or downrange until the appropriate message is displayed Table 3 7 The displayed data source is placed into effect immediate Press XY DATA again to return to the previous mode Available data source...

Page 63: ...ed in the output would be N With 900 samples the number of samples reflected in the output would be 90011 41642 Program a scaling factor by using the following procedure 1 Press SHIFT XY ZOOM The inst...

Page 64: ...ese condi tions samples 100 199will be transmitted out the analog output assuming a scaling factor of 1 2 To change the value key in the new digits vith the numeric keys and press ENTER v increment or...

Page 65: ...OPERATION Figure 3 12 Moving Analog Output Viewed Data with XY PAN 3 26...

Page 66: ...ke sequences and display messages for each of these programming modes OTHER BUTTON X Output Level Programming The full scale X output can be programmed to values between 1 and 1OV with 1pV resolution...

Page 67: ...nrange key to toggle the display between LOW and HIGH levels 3 The blanking level is placed into effect immediately 4 Press CHANNEL to return to previous mode Discussion Figure 3 13 demonstrates the o...

Page 68: ...on will cancel the previously selected function It is not possible for example to take the integral of the standard deviation Once a function is selected you can perform that particular function a num...

Page 69: ...mples 11 Thus the average of this measurement would be v l30 65111 VrlVG 11 877V 3 13 2 True RMS The true RMS value of a voltage waveform is that value which would produce the same heating effect as a...

Page 70: ...umber 3 which has an amplitude f 14 25V The most negative least positive sample is number 10 with a signal level of 1OV 3 13 4 Peak to Peak The peak to peak value of the selected channel can bc displa...

Page 71: ...f not in data entry mode will display the integral of the measurement in volt seconds A typical display in the in tegral mode might be 4 0315EOOl VS 2 In this case the integral of the channel 2 measur...

Page 72: ...sed in the following paragraphs RATIO DIFFERENCE BUTTONS Display messages associated with these modes are sum marized in Table 3 11 Note that the instrument displays the following message if one of th...

Page 73: ...and in cludes an exponent along with appropriate units Any previously selected mathematical operations will be performed before the division process is completed When in the waveform mode the instrume...

Page 74: ...KJP will result in a smirWI IICI I message At this point you should use the Cl IAN NEL key to select which channel to recdll Table 3 13 Setup Mode Display Messages 1 Message Description RECALL SETUP n...

Page 75: ...HER key arc covered in detail in appropriate paragraphs of this manual as follows CAN T STORE 0 Program 0 IEEE 488 address paragraph 4 5 Program 1 self test paragraph 7 8 Programs 2 and 3 digital cali...

Page 76: ...EM1 radiation Figure 3 15 Synchronous Operation Up to 16 units may be daisy chained together by tlsing the same basic connecting scheme Figurr 3 16shows five such units connected together one master a...

Page 77: ...ogram a 1OOkHz sampling rate transmission will occur at that frequency 3 20 1 Signal Lines The pin out diagram for the real time connector is shown in Figure 3 17 Signal lines are listed in Table 3 16...

Page 78: ...rds will have been lost under these conditions MEASURING This line will be high when the instrument is performing a measurement sequence in other vords the triggering condition has been met 3 20 2 Rea...

Page 79: ...side of the diagram typical computer bus lines are shown including the data bus DO D7 the address bus as well as bus clock and reset lines The interface itself is shown in the center part of the diag...

Page 80: ...OPERATION r Figure 3 20 Simplified Block Diagram of Real Time Computer Interface 1 3 41...

Page 81: ...go about accessing real time data and storing it in computer memory The program accesses 256 bytes 128 words of instrument data and stores them in a memory buffer beginning at location COOO SOURCE COD...

Page 82: ...the wires will encounter small resistances either in the wires or at the connecting points This small resistance results in voltage drops that can affect the measurement Even if the ground loop curre...

Page 83: ...source voltage and source resistance respectively the instrument input resistance is RI and the voltage seen by the meter is VM r l ifi Ir 1 I I L _ J r l r r 1 1 iFT Q IRI IRI I VM I VM I I L _ J L...

Page 84: ...input capacitance does increase response time it can help to filter out some of the higher frequency noise present in the signal by effectively limiting instrument bandwidth If we assume that all inpu...

Page 85: ...lications for the Model 194 High Speed Voltmeter Keep in mind that these examples are only representative of Model 194 capabilities and by no means even begin to ex haust the possible uses for the uni...

Page 86: ...ry however as it is generally difficult if not impossible to view such waveforms on an ordinary oscilloscope The Model 194 however can give you digital storage oscilloscope capabilities when used with...

Page 87: ...could be programmed for appropriate rate samples and trigger mode With the periodic waveform a rapid sampl ing rate would probably be required while a much slower rate would be required for long term...

Page 88: ...take is 15 000 since the instru Assume we wish to analyze the fall time of a typical pulse ment can sample at rates up to IMHz Above lOOkHz like the one shown in Figure 3 29 This pulse has a peak how...

Page 89: ...interval is 1Opsec 100kHz sampling frequency The fall time under these conditions is tf 900 150 x 10 x lo 6 tf Z5msec 3 22 6 Reducing Noise in the Measured Signal Very often 50 or 6OHz noise can cree...

Page 90: ...Vibration Testing Most equipment manufacturers perform some sort of vibration tests on their equipment in order to get some idea as to how well it will hold up in the real word As with any test proced...

