VSAM USER`S MANUAL
Contents
1. volt power as noted above FRONT PANEL ANALOG CONNECTOR PIN OUT The Analog signal input connector is a standard DIN 96 male contact type with retaining screws The pin out is as follows CHAN INPUT INPUT CHAN INPUT INPUT 0 At A2 16 B17 B18 w 1 A3 A4 17 B19 B20 a 2 A5 A6 18 B21 B22 M 3 A7 A8 19 B23 B24 ma 4 A9 A10 20 B25 B26 Sa 5 A11 A12 21 B27 B28 Le 6 A17 A18 22 C1 C2 ge 7 A19 A20 23 C3 C4 is 8 A21 A22 24 C5 C6 Ba 9 A23 A24 25 C7 C8 ge 10 A25 A26 26 c9 C10 eta 11 A27 A28 27 C11 C12 ee 12 B1 B2 28 C17 C18 sx 13 B3 B4 29 C19 C20 14 B5 B6 30 C21 C22 15 B7 B8 31 C23 C24 The 10 240 volt reference and returns may be used to power external thermal couple ice point reference planes 10 240 VOLT REFERENCE through 5 1k 1 resistor B9 C25 10 240 VOLT RETURN B10 C26 Shields and grounds ANALOG RETURN B11 C27 GROUP SHIELD B12 C28 7 0 WARRANTY Equipment manufactured by Bi Ra Systems for use in the United States is warranted against defects in design workmanship and materials for a period of one 1 year from the date of shipment Bi Ra Systems will repair or replace at its option any such equipment found to be defective on a return to factory basis Repair charges will be applicable after the warranty period has expired Transportation charges for shipping the equipment to Bi Ra Systems shall be paid by the customer while transportation charges for the return of the repaired equipment will be paid by Bi Ra Sy2. of the analog voltages that is applied to the inputs e The second is that 99 999 volts value is readout on all channels immediately after reset or power up and when a calibration fails See the calibration section for details e The third is 50 00 volts value is readout on individual channels if the input voltage is changing too fast for the channel to be digitized The processor attempts to digitize the channel five times before it gives up and sends 50 00 volts to the channel buffer A good attempt is defined as one that the ADC is not at zero or full scale e The fourth data type is one that one or more channels read back 10 24 volts This is an indication that the input voltage is above 10 24 Channel Range Readout Starting at base address 80 hex are 32 bytes of channel range information R One byte is assigned per channel This information is used for diagnostic purposes to determine the range setting of the PGIA for each channel The values range from zero to ten where zero designates the 10 24 volt range one designates the 5 12 volt range and so on down to eleven which designates the 10 milli volt range The least significant byte is channel 0 the second least significant byte is channel one and so on The following table illustrates the channel range data format Channel Word 80 hex 3 2 1 0 Word 98 hex 27 26 25 24 Word 9C hex 31 30 29 28 Channel AC Component Readout AC measurement values are read out starting at base addres
3. MODEL VME 7305 VME Smart Analog Monitor VSAM 1 0 INTRODUCTION This manual is a brief user focused description of the VSAM VME Smart Analog Monitor Section 2 0 is a brief description of the VSAM s operation Section 3 describes the VSAM performance specifications Sections 5 0 through 7 0 describe the VSAM s power requirements Software and I O Connections VSAM is a VMEbus based compact 6U 1wide 32 channel micro computer controlled analog multiplexer A D converter module Figure 1 on the next page is a simplified VSAM Block Diagram Some components and connections have been omitted from this figure for simplicity Note that the block diagram s bus or multiple signal runs are indicated by wide lines single signal lines are unit width The block diagram shows the schematic diagram s IC numbers and bus labels The bus labels suggest the bus function and number of bus lines Thus AMP 0 3 indicates the 4 line amplifier gain control bus The analog components consist of 32 input low pass input RC filters a 32 channel differential mode analog signal multiplexer a calibration voltage reference a reference signal analog multiplexer and a programmable instrumentation amplifier PGIA The PGIA converts the differential input analog signal to a single ended signal that drives the 16 bit ADC The amplifier s high common mode rejection reduces the perturbing effects of common mode noise on the analog signals and has eleve
