SUPER Help

Getting_started

Words in caps are other help keywords. To move a single motor, the name of the motor plus its new absolute position is sufficient (MOVE). LINEUP scans are used to move a single motor around the present position. SETUP is used to define scans. SCAN #,#,# will scan whichever of the 20 scans you have defined in SETUP. In SETUP, scan types include ANGLE, MOTOR, ENERGY, XSCAN, INTEGER, TIME, SIMULTANEOUS, KSCAN, HSCAN. There is now a log file (NOTE) which records significant changes to the system. The parallel program SPLOT will plot the current scan (during the scan) or previous scans. Fitting of peaks (Gauss,Lorenz, Wertheim) available in SPLOT. SETUP, CALC, INVERS and NOTE are also active in SPLOT.

ABORT

^C (control C). This will stop all motors from moving. It will also abort a count if typed during a scan, without loss of data. Note that while the 4 diffractometer motors have ramp-downs on abort, the mono and table do not, so you are likely to lose steps if you abort a mono move. In general it is better not to abort a move if possible.

ABSORBER

One can have the computer monitor the data rate being collected by the I detector. If it exceeds a certain value the computer will insert a filter (If there is pneumatic filter cartidge mounted on the 2THETA arm of the diffractometer) and retake that data point. The computer also writes an integer corresponding to the positions of the filters as the last of the hex scaler values at each data point in the data file. When used without qualifier the command is a logical switch. When modified, it changes the parameter but doesn't change the logical switch setting. Thus typing ABSORBER will alternately enable and disable the feature, but ABSORBER/RATE=40000 will change the maximum count rate without changing whether the computer will actuate the absorbers or not. NOTE: ABS/SCALE is now COUNT/CALCULATED.

ABSORBER :

Manual_use

The absorbers can also be inserted manually using the paddle switches on the NIM module. The paddle switches and the computer control are ORed for the inserted position. One might want to set the absorbers manually and still record their positions without having the computer add additional absorbers. The way to achieve this is to disable ABSORBER and type COUNT/REGISTER, which reads channel 0 of the quad input register when it reads the hexscaler and stores the value at each data point. The filters are channels 17-20 of the input register. Of course, the computer thinks that channel 17 is actually 16, so having the first filter in results in an integer value of 65536.

ABSORBER :

Hardware

Channels 17-20 of the quad input register are tied to the 4 filter positions. A 1 in any of those positions corresponds to that filter being inserted, either under computer control or manually. Similarly, channels 17-20 of the output register are used to set the absorbers when under computer control. Of course, the computer thinks that channel 17 is actually 16, so having the first filter in results in an integer value of 65536.

ABSORBER :

Qualifiers

ABSORBER :

/ON

For those who don't remember the state of the ABS logical switch, one can explicitly set turn on automatic filter insertion with /ON.

ABSORBER :

/OFF

For those who don't remember the state of the ABS logical switch, one can explicitly set turn off automatic filter insertion with /OFF.

ABSORBER :

/CHANNEL

Which Hex scaler channel (1-6) should be used to determine the maximum count rate. Most of the time this should be channel 1, as that is assumed to be the I signal by other parts of the program. The only time you wouldn't use channel 1 is if you were using a solid state detector and wanted the elastic signal in channel 1 and the total signal in another channel. You would then monitor the total signal for insertion of filters. Note: For calculating the actual count rate (see count/calc) channel 1 is always used.

ABSORBER :

/DELAY

Set the delay time after inserting a filter before continuing. The default time has been recently (4/17/96) been set to 0.35 seconds, but can now be adjusted by this command. The problem is that the filter is set merely by setting some TTL levels, and the actuation of the pistons takes longer than that. Syntax: ABS/DELAY 0.35

ABSORBER :

/INSERT

This tells the computer to insert one or more filters. The parameter should set a 1 for an inserted filter and a zero, so ABS/INS 1010 would insert filters 1 and 3. Why is this command here? It may come in handy for indirect command files, for one. Also, it is logged to SUPER.LOG, which helps bookeeping.

ABSORBER :

/LENGTH

Define the absorption lengths for the particular set of filters you are using. Syntax: ABSORBER/LENGTH 1,10,100,1000 would tell the program that the absorbers in the filter set are 1 e-length, 10 e-lengths, etc. An e-length is the thickness which would reduce the intensity by 63%. Note that the e-lengths are energy dependent, so you should confirm that the values are correct for your photon energy. A good estimate of the length can be obtained using the ABSORPTION program, which should be installed on this machine and is definitely on SSRL.