Page 91: ...Aspects of IEEE 488 Operation Describes the operation of the LOCAL key and bus status indicators and summarizes front panel messages that may occur during bus operation General Bus Command Programming...

Page 92: ...mands to the Model 194 and display the data string on the computer CRT Model 8573 Programming Example Add the lines below to the modified declaration file see Model 8573 lnstruc tion Manual or paragra...

Page 93: ...ach command In other cases you may wish to program the instrument configuration at the beginning of your program and then obtain a whole series of measurements The basic reading string that the Model...

Page 94: ...m To Continuous talk Tl Single talk T2 Continuous GET l 3 Single GET T4 Continuous X T5 Single X T6 Continuous external T7 Single external T20 m Continuous Slope using trigger level m volts T21 m Sin...

Page 95: ...imum of 15 devices including the controller The maximum cable length is 20 meters or 2 meters times the number of devices which ever is less Failure to observe these limits may result i erratic bus op...

Page 96: ...Unaddressed To Talk On MLA L4 Listener Basic Listener Unaddressed To Listen On MTA SRl Service Request Capability RLI Remote Local Capability PPO No Parallel Poll Capability DC1 Device Clear Capabili...

Page 97: ...ith the Model 8573 interface interface programming may depend on the particular in terface being used Many times little tricks xc necessaw to obtain the desired results 4 6 2 BASIC Interface Programmi...

Page 98: ...37 I fi L L 1 y F 1 I 1 I A i I 1 ii I I 13 1 1 fi zi bI E S 11 LL IE FI D q p j q I l j l I j 1fi pti 1 I p 1 4 I 4 Now save the modified declaration file for use with the programming examples in thi...

Page 99: ...he instrument will brief ly display the following error message IDDC To correct the error condition send only valid commands Refer to paragraph 4 9 for device dependent command programming details HP...

Page 100: ...rument is in the remote mode Note that REMOTE does not necessarily indicate the state of the REN line as the instrument must be addressed to listen with REN true before the REMOTE indicator will turn...

Page 101: ...t LQCAL will be inoperative Normal front panel operation can be restored by pressing the LOCAL key To place the Model 194 in the remote mode the controller must perform the following sequence 1 Set th...

Page 102: ...nter the following statement into the IBM PC 1 11 ii I Ei I 1 8 E F 1 I After the return key is pressed the instrument will return to the talker idle state 4 8 3 LLO Local Lockout The LLO command is u...

Page 103: ...4 8 5 DCL Device Clear The DCL command may be used to clear the Model 194 and return the unit to default conditions Essentially this command will perform the same function as the front NOTE The prima...

Page 104: ...is executed the instrument returns to the default configuration Model 8573 Programming Example Alter instrument con figuration with several front panel controls and enter the following statements into...

Page 105: ...oll the Model 194 from the IBM PC computer as follows When the statements above are cxccutcd the instrument is serial polled and the decimal value of the status byte is displayed on the computer CRT 4...

Page 106: ...out the necessary separating comma or other legal delimiter The list below details which device dependent commands will generate the IDDCO error message and those com mands which incorporate auto boun...

Page 107: ...cm slE6 NO m Take m samples per measurement 1 m 65 535 Nl m Measurement duration m set 0 5 m 5 65 534 lo Continuous talk n Single talk T2 Continuous GET l 3 Single GET T4 Continuous X T5 Single X T6...

Page 108: ...le Voltage 1zs ls10 O5 m m Y Output Full Scale Voltage 151 510 06 m Z Output Blanking Level l High O Low 07 l m XY Zoom Value O lrm 1000 08 m m XY Pan Value O rn565 536 09 start Plotter iuffer Pointer...

Page 109: ...s LIST SRQ disabled 3verflow Data condition Button pressed Reading done Ready to accept commands Error Channel 1 A D module Channel 2 Select composite channel no parameter changes allowed EOI and hold...

Page 110: ...rams in paragraph 4 2 4 9 1 Execute X The execute command is implemented by sending an ASCII X over the bus Its purpose is to direct the Model 194 to execute other device dependent commands such as F...

Page 111: ...average of the samples in the measurement buffer Note that the instrument displays the average of the samples after the return key is pressed the second time 4 9 3 Range R The range command and its o...

Page 112: ...e follow ing statements to program a sampling rate of 100 sec 4 9 5 Number of Samples N The N command allows you to program the number of samples to be taken during a measurement sequence or in measur...

Page 113: ...he AID converter is automatically re armed after each measurement Thus in this situation the triaer nwde command would only bc required once Regardless of whether the single r cc ntinuous nxrdt is use...

Page 114: ...ignal drops to a level programmed by the m parameter Again m is given in volts Other Channel T24 and T25 Triggering takes place when the other channel is triggered The method used to trig ger the othe...

Page 115: ...hat the range of the pre trigger varia tion is much smaller than that of the post trigger mode W0 k m The delay period is programmed in samples Wl m The delay period is programmed in sec Upon power up...

Page 116: ...fix control The prefix indicates the type of measure ment as discussed below Various modes omit the prefix as summarized in Table 4 15 4 Suffix control The suffix shows the channel number and buffer l...

Page 117: ...m measurements in G6 When requesting waveform measurements in G6 or G7 data formats raw binary data in offset binaq or G7 data formats raw binary data in offset binaq will be sent In any other functio...