4. US USAGE The VSAM uses the Data Transfer Bus and the SYSRESET and SYSCLK signals in the Utility Bus The VSAM does not use the Data Transfer Arbitration Bus but the BGOIN through BG3IN lines are jumpered to BGOOUT through BG3OUT lines respectively for compatibility with other VMEbus units 4 that may use bus arbitration Similarly the VSAM does not use the Priority Interrupt Bus but the IACKIN line is jumpered to the IACKOUT line for compatibility with other VMEbus units that may use this bus VSAM Address The VMEbus address mode is A24 with the upper 16 bits selected by internal dip switches The VMEbus data format is D32 only Unless commanded by a little endian mode command data is stored in the VME Output Buffer memory in big endian mode the standard VMEbus mode Data can be stored in little endian mode by selecting the little endian bit in the command word as described in the Commands paragraph below SETTING THE BASE ADDRESS Address Set Switches locations SW1 and SW2 Set all address switches to ON except positions A20 amp A23 at SW2 this places the VSAM module at Base Address 900 000 Hex COMMANDS System Reset Writing to base address E0 Hex Two seconds after a reset or power on Valid data is available Mode Control Register Address Set Switches Write to address base E4 Hex y 20 DO 0 Normal channel scan DO 1 Fast channel scan D1 0 Normal analog channel data D1 1 Request firmwar
5. ange channel assignments The micro computer applies a linear calibration correction to each reading The coefficients are obtained from a calibration procedure that measures offset values for each gain range of the PGIA and an overall system gain effectively the gain of the ADC This procedure assumes the internal voltage reference REF0O1 has been accurately adjusted to 10 240 volts and the gain precision of the PGIA is better than 0 02 The calibration procedure is performed every ten seconds The processor determines the sign and range of a channel by requiring the ADC to operate in the upper half of its range If this condition is not met at any time during the signal averaging process the gain is corrected and the averaging restarted The microcomputer calibrates the VSAM about every ten seconds A 10 240 volt reference source and analog ground are multiplexed to the PGIA for calibration purposes The VSAM has two operating modes Normal Scan and Fast Scan In the normal scan mode 64 equally spaced readings are digitally filtered over 1 60 of a second Normal mode noise rejection at 60 Hz and its harmonics is at least 35DB The fast scan mode averages 8 readings in 2 milliseconds and does not provide normal mode 60 Hz noise rejection This mode provides faster response for tweaking purposes In the normal scan mode the processing time per channel is 23 ms consisting of 16 ms for digital filtering and 4 ms for correction and
6. annel data The gain correction factor is determined from the value read on the 10 24 reference channel The offset is removed from this channel and 10 24 is divided by this result Each channel value is multiplied by this correction constant A Calibration failure is reported by loading all 32 channels with 99 99 volts A calibration failure occurs if the digitized value of the 10 24 volt and zero volt references do not digitize to a reasonable value The 10 24 volt reference must be within 80 and 99 8 of full ADC value The zero volt reference must be greater than 3 and less than 3 of full scale since there is a built in offset of 1 5 of full scale Digital Filtering DC component Normal scan mode Each channel is averaged normal mode over 1 60 th of a second Sixty four samples are accumulated then divided by sixty four Normal mode rejection at 60 Hz and its harmonics is 35 dB minimum The time base is a 6 MHz crystal oscillator Fast scan mode Each channel is averaged normal mode over eight samples No normal mode 60 Hz rejection is provided Channel Refresh Rate Normal scan mode Each channel requires 23 milliseconds for processing The 20 milliseconds include 16 milli seconds for averaging and 4 for data correction formatting Total refresh rate for the 32 channels is 750 milliseconds The worst case refresh time is 2 seconds if all 32 channels see a large input step and polarity reversal Fast scan mode Each channel requi
7. d 152nV when R 10 The VSAM overall dynamic range including the eleven ranges is 26 bits eleven bits resulting from control of the PGIA gain and 15 uni polar bits from the ADC Temperature Sensitivity The VSAM maintains its specified accuracy between 0 and 50 degree Celsius DC Accuracy 0 1 of reading 20 micro volts on all ranges for the normal scan mode 0 2 of reading 40 micro volts on all ranges for the fast scan mode 0 01 of reading per month AC Measurements AC Measurement Resolution is 0 2 of DC voltage 60Hz Sensitivity decreases 6DB octave above 60Hz AC Measurement Accuracy is 20 of reading 3 3 SIGNAL PROCESSING Data Acquisition Mode The VSAM has two operating modes Normal Scan slow and Fast Scan Normal Scan is the usual operating mode Fast Scan provides faster output data response for tweaking purposes Mode selection influences data processing as described below Calibration The micro computer performs calibration using a linear correction scheme This scheme involves two assumptions 1 the on board reference supply is adjusted correctly and 2 the PGIA meets its 0 02 accuracy specification About every ten seconds the 10 24 and the zero volt references analog ground are sampled and converted The values of the zero volt reference for each gain setting of the PGIA are maintained in a look up table Offset correction is performed by subtracting the appropriate value from the converted ch