ABSORBER :

/RATE

Defines the count rate above which the computer will try to reduce the rate by inserting a filter. It will iterate on the same data point until it has either reduced the count rate below the defined value or inserted all 4 filters. Syntax: ABSORBER/RATE 40000 which sets the maximum count rate to 40000 counts per second. When the count rate drops below 0.9*max_rate the program will recalculate the proper number of absorbers NOTE: The program assumes that the absorbers are installed in ascending order of thickness, i.e. the thinnest filter is listed first. Otherwise it won't calculate the right combination of filters to insert.

ABSORBER :

/SCALE

This has been replaced by COUNT/CALCULATED. In it's new version it can be turned on whether or not ABSORBER mode is turned on. Writes to disk (and screen) a scaled version of the signal as the last channel.

ADC

This will use a LeCroy 3512 ADC with a 3588 histogramming memory OR a XIA DXP module(s). If turned on, then any count will collect data from the ADC in addition to the hex scaler. Scans will also write a spectrum to disk for each data point. For a scan name of TEST.043, the ADC spectra will be TEST043_##.001->N, where ## is the element number. Lecroy modules aren't defined in bl_define.def, but in ls:define_slots.com

ADC :

Hist_Switches

Remember that the Histogram DIP switches are different for the ADC and TDC modules. The two choices are listed in the "Using the 3588 Data Bus" manual. Briefly, for the ADC you want the middle 4 rockers open (depressed on the right, looking at the back of the module).

ADC :

Qualifiers

ADC :

/BOTH

Save the adc spectrum both as a histogram and as regions of interest (ROI)'s defined using the ADC/ROI command. Alternatives are SPECTRUM and CHANNELS. For the DXP, SPECTRUM= BOTH.

ADC :

/CHANNELS

Save the data as integrals of regions of interest (ROI)'s defined using the ADC/ROI command. In this mode the entire histogram is NOT saved, only the ROI's. Alternatives are SPECTRUM and BOTH.

ADC :

/ON

Turns on the ADC mode.

ADC :

/OFF

Turns off the ADC mode.

ADC :

/END

Last channel to be plotted and recorded to disk. From 2 to 8192. For the DXP, max= 1024.

ADC :

/DISPLAY

For the DXP, changes which element is plotted after a count, and displays the current data for that element. Thus, after a count, you can review the data collected by multiple elements. Remember, though, that the last element viewed is the new default element for plotting after the next count. Example: ADC/DISPLAY/CHAN=channel

ADC :

/GAIN

The digitizing resolution. Choices are 250,500,1000,2000,4000,8000. A gain of 1000 puts an 8 volt signal at channel 1000. Only valid for the Lecroy 3588.

ADC :

/LOGROI

This will list the current ROI's for all the elements as well as write them to SUPER.LOG.

ADC :

/REFRESH

During a long count one can see the spectrum that has been collected. This defines the wait (in seconds) between plots. This is the same variable that is used in UPDATE/REPEAT=X, so it can be changed with that command as well.

ADC :

/ROI

Defines the first region_of_interest. This is the same as /1ROI

ADC :

/1ROI

Defines the first region_of_interest. Parameters are element #, starting bin, ending bin. If no parameters are given, a list of the ROI's for all elements is given. If 0 is given as the element number, then the start and stop bins are set the same for all elements. Example: ADC/1ROI 7,200,300 sets the first roi for element 7 from 200 to 300. ADC/ROI is equivalent.

ADC :

/2ROI

Defines the second region_of_interest. Parameters are element #, starting bin, ending bin. If no parameters are given, a list of the ROI's for all elements is given. If 0 is given as the element number, then the start and stop bins are set the same for all elements. Example: ADC/2ROI 7,200,300 sets the second roi for element 7 from 200 to 300.

ADC :

/3ROI

Defines the third region_of_interest. Parameters are element #, starting bin, ending bin. If no parameters are given, a list of the ROI's for all elements is given. If 0 is given as the element number, then the start and stop bins are set the same for all elements. Example: ADC/3ROI 7,200,300 sets the third roi for element 7 from 200 to 300.

ADC :

/SAVE

Saves the spectra collected with the most recent COUNT. Only saves channels between those defined by /START and /END. Also writes the hexscaler data at the top of the file. For the DXP, it also writes the DXP parameters ICR, OCR, Live_time (msec), SCA1, BG1, SCA2, BG2, SCA3,BG3. These parameters are the last nine of the hex scaler list.

ADC :

/SPECTRUM

The data collected by the ADC are saved as a histogram only, i.e. no regions of interest (ROI)'s are saved from the data. Alternatives are CHANNELS and BOTH. For the DXP module, SPECTRUM is the same as BOTH.

ADC :

/START

Starting channel to be plotted and recorded. From 1 to 8191. For the DXP module, start can be from 1- 1023.