Page 118: ...IN S BIT MODE RANGE CHANNEL FUNCTION DECIMAL BINARY DECIMAL BINARY 0 0000 32Ol 3 0001 1 0 0000 WAVEFORM 1 0001 3 2V 0010 2 1 0001 AVERAGE 2 0010 32 0011 3 2 0010 TRMS 3 0011 200 0100 4 3 0011 PEAK 01...

Page 119: ...the numeric value is placed If the prefix and suffix are not eliminated with the correct G command an incorrect value may be placed into the numeric variable In the G6 and G7 binary modes data bytes c...

Page 120: ...utput full scale value lal lOV Proa am m as Y outout full scale value Y Set m as Z output blanking level l high O low Program m as XY Zoom value O l m 1 000 Program m as XY Pan value O m 64k start Plo...

Page 121: ...st position and ca allow data access from snmplc 0 BOca also be used after changing fmm FO to another function to clear waveform output and alable data output for the selected function If the reading...

Page 122: ...ome available Normally as you ac cess reading buffer data the number of locations left to be accessed in the buffer are transmitted as part of the data string assuming the G2 data format is in effect...

Page 123: ...buffer after each trigger stimulus 3 For dual A D equipped units channel readings will be placed in the next available buffer location as they are completed 4 If the reading buffer is turned on with t...

Page 124: ...mode is covered in more detail in paragraph 3 11 Upon power up or after a DCL or SDC the unit will assume a zero mode determined by the SETUP 1 Al con figuration Factory default is zero disabled ZO C...

Page 125: ...e found on an oscilloscope In this manner these command options operate in the same way as the front panel CPLG key More detailed information on the coupling modes may be found in paragraph 3 7 Table...

Page 126: ...status word for the selected channel the next time it is addressed to talk instead of its normal data string The status word will be transmitted only once each time the UO command is given To make sur...

Page 127: ...2 GROUND COUPLING RECALL SETUP An O FACTORY SETUP I SETUP 1 2 SETUP 2 SAVE Ln l SA E SETUP 1 2 SA t SETUP 2 4 CALIBRATE USING VALUE 5 STORE CAL IN NVRAM READING BUFFER Qn O DISABLED LINEAR WFFER 2 CI...

Page 128: ...illegal Not In Remote Set when a programming command is received when the REN line is false Trigger Overrun Channel l Set when the channel 1 A D converter is triggered when it is not armed Trigger Ove...

Page 129: ...onverter Armed Set when the A D converter is armed and ready to take a measurement Cleared when the A D converter is not armed 8116Bit Mode Indicates whether the A D converter for the selected channel...

Page 130: ...nt is placed in remote line 20 and a loop is set up to request the 12status words line 30 The status word command is then sent to the instrument line 40 and status is then requested and displayed line...

Page 131: ...isplay mode or if a translator error occurs or with a sample or delay conflict 1 I Description SRQ Disabled Rending Overflow Data Buffer full I full ttcr done Front panel button pressed Reading Done R...

Page 132: ...s ready to be sent over the bus Cleared by requesting a reading over the bus Button Pressed bit 2 S when a front panel button has been pressed even if the unit is in remote Cleared when the UO status...

Page 133: ...erate a SRQ line 60 After the SRQ is generated the instru w t is serial polled line 70 and the status bytes are the displayed lines 90 130 Finally the UI error condition word is requested and displaye...

Page 134: ...ff on X disabled upon power up or after a DCL or SDC command the KO mode will be enabled EOI End or Identify The EOI line on the IEEE 488 bus provides one method to positively identify the last byte i...

Page 135: ...owed by sending the ASCII value or values of the desired terminator or terminators Table 4 V ASCII values may be found in Appendix A The default ter minator sequence is the commonly used carriage retu...

Page 136: ...red channel programming its various operating modes and then using the desired save command option Table 4 29 summarizes those instrument operating modes that can be saved in this manner Once saved th...

Page 137: ...e as AO Table 4 30 Recall Commands HP 85 Programming Example Use the following state ments to recall the setup 1 position for channel 1 Note that the instrument assumts the channel 1operating modes st...

Page 138: ...haracters 14 maximum DX Return display to normal mode LOCAL also returns display to normal mode To send a message to be displayed simply follow the D command with the appropriate ASCII characters Most...

Page 139: ...this point and press the return key After typing in your message note that it is displayed on the front panel of the Model 194 To continue the pro gram press any computer key when prompted to do so 4...

Page 140: ...a string of commands For example the word SAMPLES could be used in place of NO lOOO In a more complex example the word SETUP1 could be used in place of ROFlT3G4 The Translator mode can also be used t...

Page 141: ...ords and device dependent command string A max imum of 1024 bytes are available for Translator memory Each word definition requires a 17 byte overhead plus one byte per letter including the Translator...

Page 142: ...also be used to combine Translator words as discussed in paragraph 4 10 3 Note that using the ALIAS command automatically enables the Translator mode OLD This command disables the Translator mode Aft...

Page 143: ...tor words and not device dependent commands is the terminator that marks the end of the ALIAS sequence s e A space must be included between each Note that the instrument will still recognize any origi...

Page 144: ...T Send LIST corn word list Display Translator words After adding the above lines run the program and note that the Translator words are displayed on the computer CRT HP 85 Programming Example Run the...

Page 145: ...of Samples 101 101 101 1000 1 1000 1 1 1000 1000 1000 1000 1000 1000 Wavefornl TRMS I eeak Peak Peak to peak Standard Deviation Integral Math Function Average Peak to peak Integral Average Average Ave...

Page 146: ...am ming examples for verifying instrument accuracy over the IEEE 488 bus 5 8 AC Frequency Response Lists the procedure for checking the frequency response of the input amplifier 5 2 ENVIRONMENTAL COND...

Page 147: ...erminated with a dual banana jack When making the calibrator connection the cable shield should be connected to the low output ter minal of the DC calibrator CAUTION Maximum input is 250V peak 2 x 107...

Page 148: ...oltages with negative polarity 11 Program a 9 9 sampling interval dnd 101 102 samples repeat the above procedure Use the limits stated in Table 5 2 for the R bit mode 12 If the Model 1944 option is in...

Page 149: ...Cl X Prompt for channel number Input channel n ber 60 IF 1 I ClE1 1 THE 40 If not 1 or 2 go f at Loop for all four Interval samples 16 bit Read verification limits Prompt for veri fication voltage Wai...

Page 150: ...ccuracy using an IBM PC or XT computer equipped with a Keithley Model 8573 IEEE 488 Interface Input channel to be verified If not channel 1 01 2 repeat Build channel command string Select channel I ro...

Page 151: ...inal 52 tolerance and not on stated specifications 1 Connect the AC calibrator Table 5 l to the VOLTAGE INPUT jack of the channel being tested Use the basic connecting scheme shown in Figure 5 3 2 Usi...

Page 152: ...ircuits and power supply circuitry Channel 2 circuitry for thi se instruments outfitted with the optional Modci 1944 A D module is identical to that shown for channel 1 Input signals are applied to th...

Page 153: ...PRINCIPLES OF OPERATION Figure 6 1 Simplified Block Diagram 6 2...

Page 154: ...4 and 1 21 depending on the positions of K303 and K304 From the input coupling cir cuit signals are applied the input attenuator made up of R312 R313 and R 318 Frequency compensation is pcr formed by...

Page 155: ...A D converter itself the data parallel to serial data conversion circuits the opto isolators the con trol serial to parallel converters and the data control circuits The analog input signal is applie...

Page 156: ...UI I I 1...

Page 157: ...ted conversion is indicated by a positive going edge on the EOC line Note that data present on the data terminals is from the previous conversion that is data always runs one conversion behind the tri...

Page 158: ...PRINCIPLES OF OPERATION TRIGGER EOC DATA OUTPUTS x DATA VALID PRE CON 6 7...

Page 159: ...with the next 5MHz clock pulse and applied to the 1D in put of U375 After two clock pulses both inputs of U383C will be high and its output will go low This action causes 6 8 AID converter data to be...

Page 160: ...coils 3 U361 U370 and U383 are used to store digital calibra tion information for the A D converter This informa tion is converted to analog form by two 12 bit DACs LJ362and U363 as previously discuss...

Page 161: ...PRINCIPLES OF OPERATION Figure 6 5 Digital Control Block Diagram 6 10...

Page 162: ...h is loaded the counter is preset from the latch by a control pulse The countdown period is controlled by the 1OMHz clock of the microprocessor or by an external clock pulse if one is applied Since th...

Page 163: ...e sample counter circuits are located on drawing number 194 126 page 3 The sample counter itself is made up of U345 and U346 which are up down binary counters 74LS193 Since each counter is capable of...

Page 164: ...7 U340 Each of these devices is a 64K X 1 bit dynamic RAM 6665A Each IC stores one bit of the 64K bytes of available storage An individual storage element within the IC is actually a vcr small capacit...

Page 165: ...stored in the two NVRAM ICs U301 and U302 2443 These ICs also store identifying informa tion as to the type of module installed in channel 2 loca tion Each device is organized into 16 words of 16bits...

Page 166: ...PRINCIPLES OF OPERATION d I 105 _ 1 1 AID LOCK II Figure 6 6 Microcomputer Block Diagram...

Page 167: ...E This line provides an enable clock to peripheral ICs such as the I IAs and VIAs present in other sections of the instrument CLK The 1OMHz microprocessor clock is applied to this input Valid Peripher...

Page 168: ...A19 address lines and the outputs drive the select cir cuits for the various peripheral and memory segments The corresponding output will go low when a particular 64K segment is selected For example...

Page 169: ...flow from external components to the MPU Since information on the data bus flows in both directions a bidirectional buffer IC must be used UT17 is an octal transceiver IC 74LS645 that provides such ca...

Page 170: ...ich perform many of the interfacing func tions Two PIAs Peripheral Interface Adapter provide the interface to the front panel display These ICs also provide the interface to the NVRAMs located on the...

Page 171: ...PRINCIPLES OF OPERATION I I 1 Figure 6 6 l O Block Diagram 6 20...

Page 172: ...0 during power up setup progamming or calibration constant storage 6 7 5 Analog Output Interfacing Data for the analog outputs are latched at the appropriate times into U4l2 U415 Each of these KS is a...

Page 173: ...AC recep is to be operated from 105 l25V or 210 250Vpower sources tack located on the rear panel of the instrument FlOl is From the primary power is magnetically coupled to the the line fuse which pro...