8. e VSAM 1 Base Address and Memory Space of the MXI board 2 Base Address of the VSAM board Data Format selection Data or Version Info and Scan Mode selection 3 GPIB Address of HP34401A 4 Base Address of the VSAM Tester Board Reference Voltage On Off selection Voltage Scale 0 1 1 or 10 Volts selection Desired Output Voltage or Desired DAC Setting AutoRange ON OFF and selection of the Bit Pattern for the 32 Channels 5 Operation selection Do VSAM Reset and Init Get VSAM Status Do VSAM Init Do VSAM Read Setup VSAM Tester and Read HP34401A Voltmeter VI Status VSAM Control Register DAC Value Hexadecimal DAC Value Decimal Readback of Reference Voltage using HP34401A and individual channel Value Diff from Ref Diff Range and Peak to Peak Voltage Variation AC Component This application VI uses a 0 05 accuracy compare for PASS FAIL criterion however the VSAM accuracy specification is 0 1 This VI can also be used as an isolated manipulator for the VSAM VSAM EPICS DRIVERS WEB LINK ftp ftp slac stanford edu groups controls soft epics LabView Software Development Link from SLAC http www slac stanford edu grp efd babar work files labview html HARDWARE National Instruments VME PCI8000 Series interface link is used to connect the PCI based co
9. e revision number The revision number is returned in all channels in floating point format D1 must be cleared to 0 to resume analog processing No AC processing is performed in this mode D3 0 Big endian mode byte zero contains the most significant byte the is standard VMEbus usage If D3 1 Little endian mode byte zero contains the least significant byte the standard PCI bus usage Status Register Read from address base E4 Hex DO DO 0Normal Scan DO 1 Fast scan mode D1 D1 0 Normal data presented in channel buffers D1 1 Z80 Firmware revision number is presented in channel buffers D2 D2 0 Big endian mode D2 1 Little endian mode D3 D8 1 Internal calibration successful D3 0 Internal calibration failed Diagnostic Test Mode Write to address base FO Hex This command forces the micro computer to halt This mode is used to permit the VME Output Buffer dual port memory to be tested from the VMEbus without interference from the micro computer A System Reset must be used to clear this mode DATA READOUT Channel DC Component Readout Each channel is allocated one long word 4 bytes in VME address space Channel 0 is assigned to VME base address 0 channel 1 assigned to VME base address 1 and so on through 31 There are four representations of the data that need to be considered The value of each channel should be categorized by the following criteria below e The first is normal data that is representative
10. esented to the VMEbus as single precision IEEE floating point in units of volts The floating point format is described in Section 3 4 The BUS ACTV LED flashes about 0 5 seconds for each VME cycle The OK LED flashes at one half the buffer update frequency provided that the calibration was successful and that the firmware revision wasn t requested and that the processor is not halted by the diagnostic mode 3 0 VSAM SPECIFICATIONS 3 1 ANALOG INPUT SPECIFICATIONS Thirty two differential analog input channels Channel input impedance at DC is twenty meg ohms Common mode low pass RC filter response is 3DB 10 KHz Maximum continuous DC voltage is 40 volts Maximum DC voltage for one second is 100 volts Input voltage normal mode plus common mode must be less than 10 3 volts for specified accuracy Common mode rejection between 0 and 60 Hz is 80 dB minimum The maximum source impedance normal mode is 2K ohm to attain the specified accuracy The maximum source impedance with an unbalanced common mode signal is a 100 ohms 3 2 ACCURACY SPECIFICATIONS Gain Ranges 10 mV to 10 24 volts full scale in 10 steps of 2X 11 gain values The PGIA manufacturer guarantees the gain error to be less than 0 02 for all gain ranges Maximum voltage difference between channels must be less than 40 dB to attain the specified accuracy DC Resolution amp Dynamic Range The DC resolution is to 15 bits for each range setting 300uV when R 0 an