ADC :

/DXPALIGN

This command serve two purposes: it set the DXP gains in such a way that the most frequent energy in the spectrum is converted into the requested channel of the internal ADC (this is known as the DXP "adc rule", typical adc rule values are between 5% and 10% of the ADC full scale), then it adjusts theveryfinegain so that all channels display the peak in the same MCA channel. It expects the energy of the most intense line in the spectrum, the adc rule (default is 5), and the acuisition time to be used in each iteration. Example: ADC/DXPALIGN Energy AdcRule Time/Iteration

ADC :

/DXPCALIBRATE

This run sequentially the RESET and TRACKRST calibration to ALL the DXP modules. The RESET calibration measure the pre-amp reset voltage range and find the input voltages in term of tracking DAC settings and computes the correct value for the parameter OFFDACVAL (the DAC Offset).The TRACKRST calibration measure the correct value to be set on the tracking DAC after a preamplifier reset (TRACKRST ~= standard "reset" voltage). Example: ADC/DXPCAL

ADC :

/DXPFWHM

This calculates the FWHM of the LARGEST peak in the last acquired DXP spectra. It requires the peak energy (default is Cu Kalpha 8048 eV) to convert the FWHM in channel into FWHM in eV. If the channel specified is 0 it will calculates it for all channels. If no arguments are given it will prompt for the calibration energy and it will calculate FWHM for all channels The output from DXPFWHM is also written to SUPER.LOG. Example: ADC/DXPFWHM Chan Energy

ADC :

/DXPFF

Set or read the DXP Fast Filter parameters. To SET the DXP Fast Filter parameters it expects an element # and 4 arguments. The parameters are respectively FASTLEN FASTGAP MINWIDTH MAXWIDTH. They represent respectively: the lenght of the Fast Filter averaging interval in 50 ns unit, the lenght of the gap of the Fast Filter in 50 ns unit, the minimum width a pulse must have to be accepted as a real pulse and not just a noise spike, the maximum width a pulse should not exceed to be accepted as single pulse instead of piled-up pulse. A reasonnable set to start with is Fastlen=4, Fastgap=0, Minwidth=3, Maxwidth=16. If the element number is 0 the same values are set for all elements. Example: ADC/DXPFF chan Fastlen Fastgap Minwidth Maxwidth To READ the current parameters, NO ARGUMENT is needed. You will get a listing of the current values for all elements. Example: ADC/DXPFF

ADC :

/DXPGAIN

Set or read the DXP Gain parameters. To SET the DXP gains parameters it expects an element # and 3 arguments. The parameters are respectively COARSEGAIN,FINEGAIN and VRYFINGAIN.See the DXP user manual to determine reasonnable gain settings for the preamplifer you are using. If the element number is 0 the same values are set for all elements. Example: ADC/DXPGAIN chan Coarsegain Finegain Vryfinegain To READ the current parameters, NO ARGUMENT is needed. You will get a listing of the current values for all elements. Example: ADC/DXPGAIN

ADC :

/DXPINIT

It download the FiPPi instruction for the requested decimation and the DSP executable code. After the DSP code is downloaded even if most parameters will not be erased from the DSP memory some will be set differently (e.g. the gains). Once parameters are reset to reasonnable value the DXP needs to be recalibrated (e.g. ADC/DXPCAL). Example: ADC/DXPINIT

ADC :

/DXPLOAD

This will load a new DXP.CONFIG file. Whichever file you enter, it first copies that file to your sys$login: directory, renaming it to DXP.CONFIG, then loads the file. You can give a path to the file if it isn't in your current default directory. Example: ADC/DXPLOAD SSRL$LOCAL:[DXP]CUEDGE_80KPS.CONFIG will copy that file to sys$login:, renaming it to DXP.CONFIG, and load that into the modules.

ADC :

/DXPMCA

Set or read the DXP MCA parameters. To SET the DXP MCA parameters it expects an element # and 2 argument. The parameters are respectively MCALOWBIN and BINPERADC. MCALOWBIN allows the spectrum to be offset (i.e. binning to start at some x-ray energy value other than zero). BINPERADC contorls the DSP conversion of the pulse height calculated in the FiPPi to the appropriate MCA bin. See DXP user manual for details on how to set this parameter. Typical values are 4096, 8192 and 16384. If the element number is 0 the same values are set for all elements. Example: ADC/DXPMCA chan Mcalowbin Binperadc To READ the current parameters, NO ARGUMENT is needed. You will get a listing of the current values for all elements. Example: ADC/DXPMCA

ADC :