Page 174: ...ng than normal is required Cl39 L102 and Cl43 make up Bpi filter to attenuate any switch ing noise or ripple at the supply output Supply Protection Three forms of protection are included with the swit...

Page 175: ...e supplies 14 segment displays LED annunciators and switch matrix respectively The supply outputs are further filtered by Both the 14 segment displays and LED annunciators are Cl12 and Cll3 multiplexe...

Page 176: ...n the display are to be turned on Since the segment terminals are connected to the anodes a high logic level must appear on the lines for those segments that are to bc turned on Next the digit select...

Page 177: ...edure for calibrating the Model 194 including recommended calibration cqulpment 2 Locate the line voltage selection s itch adjacc nt t the power transformer on the mother board we t igure 7 l 3 Place...

Page 178: ...rating than specified or instrument damage may occur If the instrument repeatedly blows fuses locate and correct the cause of the trouble before resuming operation of the unit 3 Install the new fuse...

Page 179: ...the cable through the top hole in the l O board 6 Connect the 5 digital supply connector to J1023 or J1024 unused connector on the mother board This connector is polarized and can be installed only i...

Page 180: ...MAINTENANCE Figure 7 l Line Voltage Switch and Digital Supply Fuse Locations 7 4...

Page 181: ...MAINTENANCE Figure 7 2 Model 1944 A D Module installation 7 5...

Page 182: ...he corresponding module may be faulty Refer to the troubleshooting procedures in paragraph 7 8 for further information 5 If A D module recognition was programmed refer to Section 5 for procedures to v...

Page 183: ...calibrator to the value in the first line of Table 7 4 32O OOmV 5 Enter the front panel calibration program by pressing OTHER and using uprange until the DIGITAL CAL message is shown Press ENTER The...

Page 184: ...control the calibrator because various calibrators USC different commands I Iowever if you are using an IEE 4R8 interfaceable calibrator you should be able to modify these programs quite easily to ca...

Page 185: ...e Wait to go on Send cal com mand and value to lY4 Go back and ca1 next higher range Wait 10 seconds for signal to Model 8573 Calibration Program Use the program below to calibration the Model 194 fro...

Page 186: ...tput to 3O OOVat a frequency of lkH2 5 Enable the zero mode on the Model 194 press ZERO 6 Change the calibrator frequency to 45kHz but leave the output at 3O OoV 7 Adjust C386 on the input amplifier F...

Page 187: ...MAINTENANCE Figure 7 5 Frequency Compensation Adjustment Locations 7 H...

Page 188: ...se parts will be received in anti static containers of plastic or foam Keep these devices in their original containers until ready for installation 2 Remove the devices from their protective container...

Page 189: ...EMBLY Removing the Top Cover The following paragraphs contain disassembly procedures 1 Remove the two screws that sccuw the top co er to the for the Models 194 and 1944 Generally disassembly rear pane...

Page 190: ...MAINTENANCE Figure 7 7 Top and Bottom Cover Removal 7 14...

Page 191: ...panel D Slide the module toward the front of the instrument slightly until the connectors clear the slot in the rear panel then remove the A D module completely E If necessary the input amplifier shi...

Page 192: ......

Page 193: ...ROVTE THROUGH BOTTOM 0411 OR TOP CHZI HOLE SOARD FRONT L RlSSON CASES FAN MODULE CONNECTlON ROUTE THROUGH BOTTOM CHlt OR TOP ICH21 HOLE AID MOTHER BOARD RIBBON CABLE GROUND CABLE Figure 7 9 Cable Conn...

Page 194: ...Remove the nut that holds the green ground wire to the rear panel and disconnect the wire 3 Remove the two nuts that secure the line receptacle filter and remove the receptacle 4 To remove the two BN...

Page 195: ...MAINTENANCE Figure 7 10 Case Disassembly _ 7 2117 22...

Page 196: ...MAINTENANCE Figure 7 11 Rear Panel Disassembly 7 23...

Page 197: ...MAINTENANCE Figure 7 12 Front Panel Disassembly 7 24...

Page 198: ...e instrument will check nun internal components including RAM and ROM nwm ri to make certain everything is in working order I uring the test procedure all front panel annunciators and disph segments w...

Page 199: ...mebase error B The A D memory pointer is examined to see if it wrapped around 7FFF hex If it did the jumper on the A D board is set for 32K otherwise it is set for 64K This information is stored for u...

Page 200: ...plies within the instrumwt should be checked first to make sure that all are functioning prw perly If the various operating voltages art not vithin the required limits troubleshooting the remaining ci...

Page 201: ...MAINTENANCE Figure 7 14 Troubleshooting Flow Chart 7 28...

Page 202: ......

Page 203: ...pin 2 12v 20 Referenced to VR104 pin 3 12 VRlO5 pin 3 5V 5 Referenced to VRlD4 pin 3 13 VR108 pin 1 25V 20 Referenced to VR108 pin 3 14 VR108 pin 2 15v 5 Referenced to VR108 pin 3 15 VR107 pin 2 25v 2...

Page 204: ...Stays low for 1OOmsecon power up then goes high 1OMHz square wave lMHz square wave High logic level Varying square wave approximately 1 4MHz 5MHz square wave Data bus pulses Data bus pulses Table 7 1...

Page 205: ...a Sawtooth waveform Display digit data Negative going pulses Keyboard scan data Pulses present when ZERO button is Returned key board data pressed Pulses present when TRIGGER button Returned keyboard...

Page 206: ...alue at various points in time For sampling rates of 1OOkHz and slower the AID converter samples with 16 bit resolution Above lOOkHz however the converter resolution is only eight bits Table 7 15summa...

Page 207: ...ge Apply 32O OOmV 488 321x O l 4 8832v 0 7 Apply 32O OOmV 488 321x O l 4 8832mV tO l Select 3 2V range Apply 3 2OOOV 4 8832 O l 4 8832V O l Apply 3 2OOOV 4 8832V O l 4 8832V O l Select 32v range Apply...

Page 208: ...gh Pin 11 low Sclcct 32V range Pins 4 and 13 low pin 12 high Pin 11 high Select 200V range Pins 4 and 12 high pin 13 low Pin 11 high High filter off low either filter on High filter off 50kHz filter l...

Page 209: ...A D trigger pulse every 10psec during measurement Select 3 2V range Apply 3 2767V Use DC calibrator 5 oov Sample hold input Select 3 2768V output full range input 5 oov Sample hold input Adjust for 3...

Page 210: ...when range button is pressed Pulse burst when range button is pressed Program 10 000 samples A D data at sampling rate Odd bit data Even bit data Data shift cnablc Data shift clock AID trigger pulse S...

Page 211: ...of the I O circuit board as follows I 1 Remove the I O board from the instrument as covered in paragraph 7 7 2 Install the correct pull up resistor at location R409 5V or R410 UV Figure 7 17shows the...

Page 212: ...MAINTENANCE 4 m CZD 0 X i Figure 7 16 Fan Filter Removal Figure 7 17 2 Output Blanking Level Programming FAN GUARD...

Page 213: ...MAINTENANCE Figure 7 18 Movable Jumper Locations 7 40...

Page 214: ...ion concerning replacement parts contact your Keithley representative or the factory When ordering parts include the following information 1 Instrument model number 2 Instrument serial number 3 Part d...

Page 215: ...REPLACEABLE PARTS x p b i I 0 Yx A 0 0 m q am Figure 8 1 Mechanical Parts Locations Cl 318 4...

Page 216: ...tic Capacitor 2200pF 16V Aluminum Electrolytic Capacitor lOOOpF 35V Aluminum Electrolytic Capacitor lOOOhF 35V Aluminum Electrolytic Capacitor l 5OV Ceramic Film Capacitor O l 5OV Ceramic Film Capacit...

Page 217: ...ilicon lN4148 Diode Silicon lN4148 Fuse A 25OV 3AG SLO BLO 230V operation Fuse lA 25OV 3AG SLC BLO 115V operation Fuse 6A 8AG Line Filter Connector BNC Connector BNC Connector IEEE 488 Connector Pin C...

Page 218: ...l 5 aW Composition Resistor lkn 5 XW Composition Resistor lOk0 5 aW Composition Resistor 470k0 5 aW Composition Resistor 23 2kn l W Resistor 3 3k0 5 XW Composition Resistor 3 3kD 5 aW Composition Resi...

Page 219: ...nsceiver 75161A IC Triple 3 Input AND Gate 74LSll IC General Purpose Interface Adapter 99 14 IC D Type Flip flop 74LS74 Regulator IC 15V 78M15 Regulator IC 15V 7915 Regulator IC 15V 7915 Regulator IC...

Page 220: ...REPLACEABLE PARTS Figure 8 2 Mother Board Component Location Drawing Dwg No 194 100 S 10...

Page 221: ...1...

Page 222: ...I N I 0 I...

Page 223: ...I N I 0 I i i i...

Page 224: ...6 86 B6 Ch Cl5 B6 C6 1 6 B6 C6 Ch Bh C6 Ch C6 B6 B6 1 6 C6 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 SW 435 S...

Page 225: ...on Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton Switch Pushbutton...

Page 226: ...REPLACEABLE PARTS Figure 8 4 Display Board Component Location Drawing Dwg No 194 110 8 20...

Page 227: ......

Page 228: ...0 1 c319 Capacitor O F 5OV Ceramic Film 4lD6 C 237 0 1 C320 Capacitor 0 1 F 5OV Ceramic Film 4iC6 C 237 0 1 C321 Capacitor O F 5OV Ceramic Film 4iC6 c 237 0 1 C323 Capacitor O l 20 50V 3iE6 C 365 0 1...

Page 229: ...inum Electrolytic Capacitor O I 5OV Ceramic Film Cauacitor 4 40pF Trimmer Cabacito 18pF Capacitor O lpF 5OV Ceramic Film Capacitor 0 1 F 5OV Ceramic Film Caoacitor 18pF C it IObOpF Capacitor 18pF Caoa...

Page 230: ...Transistor N Channel JFET Selected 2N4392 2iA3 TG 77 Q307 Transistor N Channel JFET Selected 2N4392 2181 TG 77 no40 Connector CS 236 1 1042 Connector CS 236 R301 Resistor 1004 5 XW Composition 3iFl R...

Page 231: ...tal D Type Flip Flop 74LS374 IC S Bit Shift Register 74LSl64 IC Versatile Interface Adapter 6522 IC Quad 2 Input OR Gate 74LS32 IC Quad 2 Input OR Gate 74LS32 IC Dual D Type Flip Flop 74LS74 IC Quad 2...