11. formatting Thus the total refresh interval for the 32 channels is 0 75 seconds if no ranging or polarity changes occur The refresh time in fast scan mode is 0 30 seconds AC measurements are made continuously in both fast and normal scan modes but is most useful in normal scan mode since it can see 60 Hz components AC measurements are made to determine the level of contaminating AC on the analog signal For example if the channel is measuring the shunt voltage on a magnet power supply the AC measurement will check for a ripple component arising from a damaged filter section The measurement records the maximum peak to peak excursion of the input voltage during the signal processing time of 1 60th second The value N is stored in sixteen bit words as described in Section 3 3 The AC peak to peak voltage is Vpp 20 48 N 215 2 R 60Hz where N is an unsigned 15 bit number and R is the range byte associated to the given channel The normal mode RC input filter decreases the sensitivity of the AC measurement by 6DB octave above 60Hz The algorithm used for AC measurements may cause N to vary between 0 and 30 for a clean DC signal therefore values of N gt 30 are significant The sensitivity of the AC measurement is 0 2 of the DC voltage at 60 Hz The accuracy is 20 20 The 3 dB frequencies for the signal s normal differential component are about 33 Hz and about 10 kHz for the common mode component respectively Output data is pr
12. gain corrections which are applied to each channel s reading The micro computer s signal processing determines the analog signal s DC and normal mode 60 Hz noise components both are loaded into the VME Output Buffer The processor converts the data to floating point format and the data readout can be commanded to either big endian or little endian mode These features are described in more detail below In performing these smart functions the micro computer sequences through the 32 analog input channels measuring and storing each signal s DC and AC voltage components in the VME Output Buffer The measurement process consists of range acquisition digital signal averaging over one 60 Hz period to remove normal mode 60 Hz noise gain and offset correction and conversion of the data to floating point format The 16 bit ADC is configured in bipolar mode which is equivalent to 15 bits uni polar The overall dynamic range of the VSAM is 26 bits eleven bits resulting from control of the PGIA gain and 15 uni polar bits from the ADC The PGIA voltage gain R can be changed in 11 binary weighted values from 10 24 volts through 10mV R is an integer whose value may be 0 through 10 and is stored in the least significant four bits of each channels data readout value This information is useful for determining the resolution Vres and the full scale voltage Vfs of a given input signal Vres Vinput 2 15 2 R Vfs 10 24 2 R See section 3 2 for r
13. ity for such repair or replacement shall in no event exceed the contract price allocable to the products or part which gives rise to the claim BI RASYSTEMS SHALL IN NO EVENT BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES RETURN OF PRODUCTS Bi Ra Systems must be notified before any product is returned for any reason The Customer Service Department must issue a Return Material Authorization RMA number before any product can be accepted for credit exchange or repair In order to provide an RMA number Customer Service will need the complete model number serial number original purchase order number and details regarding the reason for return and the service required All returns for CREDIT or EXCHANGE are subject to Bi Ra Systems approval and will incur a minimum restocking charge of ten 10 percent as well as any incoming transportation charges or other fees incurred by Bi Ra Systems All returns for WARRANTY REPAIR must include a description of the problem and the name of a technical contact in case the problem must be discussed If the product is out of warranty the customer must contact Bi Ra Systems for an estimate of the repair charges and include a purchase order number for the estimated repair charges Transportation charges for shipping the products to Bi Ra Systems shall be paid by the customer Transportation charges for the return of the products that have be exchanged shall be paid by the customer while transportation charges fo
14. mputer directly to the VMEbus using the high speed Multisystem eXtension Interface bus MXI National Instruments PCI GPIB high performance Plug and Play IEEE 488 interface is used to link the computer to the HP 34401A a 6 1 2 digit high performance digital multimeter A SLAC designed VSAM Tester Module DAC is used to provide analog voltages to the VSAM via the front panel connector 1 Reference Voltage ON OFF 2 Reference Voltage Normal inverted 3 Voltage Scale 10 Volts 1 Volts 0 1 Volts 4 Data Format Big Endian Little Endian 5 Data or Version Info Data Version 6 Scan Mode Normal Fast 7 Operation Do VSAM Reset and Init Get VSAM Status Do VSAM Init Do VSAM Read Setup VSAM Tester Read HP34401A Voltmeter NOTE The VSAM Tester is a VME DAC that stimulates the VSAM via the Front Panel Connector 5 0 VSAM POWER REQUIREMENTS The VSAM uses 5 volts 1 4 amperes connected to the P1 and P2 5 VDC pins The VSAM does not use the bus and 12 volt power an internal DC to DC converter powered by 5 VDC provides the and 15 volt power required by the analog circuitry A 5 volt regulator provides the 5 volt power required by the ADC 6 0 I O CONNECTIONS VMEbus P1 AND P2 CONNECTOR PIN OUTS The VSAM conforms to the VME IEEE 1014 VMEbus specification The VSAM does not use some bus signals These are IACK IRQn 5STDBY and SYSFAIL VSAM does not use the bus and 12
15. n selectable high precision gain ranges As suggested by the name VSAM s internal micro computer performs Smart functions these are described below The micro computer components are a Z80 microprocessor a 16Kx8 EPROM program memory a 2Kx8 static RAM and the MUX ADC Control chip The micro computer reads the ADC data performs the signal processing and data formatting functions and stores the output data in the VME Output Buffer The MUX ADC Control chip controls the PGIA gain and analog and calibration multiplexers The VMEbus interface consists of address DIP switches address comparators a VMEbus Interface chip and the VME Output Buffer a 32 bit Dual Port RAM Buffer contents are read by VMEbus bus read operations The 32 analog input signals are connected to the module via a front panel 96 pin DIN connector Input signal pin assignments are listed in Section 6 A 6 MHz crystal oscillator is used as a time base Front panel activity indicators are BUS ACTV bus active and OK Z80 program execution active LEDs 2 0 VSAM OPERATION The VSAM s analog components are high performance devices however VSAM s performance is further enhanced by Smart functions performed by the micro computer These are digital filtering of the analog signals auto ranging gain adjustment to maximize conversion resolution operation over a 1000 1 dynamic range of the analog signals and periodic auto calibration to determine offset and
16. r the return of the repaired equipment will be paid by Bi Ra Systems The return shipment will be by UPS services air freight or truck Premium methods of shipment are available at the customer s expense and will be used only when requested If Bi Ra Systems selects the carrier Bi Ra Systems will not thereby assume any responsibility or liability in connection with the shipment nor shall the carrier be in any way construed to be the agent of Bi Ra Systems After obtaining a Return Material Authorization RMA number customers should return the product to BI RASYSTEMS INC 2404 COMANCHE NE ALBUQUERQUE NEW MEXICO 87107 TELEPHONE 505 881 8887 FAX 505 888 0651 SERVICES Contact Bi Ra Systems for details regarding the following services complete module design and development for both CAMAC and FASTBUS products this includes the design complete drafting package from schematic to artwork done on a CADNETICS INTERGRAPH CAE CAD System proto type development and testing and production level products Systems Integrated Installation On Site Warranty Repair Module Exchange Program Service Contracts Applications Software Support and Training Bi Ra Systems now has a new WEB PAGE address http www bira com E mail info bira com and we also provide a credit card service for Visa and Master card 10
17. res 4 milliseconds for processing Total refresh rate for 32 channels is 300 milliseconds AC Measurements The VSAM performs a crude measurement of the AC component of an input signal in both normal and fast scan modes but the AC measurement is most useful in normal scan mode since 60 Hz AC signals are measured in normal scan mode This function provides some indication of problems such as power supply ripple AC signal components are measured and recorded continuously The measurement records the maximum peak to peak excursion of the input voltage during the signal processing time The value N is stored in sixteen bit words as described in Section 3 4 The AC peak to peak input voltage is V p p 20 48 N 215 2 R 60Hz Where N is an unsigned 16 bit number and R is the range byte associated with the given channel R is the PGIA range value Residual values of N greater than 10 are significant on ranges of 5 and less and values of N greater than 30 on all other ranges While this measurement is rough AC signals of less than 3mV on ten volt signals are recorded and AC signals of less than 10uV on the most sensitive scale are recorded The measurement accuracy is 20 of the reading Range Information Gain range information is provided in the range byte as described in the Channel Range Readout paragraph below The R value may range from O to 10 The full scale voltage is 10 24 2 R 3 4 VMEbus COMMAND AND DATA READOUT SPECIFICATIONS B
18. rs or warranty date decals have been removed or altered In addition to the forgoing any application on site warranty will not apply i if prerequisite equipment as specified by Bi Ra Systems price list equipment specifications or contract s is missing or ii if the product or system has been installed by the purchaser without the supervision of or prior written approval of Bi Ra Systems Equipment may contain used parts which are equivalent to new in performance when used in the equipment BI RASYSTEMS MAKES NO WARRANTY OR MECHANTABLILITY OR FITNESS FOR A 9 PARTICULAR PURPOSE OR ANY OTHER WARRANTY EITHER EXPRESS OR IMPLIED EXCEPT AS IS EXPRESSLY SET FORTH HEREIN Outside the United States the equipment warranty is limited to the replacement of the equipment and excludes shipping insurance taxes forwarders fees customs or any other charges THE WARRANTY PERIOD MAY VARY IN COUNTRIES OUTSIDE THE UNITED STATES CONTACT BI RA SYSTEMS OR YOUR LOCAL AUTHORIZED DISTRIBUTOR FOR SPECIFIC WARRANTY DETAILS LIMITATIONS OF LIABILITY The purchaser s exclusive remedy or any claim of any kind for loan or damage connected with or resulting from the design manufacture sale delivery resale or repair or use of any products furnished by Bi Ra Systems including but not limited to any claim of negligence or other breach shall be the repair or replacement F O B factory of the product or part thereof giving rise to such claim Bi Ra Systems liabil
19. s A0 hex One 2 byte word is used for each channel This range information must be read out in D32 mode two channels per D32 word and unpacked in software This information is used for diagnostic purposes to determine the AC component of the input signal The AC peak to peak voltage is V p p 20 48 N 215 2 R 60Hz Where N is an unsigned 16 bit number as shown in the following table and R is the range byte associated with a given channel as described in the Channel Range Readout paragraph above Residual values of N greater than 10 are significant on ranges of 5 and less and values of N greater than 30 on all other ranges While this measurement is rough AC signals of less than 3mV on ten volt signals are recorded and AC signals of less than 10uV on the most sensitive scale are recorded The measurement accuracy is 20 of reading The following table illustrates the channel AC component readout format Channel Word AO hex 1 0 Word D8 hex 29 28 Word DC hex 31 30 IEEE SINGLE PRECISION FLOATING POINT FORMAT D31 sign bit S 0 positive 1 negative D30 24 exponent EXP D22 0 mantissa The value S 2 EXP 127 1 MANTISSA D D D D D 3 3 2 2 0 1 0 3 2 0 S EXP MANTISSA 4 0 VSAM SOFTWARE SOFTWARE 6 This software uses LabVIEW Version 4 1 and is a Windows 95 application written by Mr Perry Anthony VSAM And VSAMTester Manipulation VI has five basic blocks that are used to test th
20. stems Priority shipping methods are available at the customer s expense SOFTWARE products by Bi Ra Systems are furnished under the terms and conditions of a separate Software Product License Agreement is warranted for a period of ninety 90 days from the date of shipment to conform to the Software Product Description SPD applicable at the time of purchase This warranty is contingent upon the proper use of the software as detailed in the Software Product License Agreement and is limited to the remedy of any non conformance of the Software to the SPD PRODUCTS PURCHASED BY BI RASYSTEMS FOR RESALE WILL CARRY THE ORIGINAL EQUIPMENT MANUFACTURER S WARRANTY IF ANY These warranties shall not apply to equipment or software that has been modified or serviced by other than a Bi Ra Systems or an authorized distributor service engineer All warranties are contingent upon proper use of the product or system These warranties will not apply i if adjustment repair or parts replacement is required because of accident unusual physical electrical or electro magnetic stress neglect misuse failure of electric power air conditioning humidity control transportation failure to rotating media not furnished by Bi Ra Systems operation with media not meeting or not maintained in accordance with Bi Ra Systems specification or causes other than ordinary use or ii if the product or system has been modified by the purchaser or iii where Bi Ra Systems serial numbe
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