/DXPPEAK

Set or read the peaking time of the DSP. To SET the peaking time 3 arguments are needed: the element number, the desired peaking time PkTime in musec, and the RiseTime of the preamplifier pulse in musec. If the requested risetime is -1 the program will assume a reasonnable value for risetime. The slow filter parameters are calculated from: PkTime(musec)=0.5*(2*SLOWLEN+SLOWGAP)*(2**DECIMATION)*.050 Risetime(musec)=SLOWGAP*(2**DECIMATION) PEAKINT=SLOWLEN+SLOWGAP (for DECIMATION =0) PEAKINT=SLOWLEN+SLOWGAP+1 (for DECIMATION =2 or 4) PEAKSAMP=SLOWLEN+SLOWGAP/2-2 (for DECIMATION=0) PEAKSAMP=SLOWLEN+SLOWGAP/2-1 (for DECIMATION=2) PEAKSAMP=SLOWLEN+SLOWGAP/2+1 (for DECIMATION=4) A DXP calibration should be run after the program as reset the values (i.e. ADC/DXPCAL) To READ the peaking time NO ARGUMENT is needed. You will get a listing of the current values for all elements.

ADC :

/DXPREAD

Read a generic DXP parameter. This expects the element # and the name of the parameter. If the element number is 0, you get the values of that parameter for all the elements.

ADC :

/DXPSET

Set a generic DXP parameter. This expects the element #, the name of the parameter and the new value. If the element # is 0, you set the value of that parameter for all the elements.

ADC :

/DXPSF

Set or read the DXP Slow Filter parameters. To SET the DXP Slow Filter parameters it expects an element # and 4 argument. The parameters are respectively SLOWLEN SLOWGAP PEAKINT PEAKSAMP. They represent respectively: the lenght of the Slow Filter averaging interval in 50*(2**DECIMATION) ns unit, the lenght of the gap of the Slowfilter Filter in 50*(2**DECIMATION) ns unit, the inspection interval time for slow channel pulse pile-up, the time interval for slow channel data capture in the FiPPi. A reasonnable set to start with can be obtained from ADC/DXPPEAK. If the element number is 0 the same values are set for all elements. Example: ADC/DXPSF chan Slowgap Slowlen Peakint Peaksamp To READ the current parameters, NO ARGUMENT is needed. You will get a listing of the current values for all elements. Example: ADC/DXPSF

ADC :

/DXPTHRESHOLD

Set or read the DXP energy Threshold parameter. To SET the DXP threshold parameter it expects an element # and 1 argument. A reasonnable set to start with is THRESHOLD = 30. If the element number is 0 the same values are set for all elements. Example: ADC/DXPTHRS chan Threshold To READ the current parameters, NO ARGUMENT is needed. You will get a listing of the current values for all elements. Example: ADC/DXPTHRs

ADC :

/DXPWIN

Display the ROIs in the spectrum, either as a coincidence (i.e. display only the contents of the bin that are within the ROI) or an anticoincidence (i.e. display only the contents of the bin that are not in the ROI). This expects the element # the gate chosen (0= ANTICOINCIDENCE 1= COINCIDENCE) and the roi chosen.

ADC :

/DXPWRITE

This will save the current DXP configuration file to disk, with the name you give it. That way if you have a set or ROI's that you like or you have tweaked a parameter you can save your work for next time. Example: ADC/DXPWRITE MY_BEAUTIFUL_ROIS.CONFIG

ADC :

/DXPYMEM

This command can be used to read the 0:512 Y memory area. The y-memory area will contain two different sets of information depending on what you have done prior to the DXPYMEM command. If you perform a COUNT first, the y-memory will contain the baseline histogram, but if you perform a ADC/DXPOFFSET, the y-memory will contain the offset(OFFDACVAL) histogram. When the system is working properly the baseline spectrum should be essentially Gaussian in nature since it represent the electronic noise spectrum of the preamplifier/ ASC (Analog Signal Conditioner - the input stage of the DXP module). It is useful to compute the FWHM of the baseline histogram as it is a measure of the electronic noise (use FIT to compute FWHM). The FWHM in channel can be converted to eV using the formula: FWHM(eV)=FWHM(channels)*(BINPERADC*SLOWLEN)/1728. There are two different uses of DXPYMEM, depending on your need: SUP> COUNT 1 SUP> ADC/DXPYMEM channel SUP> FIT For the ADC/DXPOFFSET case, the histogram will be centered if the OFFDACVAL parameter has been selected properly. Increasing the OFFDACVAL will shift the histogram towards lower values. Example: SUP> ADC/DXPOFFSET SUP> ADC/DXPYMEM channel

ADDFIL

Will add files together and write the sum out as a file. Useful primarily for EXAFS data. Just keep giving a file name at the prompt. When done, type CtrlZ and the sum file will be written with the name of the first file to be summed with an S appended to the extension, ie fred.028s. Note that the header of the resulting file is that of the last file to be summed, so one can get a sense of the extent of the files summed.

/ADC

Add ADC spectra. An S is appended to the extension of the first file summed.

/TDC

Add TDC spectra. An S is appended to the extension of the first file summed.

/EXAFSPAK

Write the output of the summing in a binary file format which can be read by Graham George's EXAFSPAK. The columns of data are just as they are in the SUPER file, energy followed by hex channel 1->n. The output file name is that of the first file with the extension changed to XAS, e.g. fred028.xas.

/CONCATENATE

Appends the contents of a second file to a first one. In case you want to make one very long file from several short ones. Note that Super/Splot can plot up to 16000 data, so if you concatenate a file longer than that you can no longer plot it in super.

ANGLE

Angle move combines a 2THETA and a THETA move. One must specify the new absolute scaled position of both motors, even if only one will move. The first specified angle is the 2THETA angle, the second is THETA. The syntax is ANGLE 15.,7.

ASSIGN

This is used to tell the program which motors to display on the screen. One can also change the number of digits after the decimal point with this facility. Certain motor names can cause problems. A motor name supercedes a command verb, so if you name a motor 'DISPLAY' you'll have a hard time plotting the data. Also motor names PSI,HVAL,KVAL,LVAL and RADIAL are dealt with in a non-standard way, so don't call your motors by those names unless you know what you're doing. You can have up to 24 motors in three banks of 8. If you want to have a combination motor as well as component motors assigned, always assign the combination motor (e.g. MONO) first. You can also change individual motors by using qualifiers (see below).

ASSIGN :

Qualifiers

ASSIGN :

/ADD

To append a motor onto the current list, use /ADD. The required fields are the FULL name of the new motor and the number of significant digits beyond the decimal. Thus SUP> ASSIGN/ADD HORZ 3 will add the HORZ motor and give it 3 digits after the decimal.

ASSIGN :

/INSERT

You can insert a motor into the existing list with the /INSERT command. In this case you need to give the position (1-24) where the new motor should be, the FULL name of the motor, and the number of significant digits beyond the decimal. Thus SUP> ASSIGN/INSERT 4,HORZ,3 will insert HORZ as the 4th motor, pushing the current 4-n motors up to 5-n+1.

ASSIGN :

/REMOVE

This will remove a motor from the list. You need only tell the program the name of the motor, e.g. SUP> ASSIGN/REMOVE HORZ

ASSIGN :

/REPLACE

This will replace a motor with a new motor. You need to tell it the position of the existing motor, the FULL name of the new motor, and the number of significant digits for the new motor, e.g. SUP> ASSIGN/REPLACE 5,VERT,3 will replace whoever is motor #5 with the VERT motor.

BACKLASH

To change the value of the motor backlash, type MOTOR_NAME/BACK new_val. The sign of the backlash is such that of the move removing the backlash, thus a positive backlash is employed on negative moves. For more information, see HELP MOVE.

BITPATTERN

This sets a bit pattern in Channel 0 of the Quad Output Register. Type the 1 and 0 settings for pins 1-16, e.g. BITPAT 110100011 sets pins 1,2,4,8,9 of channel 0 to be 0 Volts. All the other settings will be +5V. On some beam lines there is a patch panel from the output register which make the connections simple to make.

BRAGG

Bragg move moves the diffractometer motors to the H,K,L value entered as parameters in the command. The syntax is BRAGG 1.4,0.,0. If in PSI mode, BRAGG expects an angle as well, i.e. 0,0,2,30 means move to a 0,0,2 reflection with a PSI angle of 30 degrees.

BRAGG :

Qualifiers

BRAGG :

/ANGLE

to move all the diffractometer motors. In this case instead of entering HKL enter 2theta,theta,chi,phi.

BRAGG :

/YMAX

Move to the xvalue corresponding to the maximum of the previous scan. Not implemented for all scans.

BRAGG :

/CENTROID

Move to the xvalue corresponding to the centroid of the previous scan. Not implemented for all scans.

CALCULATE

Calculate the angles corresponding to a given h,k,l Syntax: CALCULATE 2,2,0 Note: calculate depends on what calculation mode the program is in. Which mode is listed on the screen next to the reciprocal lattice vector. See verb MODE for the different calculation choices. Note that if the PSI motor is inserted one needs to specify that in addition to the h,k,l values.

CALCULATE :

Qualifiers

CALCULATE :

/DSPACE

Will calculate the spacing between planes of a given h,k,l Syntax: CALCULATE/DSPACE 2 2 0

CHANNELS

To change the number of hex scaler channels recorded by the program, type COUNT/CHANNEL new_value.

CI

This is a synonym for INVERSECALCULATE

CIS

Do a constant initial state (CIS) scan. The input parameters are the Monochromator starting energy, the CMA starting energy (the difference being the initial state energy), The step-size (in eV), the number of points, and optionally, the time per point. If the time is omitted the default count time is used. This scan will only work if both MONO and CMA are assigned motors in your version of SUPER (See ASSIGN).

CLEAR

Clears the screen and updates the motor positions in the non-scrolling region.

COUNT

Count measures the countrate entering the detectors for the period specified by the TIME parameter (or entered with the count command) and the count mode. The count mode is one of /DOSE,/TIME,/ROCK. "Time" is interpreted differently for the three count modes, see the help for those qualifiers to understand the differences. When turning on a qualifier (e.g. /AUTO) the program will execute a count unless the /NOCOUNT qualifier is added. When turning off a qualifier (e.g. /NOSETBIT) a count is not executed. Exceptions are /SCALERS (/CHANNELS) and /READBIT, where counts do not occur.

COUNT :

More_than_one_hexscaler

If you are collecting data from more than one hexscaler, there is the problem of putting out the data to an 80 character screen. What I have chosen to do is to truncate the number of channels that are printed on the screen so that the lines don't wrap. On disk, of course, all the channels are written. Also, if LOG is turned on, all channels are written to SUPER.LOG.

COUNT :

Qualifiers

COUNT :

/AUTOMATIC

IF you have two clocks and you turn this switch on, then the program will interpret a "time" less than 10 seconds as seconds, and count in TIME mode, and a "time" of more than 10 seconds as a dose and count in DOSE mode. To turn this off, type COUNT/NOAUTOMATIC.

COUNT :

/BASE

Changes the time base which is used to convert hexscaler pulses to time. No count occurs when this command is entered. The syntax is COUNT/BASE 1000 If the output of the realtime clock is used as the input for the time count the BASE value is 262144. Note that the Hexscaler input must be changed to NIM if the signal will be collected directly from the RTC clock output.

COUNT :

/CALCULATED

This is a logical switch which, if turned on, will write the calculated actual count rate as the last column rather than the register data. It takes the count from channel 1 (ALWAYS!) and calculates the actual rate based on the absorption lengths you have entered. Thus, be sure to get them right. If the calculated rate exceeds 2E9 counts, the value printed (and written to disk) is negative and divided by 1.e6. Thus, a value of -34567 is actualy 34.567e9 counts. The plotting package knows how to interpret such numbers, so plots will appear normally. Turn off with COUNT/NOCALC

COUNT :

/CHANNELS

Changes the number of channels that will be read. Does not actually perform a count for this command. This is synonymous with /SCALERS. The syntax is COUNT/CHANNELS 4 Note, this value is independent of whether the input register is being recorded as well. One can have up to 42 channnels (given 7 hex scalers). For scattering experiments, channel 1 is expected to be the detector signal, Channel 2 is expected to be the time, Channel 3 is the monitor channel.

COUNT :

/DARK

This is used to measure the dark current for ion chambers. It will prompt you to hit a carriage return (after you close the shutter) and then will count. If you enter a time for this measurement it won't become the default count time. The data are recorded on disk as a count rate (signal/second), just as they are reported on the screen. This is also a logical switch for writing these offsets to disk at the top of the file just after the starting motor positions. To turn off this option, type COUNT/NODARK. NOTE: COUNT/OFFSET will subtract offsets from the data BEFORE writing to disk.

COUNT :

/DOSE

Tells the computer that you are counting for a # of pulses. This is recorded in the data file. Alternatives are TIME and ROCK. In this mode the input to the realtimeclock module (RTC) is from the I0 detector. For many beam lines there are 2 clocks, one for I0, the other for time. Time is interpreted as follows: 14= 1x10^4 monitor counts, 35= 3x10^5 monitor counts. Minimum is 11.

COUNT :

/OFFSET

This is a logical switch for subtracting offsets (determined with COUNT/DARK) from the data prior to writing to disk. To turn off, type COUNT/NOOFFSET. To set the offsets, use COUNT/DARK. The two switches are independent, i.e. one can either write offsets at the top of the file or subtract them from the data or both. Offsets are recorded on a per-second basis. If /OFFSET is turned on and a scan is performed in DOSE mode, the results will be incorrect.

COUNT :

/LOG

This is a logical switch which writes the results of a COUNT to SUPER.LOG. The first line is a time stamp, and the reciprocal lattice position (if any). The second line is the position of all the motors. The third line is the hex scaler values. Turn off with /NOLOG.

COUNT :

/NOADC

Turns off counting of the ADC for this one count.

COUNT :

/NOCOUNT

This will override the count when setting switches, e.g. COUNT/SETBIT/AUTO/NOCOUNT will turn on SETBIT and AUTOMATIC without executing a count.

COUNT :

/PAUSE

Sets the time delay after a move has finished before the counting starts. The default is 0.25 seconds. This delay allows for settling of the monochromator. Syntax: COUNT/PAUSE 0.25

COUNT :

/READBIT

With this set rather than counting for a certain dose or time counting will continue UNTIL a logical true is sent to the second bit of the input register. (TTL true= 0 Volts). This overrides the /TIME,/DOSE, or /ROCK switches. This can be used to handshake with an external device which is doing the data collection. (SEE /SETBIT). A count does not occur when this is turned on or off. To turn off, use COUNT/NOREADBIT.

COUNT :

/REGISTER

This command tells the program there is a quad input register in the CAMAC crate and that the zeroth register should be read and translated into an integer value and recorded as data. The logical QIR$1 needs to be defined to be the correct slot number. The program adds one to the number of scalers in the system. The integer value written to disk is the sum of 2^n for each input. On some beam lines there is a patch panel which connects a buss bar to the register, so merely connecting your inputs to the buss bar will suffice. A logical 1 is 0V, so your device should ground the input when it is "on". The filters are channels 17-20. Of course, the computer thinks that channel 17 is actually 16, so having the first filter in results in an integer value of 65536. Turn off with COUNT/NOREG

COUNT :

/ROCK

Tells the computer that you are counting while moving a motor. This is recorded in the data file. Alternatives are DOSE and TIME. The program will prompt you which motor it will rock if you don't include the motor in the command line. In ROCK mode the TIME value is parsed as follows. If the "time" is 25, then the hexscalers will collect data while the motor scans +/- 1 degree about the center position for 5 iterations. An iteration is defined as move positive 1/2 the value, move negative the full value, then move positive 1/2 the value again. Thus 5 iterations is actually 9 full sweeps back and forth and a 1/2 sweep to start and finish the move. After the motor has stopped moving, the hexscaler stops counting. There are small variations in time of counting, but by looking at I/I0 the signal should be properly normalized.

COUNT :

/SCALERS

Changes the number of channels that will be read. Does not actually perform a count for this command. This is synonymous with /CHANNELS. The syntax is COUNT/SCALERS 4 Note, this value is independent of whether the input register is being recorded as well. One can have up to 42 channnels (given 7 hex scalers). For scattering experiments, channel 1 is expected to be the detector signal, Channel 2 is expected to be the time, Channel 3 is the monitor channel.

COUNT :

/SCATTER

This changes whether the second channel of the hexscaler is reported as a "time" rather than as counts. To report as counts, type COUNT/NOSCATTER; to report as time, type COUNT/SCATTER.

COUNT :

/SETBIT

With this set the second bit of the output register is set just before counting starts and is lifted just after counting starts. This can be used to coordinate with some external device which is also counting data. The same "TTL pulse" occurs at the end of counting as well.

COUNT :

/TIME

Tells the computer that you are counting for a length of time. This is recorded in the data file. Alternatives are DOSE and ROCK. TIME mode expects the pulses into the realtimeclock to come from the 262khz clock in the RTC module. The user must change the input A of the RTC. In this mode, TIME is in seconds, e.g. TI=2 will mean count for 2 seconds. This mode change is recorded both to SUPER.LOG and in each data file.

CROSSHAIRS

This is a synonym for CURSOR

CT

This is a synonym for COUNT

CTRL_C

^C (control C). This will stop all motors from moving. It will also abort a count if typed during a scan, without loss of data. Note that while the 4 diffractometer motors have ramp-downs on abort, the mono and table do not, so you are likely to lose steps if you abort a mono move. In general it is better not to abort a move if possible.

CTRL_Z

^Z (control Z) is used to get back to the SUP> prompt if the program takes you somewhere you don't want to go. For instance, if you type in the wrong scan numbers and don't want to perform the scan, when the program asks for a file name type ^Z to get back to the prompt. You can also abort scan with a ^Z at the comment line, although an empty file will be written to disk.

CURSOR

Used after plotting a scan to determine the position of a peak for instance. Cursor works differently for Xwindows, VT125 and TK4100 modes.

CURSOR :

VT125

Use the arrow keys to move the crosshairs horizontally and vertically. By entering a number from the keypad one can change the step size that a single arrow key makes. 0 moves the crosshairs the least, 9 moves them the most. The current position of the crosshair is listed in the third row of the non-scrolling region on the right hand side.

CURSOR :

XWINDOWS

The mouse is used to position the cursor in the Xwindow, clicking on the left-hand button on the mouse will report the position in the decterm window. To finish, click on the right-hand button of the mouse.

CURSOR :

TK4100

The mouse is used to position the cursor in the TK4100 screen. To turn off, click in the VT220 screen and hit several carriage returns. This doesn't work as cleanly as I would like.

Data

The data from the hexscalers is written to disk as integer values. In the case of a very large count (larger than 2e9 counts) the value is recorded as a negative value which is multiplied by 1.e-6. that is, 1e10 would be written as -1e4 on the screen and in the data file. The plotting will interpret a negative value properly for a signal channel (and not as part of a meta-channel).

DARK

To set the dark current (offsets) for ion chambers, use COUNT/DARK.

DEFINE

One can create up to 24 aliases within SUPER. These can be used either to emulate other programs (SPEC, other versions of SUPER) or to concatenate commands. The latter is done by delimiting commands with the "+" key. So DEF BR BRAGG+COUNT will execute first the BRAGG move, then the COUNT command. Variables passed in the BR command are parsed by the first of the actual commands, so BR 1 0 0 will move to h,k,l of 1 0 0 and then count. When executing aliases the verb must exactly match the definition. Verbs limited to 8 letters, equivalences limited to 40 letters.

DEFINE :

Examples

Many people have found the following to be useful: DEF FLOOP DIPS/PR+FIT/AUT DEF PR DIS/PR+DIS/NOPL

DEFINE :

Undefining

To turn off an alias, use UNDEFINE, as in UNDEFINE BR.

DEFINE :

Current_definitions

SHOW ALIAS will show the current list of aliases

DELAY

Pauses the program for a certain number of seconds. This is primarily useful in INDIRECT command files, where one would like to pause between the execution of a command or set of commands. There is only one parameter, the number of seconds to wait. The maximum number of seconds is ~84000, the number in 24 hrs.

DISPLAY

Plot a previously collected scan on the screen. Program defaults to the most recently collected scan. Can plot up to 16k pts. To see the current plotting choices, type DISPLAY/NOPLOT. Some are logical switches and affect all files until turned off, others only affect the one file. Check each to see. Note that you can change the logical switches and not plot a new file by combining several qualifiers with the /NOPLOT qualifier, i.e. DIS/CHAN=2/RAT=3/NOTRAN/NOPLOT. See Parameters for more detail.

DISPLAY :

Parameters

The only parameter is a file name. The program defaults to the most recently collected file. For scans with the same file name but a different extension type ".123" rather than "file.123". By including directory specifications other files can be plotted. A "File not found" either means what it says or that you have insufficient privilege to read the file for plotting. If you would like to look at a set of old files (say, during a time while the machine is filling) you can change the default file name with the FILE FRED.100 command. Then you can look at all the FRED files by just typing the extension, e.g. .123. After you are done looking at old files return the default file to the right name (FILE MORTIMER.187) and the next scan will prompt you for the right default. If you would like to look at the last file of another series type the name without dot or extension and it will be plotted. Note that this doesn't change the default file name. The asterisk "*" is interpreted to mean the current default file.

DISPLAY :

Qualifiers

DISPLAY :

/ADD

Defines a second channel which will be added to the channel defined by /CHANNEL. The sum of the two channels is plotted. Turn off with /NOADD.

DISPLAY :

/ASCII

Writes a file of x,y pairs separated by commas. Concatenates the file name and adds .csv as the new extension. If there is a ratio channel, the output is multiplied by the average value of the monitor throughout the scan. If there isn't a ratio channel, you get the signal directly.

DISPLAY :

/BIN

Create output file of x,y values in binary (bien) format. This is not a logical switch, it only effects the current scan.

DISPLAY :

/CHANNEL

Is used to choose which channel is plotted as Y. Channels are from 1-6, not 0-5 as is listed on some hexscalers. Note, the program can deal with up to 7 hex scalers, 42 channels, so reference to chan 1-6 is merely illustrative for the first hexscaler. Syntax: DIS/CHA=3 will plot channel 3 from now on. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/DEFAULT

Resets the plotting values as: channel=1, no ratioed channel, no transmission channel, no add channel, line plots, linear scale, no fixed limits, plot full x-range, Integer scans plotted with largest delta as x-range.

DISPLAY :

/DERIVATIVE

Plots the derivative of the scan, using the current settings for /CHANNEL,/RAT,/TRAN, etc. Note that if LOGPLOT is set, you will get the log of the derivative, too. