Keithley 707A Instruction Manual Download

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Summary of Contents for 707A

Page 1: ...Model 707A Switching Matrix Instruction Manual Contains Operating and Servicing Information KEITH LEY 707A 901 01 Rev A 9 98...

Page 2: ...E REMEDIES PROVIDED HEREIN ARE BUYER S SOLE AND EXCLUSIVE REMEDIES NEITHER KEITHLEY INSTRUMENTS INC NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT INDI RECT SPECIAL INCIDENTAL OR CONSEQUENTIA...

Page 4: ...rate immediately into the manual Addenda are num bered sequentially When a new Revision is created all Addenda associated with the previous Revision of the manual are incorporated into the new Revisio...

Page 5: ...y unknown circuit before measuring Users of this product must be protected from electric shock at all times The responsible body must ensure that users are prevented access and or insulated from every...

Page 6: ...humans Before performing any maintenance disconnect the line cord and all test cables To maintain protection from electric shock and fire replacement components in mains circuits including the power...

Page 7: ...EEE 488 GET lms RESPONSE TO IEEE 488 COMMAND to close a single relay excluding relay settling time Stand Alone 15ms Master and Four Slaves 55ms DOWNLOAD TIME one setup to 707A Stand Alone 60ms typical...

Page 8: ...tallation 2 1 Installing and removing cards 2 1 3 Getting Started 3 1 Introduction 3 1 3 2 Front panel familiarization 3 1 3 3 Rear panel familiarization 3 6 3 4 Card connections 3 8 3 5 Expanding mat...

Page 9: ...oint display 4 10 4 7 Copying crosspoint display 4 1 4 8 Inserting and deleting stored setups 4 12 4 9 Menu operations 4 12 4 9 1 Digital I O 4 14 4 9 2 External trigger 4 14 4 9 3 Matrix ready 4 15 4...

Page 10: ...lockout GTL go to local DCL device clear SDC selective device clear GET group executive trigger SPE SPD serial polling Device dependent command DDC programming Overview A External trigger B Matrix rea...

Page 11: ...ital I O 6 17 6 9 IEEE 488 bus interface 6 17 6 10 Power supply 6 19 7 Maintenance 7 1 Introduction 7 1 7 2 Line voltage sensing 7 1 7 3 Fuse replacement 7 2 7 4 Fixed rack installation 7 2 7 5 Disass...

Page 12: ...nagement lines B 3 B 3 3 Handshake lines B 3 B 4 Bus commands B 4 B 4 1 Uniline commands B 4 B 4 2 Universal multiline commands B 5 B 4 3 Addressed multiline commands B 5 B 4 4 Address commands B 5 B...

Page 13: ...ter slave column locations Example of master slave row expansion 3 2 3 3 3 7 3 8 3 9 3 10 3 11 3 12 3 13 3 14 3 15 3 16 3 17 3 18 3 19 4 Operation Figure 4 1 Paths for relay setup data 4 1 Figure 4 2...

Page 14: ...digital input 5 38 Figure 5 23 U8 relay test input 5 38 6 Principles of Operation Figure 6 1 Model 707A block diagram 6 2 Figure 6 2 Digital board block diagram 6 3 Figure 6 3 RAM and battery backup...

Page 15: ...B IEEE 488 Bus Overview Figure B 1 IEEE 488 bus configuration B 2 Figure B 2 IEEE 488 handshake sequence B 3 Figure B 3 Command codes B 6 IX...

Page 16: ...4 8 Front pane messages for trigger sources 4 20 5 IEEE 488 Programming Table 5 1 Sample strings 5 2 Table 5 2 Contact assignments 5 5 Table 5 3 Model 707A interface function codes 5 6 Table 5 4 Basi...

Page 17: ...slave checks 7 13 Table 7 11 Display board checks 7 14 8 Replaceable Parts Table 8 1 Digital board assembly 8 2 Table 8 2 Display board assembly 8 3 Table 8 3 Backplane assembly 8 3 Table 8 4 Voltage...

Page 18: ...D display shows the current relay status a stored setup or an editing scratchpad High speed triggering of stored setups Make break and break make switching are programma ble by rows Operation is trans...

Page 19: ...on or the equivalent and include the following information Call the repair department at 1 800 552 1 1 15 for a Repair Authorization RMA number Advise as to the warranty status of the mainframe Write...

Page 20: ...l 707A front panel It is used to toggle the states of crosspoint LEDs make break LEDs and break make LEDs A pen holder is included Model 7079 Slide Rack Mounting Kit The Model 7079 kit consists of two...

Page 21: ...slot cover from the desired slot 3 With one hand grasping the card s handle and the other supporting its weight line up the card with the card guides in the slot Ensure that the component side is fac...

Page 22: ...oor the Model 7079 slide rack kit is rec ommended for rack mounted units 5 To remove a matrix card first turn off the mainframe and disconnect the line cord Ensure no voltage is applied from the user...

Page 23: ...ws and columns 3 5 Expanding Matrix Size Discusses methods for expanding the matrix both internal to the mainframe and with multiple units 3 6 Basic Switching Operation Provides a general proce dure f...

Page 24: ...II I I III I H lllll l ggsiBagB MitfaraWaWM YYYYYYYY OM kOZ X 3 8 H AA1 JIA AWtfftViTflfl IMMWiSH 1 1 1 t 1 rrrrrr kAAMttSBwH f o rt a C Ow OX 1 1 1 1 i 1 i 1 p cp rrrrrm y rYTTTTT TTTTTTTT y y y y y...

Page 25: ......

Page 26: ...es higher stored setups up one memory location DELETE Deletes the setup at the location shown in the MEMORY STEP field Moves higher stored setups down one memory location MENU Steps through the availa...

Page 27: ...and exits menu mode except when digital I O is displayed RESET Performs the same functions as cycling power all relays are opened triggers are disabled RELAY STEP to 000 MEMORY STEP to 00 1 etc excep...

Page 28: ...selected by a menu item It goes false when relays are switched and goes true after the sum of the relay setting time and the programmed settling time RELAY TEST A 6 pin quick disconnect terminal bloc...

Page 29: ...Figure 3 3 Model 707A rear panel 3 7...

Page 30: ...d for multiple applications Using the Model 7072 as an example the recommended connections are as follows Rows A and B low current Picoammeters electrometers Rows C through F general purpose DMMs sour...

Page 31: ...1 Row column and column column paths Possible paths for Possible paths for Connection scheme Crosspoints per path 8 rows by 12 columns 8 rows by 72 columns Row column 1 96 576 Column column 2 66 2556...

Page 32: ...edge connectors as shown in Figure 3 6 and described below Upper connectors J101 J106 Consists of two ana log buses pins 1 22 and pins 23 86 to expand card rows Middle connectors J107 JT12 34 pin con...

Page 33: ......

Page 34: ...I HI HI HI Row LO LO LO LO Guard Guard Guard Guard Guard J101 Guard J102 Guard J103 J105 J106 Guard HI HI HI HI Row LO LO LO LO Guard Guard Guard Guard Guard Guard Guard Guard HI HI Hi HI Row LO LO LO...

Page 35: ...l to the mainframe When a mainframe contains different card models instru ments must be connected to each card type because of the differing analog bus usage An example of this is shown in Figure 3 10...

Page 36: ...External expansion within a single mainframe is possible with user installed wiring between rows and columns of like cards The available accessory cables for external connec tions are listed in Table...

Page 37: ...2 7072 HV 7172 7174 7078 TRX lO 3 lug Triax Triax Cable 10 ft rows columns 7051 2 BNC BNC Cable 2 ft 7073 7173 50 rows columns 7051 5 BNC BNC Cable 5 ft 7074 KIT Mass Terminated Cable Kit 7074 banks 7...

Page 38: ...ne by connecting the rows of like cards in separate units as shown previously in Figure 3 12 but also by connecting the units in a closed loop of DIN cables for communication and control A master slav...

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Page 41: ...ernal Internal External Internal Row Row Row Row Connections Connections Connections Connections Slaves 1 and 2 8 Rows by 144 Columns Columns Columns Columns Columns 217 228 227 228 289 300 349 360 Ex...

Page 42: ...7072 and 7073 When card types are mixed in a system the longest settling time is in effect Bus communication A master slave setup responds slower to bus commands because all communication is through t...

Page 43: ...Getting Started Table 3 5 Model 707A card configuration 3 21...

Page 44: ...rrent relay setup RELAY STEP to 000 a pseudo setup memory that is cleared at powerup and sent to the relays MEMORY STEP to 001 Other powerup defaults are detailed in paragraph 4 3 3 6 2 Selecting make...

Page 45: ...ation Step 2A Sending setup to relays To make the newly modified setup the current relay setup just press the COPY DISPLAY RELAYS key The relay states will be changed to reflect the modified setup dat...

Page 46: ...operation including digital I O external trigger matrix ready master slave IEEE 488 bus address relay settling time card identification self test and factory defaults 4 10 Selecting Switching Paramete...

Page 47: ...the ac receptacle on the rear pane of the instrument The other end of the cord should be connected to a grounded ac outlet WARNING The Model 707A must be connected to a grounded outlet to maintain con...

Page 48: ...the programmed primary IEEE 488 address as in this example AOl IEEE 18 Knowing the software revision level is useful when dis cussing problems with Keithley Instruments In this ex ample the factory d...

Page 49: ...unit the master and the other units slaves and exits menu mode During subsequent power ups of master slave configura tions all connected mainframes wait for all units to get power before initializing...

Page 50: ...oint LEDs lit Send only valid commands see Section 5 IDDC Invalid device dependent command IDDCO Invalid device dependent command option Send only valid command options see Section 5 INVALID INPUT Inv...

Page 51: ...triggering NOT SETTLED Additional trigger received before programmed settling time expired trigger is processed 4 4 3 IEEE 488 status indicators The TALK LISTEN and REMOTE LEDs shown in Figure 4 2 ind...

Page 52: ...aTaTitfgga WWtftfSWi I I I I I I I rTTTTTT rrrrrrr p p p tp p rp tp n j Cp p p p p j p tp Cp tp tp p P cjr YY fTrTrTTi fTrrrrr p tp p p rrrrrm p p p p p p p p p p p p p fTTTTTT I I I 1 I I I I O AOQM...

Page 53: ...ut device for toggling the on off states of crosspoint display LEDs MAKE BREAK row LEDs and BREAK MAKE row LEDs One light pen is used to control the LEDs of all units in a raaster slave system As seen...

Page 54: ...Saew Hold Figure 4 4 Light pen...

Page 55: ...ld When location 000 is selected in this manner the relay states do not change When the RELAYS indicator is lit a setup can also be sent to the relays and displayed by entering a valid location and pr...

Page 56: ...mber of simultaneously closed cross points depends on the specified drive current per crosspoint of each card The total relay drive current required per main frame cannot exceed 48 5A since the 6V 50A...

Page 57: ...EP field is set there and then the deletion takes place In master slave configurations the insert blank setup and delete stored setup operations perform similarly except on all units of the system Fig...

Page 58: ...MATRIX RDY HI Select matrix ready output level active LO or HI multiple choice STANDALONE MASTER Select stand alone or master slave operation multiple choice IEEE 488 nn Program IEEE 488 bus address n...

Page 59: ...to exit menu mode or press MENU to continue to the next item Each time the digital outputs are programmed even if the states are not changed the control line OUT PULSE is brought low Figure 4 8 Digit...

Page 60: ...me Programmed Settling Time B Rising edge of pulse A Matrix ready high true Figure 4 10 Sample external trigger pulses To choose the alternate external trigger state use the SCROLL A or keys then pres...

Page 61: ...e units are powered up one at a time they will display the message M S LOOP DOWN until all units are powered CAUTION When it is necessary to cycle power on a slave unit turn off all units in the maste...

Page 62: ...ccuracy not guaranteed 3 Outputs set to all low 4 9 5 IEEE 488 bus address The Model 707A communicates over the IEEE 488 bus through the rear panel connection shown in Figure 4 13 When connected to a...

Page 63: ...Continue pressing the SCROLL A or y keys for the remaining slots or press CANCEL to exit the menu mode In master slave configurations all units display card labels simultaneously 4 9 8 Self test The s...

Page 64: ...sconnect the present circuit before connecting a new circuit It is used to avoid momentary shorting of two voltage sources Both of these switching operators are sup ported by the Model 707A Rows of cr...

Page 65: ...sources The programmed trigger source provides the stimulus to increment to the next stored setup Trigger sources include Front panel MANUAL key When triggers are enabled this key is always operationa...

Page 66: ...timing is for setups with no make break or break make rows When either make break or break make operation is selected but not both the Model 707A switches through an intermediate setup to ensure prope...

Page 67: ...Close Don t Care Commands NA2 CAS Setup Data Shift H Ready Relay Settling Time Programmed Settling Time Matrix Ready TRIG OVERRUN NOT SETTLED Message Additional Trigger not Processed Additional Trigg...

Page 68: ...N Intermediate Setup 12 3 12 3 k k A g k k k k 7 Break Break Operation Setup N 1 o o Commands f NA 2 B2 k t CAS B3 c k Open Break Make Close Break Make Open Don t Care Close Don t Care Setup Data Shif...

Page 69: ...eak Make Open Don t Care Close Don t Care Commands NA2 B2 C2 CA3 B3 C3 Setup Data h Shift Setup Data Setup Data h Shift Setup Data r Shift Belay Belay Belay jiip mn Belay Settling Time Settling Time S...

Page 70: ...dge of the true level indicates the end of the total settling time relay settling time plus programmed settling time 4 1 1 6 IEEE 488 bus triggering To trigger a setup change with an IEEE 488 trigger...

Page 71: ...idually Consequently the pri mary address of your Model 707A must be the same as the primary address specified in the controller s programming language or you cannot program the instrument Each device...

Page 72: ...pen and close crosspoints You can open close and clear crosspoints by sending the appropriate command which is made up of an ASCII letter representing the command followed by one or more charac ters f...

Page 73: ...ANY KEY TO CONTINUE DO LOOP WHILE INKEY PRINT 1 OUTPUT 18 F1T2X PRINT 1 IR iaSER 18 Wait for keypress Enable triggers select trigger on GET Trigger setup 1 to relays When any key on the keyboard is pr...

Page 74: ...er connecting method I Line up the connector on the cable with the connector on the rear panel of the instrument Figure 5 4 shows the IEEE 488 connector location O o r 1 MASTEK EXTSWtAI tLAVC THOOCR i...

Page 75: ...6 Talker The ability of the Model 707A to send data over the bus to other devices is defined by the T6 function Model 707A talker capabilities exist only after the instru ment has been addressed to ta...

Page 76: ...ess The primary address may be set to any value between 0 and 30 as long as address conflicts with other instruments are avoided Note that controllers are also given a primary address so do not use th...

Page 77: ...he whole program is used to avoid redundancy At the beginning of each program driver files must be opened The input ter minator should be set for CRLF For example OPEN ieee FOR OUTPUT AS 1 OPEN ieee F...

Page 78: ...eady bit is set Card identification error A card ID error occurs when the instrument s power up rou tine detects a checksum error in the information from a card When in master slave configuration the...

Page 79: ...trument is triggered while it is still processing a setup change from a previous trigger and before the READY for trigger signal is asserted READY is a bit in the SPOLL byte See paragraph 5 8 for a co...

Page 80: ...essary to press LOCAL after pro gramming over the bus Note that LOCAL is also inop erative if the LLO Local Lockout command is in effect 2 Front panel parameter modification should always be completed...

Page 81: ...t set REN false 5 8 6 DCL device clear The DCL command may be used to clear the Model 707 and return it to its power up default conditions see Table 5 2 Note that the DCL command is not an addressed c...

Page 82: ...evice dependent command DDC programming 5 9 1 Overview IEEE 488 device dependent commands control most instru ment operating modes All front panel modes such as trigger source and settling time as wel...

Page 83: ...7A is summarized in Table 5 10 Note that the X com mand is listed first since it is the character that forces the exe cution of the rest of the commands If you wish to force a particular order of exec...

Page 84: ...1 41 5 9 9 Insert Blank Setup In Insert blank setup in memory I 100 5 9 10 Self test JO Perform self test 5 9 11 EOI and Hold off KO Send EOI hold olf on X until Ready 5 9 12 K1 No EOI hold off on X...

Page 85: ...Send digital input of unit 0 65535 U8 Send RELAY TEST input Make Break Vabcdefgh Select rows for make break operation abcdefgh 0 X 00000 5 9 23 to 11 111 111 Break Make Wabcdefgh Select rows for break...

Page 86: ...al increments the RELAY STEP pointer and copies the setup indicated by the new value from memory to the relays Figure 5 8 shows example trigger pulses Trigger on external must be the selected source T...

Page 87: ...ling time and user programmed settling time Figure 5 9 shows exam ple Matrix Ready signals 1 The Matrix Ready signal is negated by anything that causes a change to a relay state even if no relays actu...

Page 88: ...Close one crosspoint PRINT 1 OUTPUT 18 CA55 A5 6 B4 9 B5 OX Close multiple crosspoints 5 9 5 D Display Purpose To write messages on the front panel alphanumeric display of a stand alone or master uni...

Page 89: ...earing stored crosspoints directly and not just turning on off crosspoint LEDs Example PRINT 1 OUTPUT 18 E0X Point to relays PRINT 1 OUTPUT 18 E50X Point to Stored relay setup 50 5 9 7 F Enable disabl...

Page 90: ...ts in a setup are sent in printable ASCII An ASCII represents an open crosspoint and an ASCII X repre sents a closed crosspoint For GO all data is sent in one talk for Gl the data from one row of one...

Page 91: ...osed crosspoints Master Slave 1 Slave 2 Slave 3 Slave 4 A1 A2 B3 B5 C7 C8 D9 D10 Fll F12 A13 A14 C15 C16 E17 E18 A25 A26 H27 H30 A36 A37 H38 H43 G48 G49 A50 A51 H55 H56 E57 E60 Obtaining data Generall...

Page 92: ...Note 1 9 641 79 Note 1 45 3205 G2 Note 2 1 Note 2 Note 2 I Note 2 G3 Note 2 1 Note 2 Note 2 1 Note 2 G4 154 1 154 770 1 770 G5 154 1 154 154 5 Note 3 770 G6 76 1 76 380 1 380 G7 76 1 76 76 5 Note 3 38...

Page 93: ...00000 SETUP NUMBER 2 BYTES UNIT NUMBER 1 BYTE CARD 1 COLS 1 12 CARD 6 COLS 61 72 CHECKSUM SLAVE 1 0003 01 010100000000 040400000000 000000000000 000000000000 101000000000 000000000000 XX 000000000000...

Page 94: ...00000 00000000 00000000 00000000 00000000 00000100 00000100 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000...

Page 95: ...H27 4 H7 SCROLL T H28 1 H8 INSERT H29 0 H9 DELETE H30 8 mo MENU H31 5 mi SETTLING TIME H32 2 H12 MAKE BREAK H33 CANCEL H13 BREAK MAKE H34 9 H14 LOCAL H35 6 H15 ENABLE H36 3 H16 SOURCE H37 ENTER H17 MA...

Page 96: ...paragraph 5 9 22 Any front panel keypress or bus command overrides the message Programming notes 1 The value n if sent must be zero 2 Allow approximately four seconds for the instrument to complete t...

Page 97: ...until Ready PRIOT 1 OUTPUT 18 K2X Send EOI with last byte do not hold off on X 5 9 13 L Download setups Purpose To download setups from the controller to the Model 707 A Format Lbbbb X Parameters bbbb...

Page 98: ...hecked to determine if the Model 707A was the instrument that generated the SRQ and if so what conditions caused it The general format of the SRQ mask used to generate SRQs is shown in Figure 5 14 By...

Page 99: ...the SRQ line cleared by a serial poll 1 The serial poll byte should be read once the instrument has generated an SRQ to clear the SRQ line 2 All bits in the serial poll byte latch when the instrument...

Page 100: ...ter with four slave units An IDDCO results if the maximum value is exceeded 4 This command is equivalent to multiple light pen operation s Example priot 1 output 18 NA55X Open one crosspoint PRINT 1 O...

Page 101: ...cleared This command is equivalent to multiple front panel key presses PRIisrr 1 OUTPUT 18 POX open all relays PRINT 1 OUTPUT 18 P20X Clear relay setup 20 5 9 18 Q Delete setup Purpose Format Paramete...

Page 102: ...s Set full output format all data sent in one talk Send EOI with last byte hold off on X until ready Disable all SRQ sources Set all digital outputs to logic low Set user settling time to zero Trigger...

Page 103: ...on power up or after receiving a DCL SDC or ROX command the instrument defaults to T7 Trigger on External Trigger pulse With the trigger command you can determine the trigger source over the bus or fr...

Page 104: ...triggers program trigger on GET PRINT 1 OUTPUT 18 FIX Enable triggers PRINT 1 t riTD 1 O 1 _Lo Trigger next setup 5 9 22 U Status Purpose To obtain instrument status and system configuration Format Un...

Page 105: ...707A error conditions The error status word Figure 5 17 is a string of ASCII characters representing binary bit positions Reading the U1 status clears the error bits An error condition is flagged in t...

Page 106: ...ng error in the master slave loop Power up Initialization Failed The power up routine has detected a checksum error in the information from one or more cards Setup Checksum Error The power up routine...

Page 107: ...own in Figure 5 20 The character string for an empty slot is NONE Identifier CiDO l mmmmm 2 mmmmmm3 minmmmm 4 mmmmmm 5 mmmmmm 6 mmmfnmm TERM EOI Model Number Card Slot Unit Number 0 4 Figure 5 20 U5 c...

Page 108: ...e corresponding U command is received 2 To ensure that correct status is indicated the status word should be requested immediately after the command is transmitted The status sent by the Model 707A is...

Page 109: ...eak operation to keep current flowing and elim inate switching transients When switching voltage sources use break make operation to avoid momentary shorting of two paths together 4 Given the present...

Page 110: ...device dependent commands received since the last X Format com mand X Description Programming notes Example The execute command is implemented by sending an ASCII X over the bus Its purpose is to dir...

Page 111: ...The programmed terminator is sent at the end of the transmission each time the Model 707A is addressed to talk regardless of the selected data format 3 Status word programming is covered in paragraph...

Page 112: ...command string EOPOCAIX sets the edit pointer to the present relay setup opens all relays and closes crosspoint Al A1 will be the only closed crosspoint Example 2 The string E0Z5 0CA1X sets the edit p...

Page 113: ...econd Assuming the transfer speed of the controller does not affect the listening rate of the Model 707A For example the CA1 CA5X command string will take 2ms to transmit from the controller to the Mo...

Page 114: ...OX 3 3ms EOI and Hold olF KOX 4 4ms Download Setup Lbbb X 56 0ms Binary format G6 G7 SRQ M32X 4 9ras Open Crosspoint s Similar to Close Crosspoints C times Digital Output 0255X 5 8rns Clear Crosspoint...

Page 115: ...ownload Setup Lbbb X 68 5ms Binary format G6 G7 SRQ M32X 12 0ms Open Crosspoint s Similar to Close Crosspoints C times Digital Output 0255X 12 9ms Clear Crosspoints POX 47 8ms P55X 48 8ras Delete Setu...

Page 116: ...Address decoding PALs U 1 U2 32Kx8 bit EPROM U7 32Kx8 bit RAM U8 with battery back up BTl U3 The microcomputer centers around the 8 bit 68B09 micro processor The MPU has direct control over relay swit...

Page 117: ...appears as 12K bytes of address space to the microprocessor Ul also decodes the three bank select lines BS3 BS0 from the PB6 PB4 outputs of U9 a 6522A versatile interface adapter VIA The RAM is decode...

Page 118: ...2 Digital hoard block diagram 32Kx8 EPROM ITE 3SKx8 Battery RAM Backup ZJE System tick Timer 6 Card Select RELAYDATA CLK STROBE CLRAOOR NEXTADDR iODATA Matrix Card Interface fEEE 488 Tri er EXTERNAL...

Page 119: ...battery BTl It also disables chip enable CE to the RAM when Vcc is outside the specified limits See the paragraph describing the reset circuitry In addition if the battery power goes below a specified...

Page 120: ......

Page 121: ...e SELECT RELAYDATA decode line goes high causing the output of the U5 74HCT08 AND gate to go high This signal ACTIVE gates the microprocessor E clock through a U22 74HCT00 NAND which is buffered by U2...

Page 122: ......

Page 123: ...Principles of Operation 6 8...

Page 124: ...is selected This pulse occurs only once 3 The NEXTADDR line PB2 of VIA is set low This increments the counter and enables parallel loading of the parallel to serial converter 74HCTI65 NEXTADDR is kep...

Page 125: ...e valid relay control data has been sent to the cards and is present in the latches of the driver chips This action allows the relays to be controlled by the transmitted relay data information NOTE Th...

Page 126: ...Principles of Operation SOURCE DRIVERS Figure 6 8 Display board diagram 6 il...

Page 127: ...mn 5 DS28 DS29 Display Segments Display MUX columns 7 6 5 4 3 2 1 1 15 Alphanumeric digit 8 DS4 Alphanumeric digit 9 DS5 Alphanumeric digit 1 0 DS5 Alphanumeric digit 1 1 DS6 Alphanumeric digit 12 DS6...

Page 128: ...ssed As the display is multi plexed each key column is pulled low in its turn The other columns float Each row is connected to Vcc through a pull up resistor and to one of the inputs of parallel to se...

Page 129: ...n to get the byte of KEY DATA 8 Negate the low true KEY line 9 Configure the VIA shift register for output 6 6 Light pen interface The light pen interface circuitry resides on the digital board A simp...

Page 130: ...ans its display and gets no response from the light pen it instructs the slaves in turn to scan their displays Each slave monitors the U24 flip flop of the master to check whether or not the light pen...

Page 131: ...Principles of Operation Figure 6 11 Master slave interface simplified schematic 6 16...

Page 132: ...rt To cause the microprocessor to read the input lines the INLATCH signal is also routed to the CBl input of UlO 65C21 PIA which is programmed to generate an interrupt on a falling edge Digital output...

Page 133: ...Principles of Operation Figure 6 12 Digital I O interface simplified schematic...

Page 134: ...ng power supply Its 6 2V output is distributed to the backplane board for the relay coils of the switching cards and to the voltage regulator board The 5V output of the volt age regulator board is sup...

Page 135: ...area is compatible Perform the following steps to connect the power supply to the line power and turn it on 1 Before plugging in the power cord make sure the front panel power switch is in the off 0...

Page 136: ...installation Table 7 2 lists the necessary hardware for a fixed mounting of a Model 707A in a 19 wide rack 24 to 30 deep Verify that all parts are available before beginning the installation procedure...

Page 137: ...ng 6 Reinstall the chassis support assemblies in the rack and secure them to the captive nuts with binder head screws Also tighten the binder screws at the rear rack flange 7 Tighten the screws attach...

Page 138: ......

Page 139: ...om the instrument 1 With the Model 707A on a bench remove the front panel as follows A Place a thin book or other support under the unit to slightly raise the bottom edge of the front panel off the be...

Page 140: ...on occurs dean the board as described in paragraph 7 11 A Remove the backplane support bracket shown in Figure 7 6 B Unplug the following connections P33 Digital board ribbon cable connection to backp...

Page 141: ...he front panel swing it to the left approximately 45 and rest it on its edge CAUTION Do not touch the surface of the back plane to prevent possible contamination from body oil and dirt which could deg...

Page 142: ...Maintenance higure 7 7 Backplane jumpers Slots Slot 4 7 8...

Page 143: ...t side panel and handle 6 Reinstall the power line cord and turn on the Model 707A It will power up in random conditions such as make break and break make on the same rows 7 8 Static sensitive devices...

Page 144: ...being lit 7 9 3 Power supply checks Power supply voltages should be checked first to make sure they are within the required limits If the various operating voltages are not within the limits troubles...

Page 145: ...aveforms of steps 8 through 10 Low going pulses IkHz 2 U28 pin 5 CLRADDR High logic pulse at start of each matrix card ID byte transfer 3 U28 pin 3 NEXTADDR sequence on power up Low logic pulse before...

Page 146: ...pin3 KEYCLK sec Base frequency of 895kHz with one set of pulses every lin 5 TJ23 pin 6 DISPDATA sec See Figure 7 10 6 U23 pin 2 KEYDATA See Figure 7 10 Table 7 8 Digital I O checks Step Item component...

Page 147: ...en light pen button is pressed Table 7 10 Master slave checks Step Item component Signal Comments 1 U1 1 pins 3 4 RXCLK TXCLK The following digital board signals are referenced to digital common When...

Page 148: ...1 U13 pin 12 Source driver ITie following display board signals are referenced to digital common When troubleshooting the LED array check for these signals when the LED is lit e g crosspoint A 1 Card...

Page 149: ...TJTJTTLTLrLJ RELAYDATA DO Figure 7 9 Relay control waveforms Repeated every 1 msec 1 DISPCLK Repeated every 1 rnsec 1 895 kHz KEYCLK Repeated every 1 msec DISPDATA Irrsec KEY DATA 1rrs0C Figure 7 10 D...

Page 150: ...e not to spread the flux to other areas of the board 3 Once the flux has been removed swab only the repaired area with the methanol then blow dry the board with dry nitrogen gas 4 After cleaning the b...

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