Page 232: ...4 1 A4 IC 251 U362 IC D Bit Digital Analog Converter DACROCVl N l B3 IC 323 u363 IC l2 Bit Digital Analog Converter DACBOCVl N l B1 IC 323 U364 IC 4 Digit CMOS Display Decoder Driver HP 2630 2lA6 IC 3...

Page 233: ...ont Schematic Designation W301 W302 w303 w304 Y301 Description Connector Pin Connector Pin Connector Pin Connector Pin Crystal Oscillator Circuit 10MHz Schematic Location 41N5 4iN5 liD4 Keithley Part...

Page 234: ...REPLACEABLE PARTS Figure 6 6 AID Board Component Location Drawing Dwg No 194 120 8 30...

Page 235: ......

Page 236: ...I N I 0 I ID...

Page 237: ...N...

Page 238: ...L 1L I 4 0 m a...

Page 239: ...con lN4148 Diode Silicon lN4148 Diode Silicon lN4148 Connector BNC Connector BNC Connector BNC Connector 26 Pin Connector 20 Pin Choke Ferrite Choke Ferrite Choke Ferrite Transistor Silicon NPN 2N3904...

Page 240: ...95A IC Peripheral Interface Adapter 65C21 IC Darlington Array UNL2003A IC Darlington Array UNL2003A IC Versatile Interface Adapter 6522A IC 1 of 8 Decoder 74LSl 38 IC 8 Bit Register 74LS273 IC 8 Bit R...

Page 241: ...REPLACEABLE PARTS Figure 8 8 I O Board Component Location Drawing Dwg No 194 160 8 42...

Page 242: ...I N I I 7 I D...

Page 243: ...Capacitor O F 20 5OV Ceramic Film C 237 0 1 NO44 Connector e 445 5 MO45 Connector CS 445 h U601 IC 8 Bit Shift Register 74LS164 IC 127 U602 IC B Bit Shift Register 74LS164 IC 127 IJ603 IC B Bit Shift...

Page 244: ...REPLACEABLE PARTS J I Figure 8 11 Sample Rate Board Schematic Diagram Dwg No 194 176 8 46...

Page 245: ...er Pushbutton Power Rear Panel Fan Set Fan Guard Fan Filter Fan Filter Spacers Line Filter Mounting Rails Top Cover Bottom Cover Rear Foot Front Foot Assemblv Decorative Strip Asknbly Decorative Strip...

Page 246: ...se Holder Digital Fuse 1 Fuse Holder Line Fuse 1 Fuse Carrier Line Fuse 1 Shield Input Amplifier 1 Cover Plate 4 Standoff Mounting 1 Line Cord 6 Heat Sink 2 Programming Card Slide Bracket 1 Shield A D...

Page 247: ...STX GTL 3 03 ETX 4 04 EOT SDC 5 05 ENQ PPC 6 06 ACK 7 07 BEL 8 08 BS GET 9 09 HT TCT 10 OA LF 11 OB VT 12 oc FF 13 OD 14 OE 15 OF SI 16 10 DLE 17 11 DC1 18 12 DC2 19 13 DC3 20 14 DC4 21 15 NAK 22 16 S...

Page 248: ...32 2 51 33 3 52 34 4 53 35 5 54 36 6 MLA 0 MLA 1 MLA 2 MLA 3 MLA 4 MLA 5 MLA 6 MLA 7 MLA 8 MLA 9 MLA 10 MLA 11 MLA 12 MLA 13 MLA 14 MLA 15 MLA 16 MLA 17 55 37 7 MLA 18 MLA 19 MLA 20 MLA 21 MLA 22 MLA...

Page 249: ...4E 79 4F C D G H r K L M N 0 80 50 P 81 51 82 52 83 53 S MTA 0 MTA 1 MTA 2 MTA 3 MTA 4 MTA 5 MTA 6 MTA 7 MTA 8 MTA 9 MTA 10 MTA 11 MTA 12 MTA 13 MTA 14 MTA 15 MTA 16 MTA 17 MTA 18 MTA 19 MTA 20 MTA 2...

Page 250: ...A 10 PPE MSA ll PPE 108 6C 1 MSA 12 tiPE 709 6D m MSA l3 PPE 110 6E MSA 14 PPE 111 6F 0 MSA 15 PPE 112 70 P MSA 16 PPD 113 7l q MSA 17 PPD 114 72 r MSA lB PPD 115 73 s MSA l9 PPD 116 74 t MSA 20 PPD 1...

Page 251: ...APPENDIX B Setup Configuration Worksheets The following worksheets will allow you to record instrument operating modes fol the various setup values s 1...

Page 252: ...APPENDIX FJ Setup Configuration Worksheets Worksheet 1 t q IEEE 488 Primary Address B 2...

Page 253: ...torange on off ZWO Zero Value Filter Singleicont Trigger Arming Trigger Source Trigger Delay samples or period Trigger Slope Trigger Level Setup 1 setup Sampling Rate interval or frequency Number of S...

Page 254: ...APPENDIX B Setup Configuration Worksheets Worksheet 3 B 4...

Page 255: ...e included l IBM PC or XT with Keithley Model 8573 IEEE 488 Interface l Apple II equipped with the Apple II IEEE 488 Interface Hewlett Packard Model 85 l Hewlett Packard Model 9816 l Hewlett Packard M...

Page 256: ...OAD DECL and press the return key 5 Add the lines below to lines l 6 which are now in memory Modify the address in lines 1 and 2 as described in the Model 8573 Instruction Manual 6 Run the program and...

Page 257: ...pe in the desired command string at the command prompt For exam ple to place the instrument in the autorange and average modes type in ROFlX and press the return key 5 The instrument reading string wi...

Page 258: ...HP 85 computer 3 Enter the lines in the program below using the END LINE key after each line 4 Press the HP 85 RUN key and type in the desired command string at the command prompt For example to place...

Page 259: ...in the 9816 computer 3 Type EDIT and press the EXEC key 4 Enter the lines in the program below using the ENTER key after each line 5 Press the 9816 RUN key and type in the desired command string at t...

Page 260: ...omatically assigned by the 9825A 4 Press the 9825A RUN key and type in the desired command string at the command prompt For example to place the instrument in the autorange and average modes type in R...

Page 261: ...pile using the FORTRAN compiler as follows FORTRAN IEEE 5 Link with the system and IB libraries as follows LINK IEEE IBLIB 6 Type RUN IEEE and press the RETURN key 7 The display will read ENTER ADDRES...

Page 262: ...nd prompt For example to place the instrument in the autorange and average modes type in ROFlX and press the RETURN key 5 The instrument reading string will then appear on the CRT A typical display is...

Page 263: ...TER CANCEL FREQiTlME Data Entry O 9 I MHz kHz Hz CHl CH2 CHl CHZ OTHER WAVEFORM PK TO PK STD DEV INTEGRAL SETUP i Equivalent IEEE 488 Command s 24 5 I T 00 oo T 02 r I N S CTLt C 1x1 RI R4 Rl R4 None...

Page 264: ...clE6Hz m number of samples 1 srn 65 535 R bit l m132 767 16 bit m measurement duration in set 0 5 m 5 65 534F3 8 bit 0 5 m 5 32 766 16 bit Continuous talk Single talk Continuous GET Single GET Continu...

Page 265: ...easurement Buffer 03 l 64k RAM Buffer 03 2 Display Readings 03 3 IEEE 488 Reading Buffer 04 m m X Output Full Scale Voltage 1 sm 5 10 05 m m Y Output Full Scale Voltage 1 sm 510 06 m m Z Output Blanki...

Page 266: ...ranslator list SRQ disabled Overflow Data condition Button pressed Reading done Ready Error Channel 1 A D module Channel 2 A D module Composite channel 1 2 disF EOI and hold off on X enabled EOI disab...

Page 267: ...Engineering Units and Scientific Notation Conversion Engineering Symbol femto pico nano micro milli kilo mega giga tera peta Prefix f P F m k M G T P Scientific Notation 10 lo 10 q 10 e lo 10 10 lo 1...

Page 268: ...er and listener The controller does what its name implies it controls other devices on the bus A talker sends data usually to the cotl troller and a listener receives data Depending on the in strument...

Page 269: ...ses eight data lines to transmit and receive data in bit parallel byte serial fashion These lines use the con vention DIOl Dl08 instead of the more common DO D7 DlOl is the least significant bit while...

Page 270: ...e Table G l IEEE 488 Bus Command Summary Command Type Uniline Multiline Universal Addressed Unaddressed Device dependenl Command Command REN Remote Enable REN Remote Enable EOI EOI IFC Interface Clear...

Page 271: ...hich is used to determine which device on the bus is requesting service SPD Serial Poll Disable SPD is used by the controller to remove all devices on the bus from the serial poll mode and is generall...

Page 272: ...f device dependent commands will depend on instrument configuration Generally these commands are sent as one or more ASCII characters that command the device to perform a specific action For example t...

Page 273: ...APPENDIX G Figure G 3 Command Codes G 6...

Page 274: ...Addressed Command Sequence Command ATN State UNL 1Set low Table G 4 gives a typical device dependent command se quence In this instance ATN is true while the instrument is being addressed but it is s...

Page 275: ...e A high level programming language used in many small computers Binary A number system based on the number 2 used extensively in computer based equipment Bit An abbreviation for binary digit A unit o...

Page 276: ...driven into the ground H 2 EMI Abbreviation for Electromagnetic Interference A term that defines unwanted electromagnetic radiation from a device which could interfere with desired signals in electron...

Page 277: ...when re questing data from the instrument The start pointer defines the first location to be accessed and the end pointer dictates the last location to be accessed Programmable Instrument An instrume...

Page 278: ...which allows English like words to be used in place of instrument bus commands Trigger An external stimulus of home sort that initiates one T more measurement or scan sequences TRMS Reading The True...

Page 279: ...REN Remote Enable 4 11 SDC Selectve Device Clear 4 14 SPE SPD Serial Polling 4 15 Bus Connections 4 3 Bus Data Transmission Times 4 54 Cable Connections 7 19 Calibration Connections 7 X Circuit Board...

Page 280: ...nction Codes 4 6 Jumper Locations 7 40 Line Fuse Selection 7 2 Line Voltage Selection 7 1 7 4 Loading Effects 3 44 Local Lackout LO 4 12 Mathematical Functions 3 29 3 33 Measurement Considerations 3 4...

Page 281: ...ed whether power is turned on or not Also describe signal source Where is the measurement being performed factory controlled laboratory out of doors etc What power line voltage is used Variation Frequ...

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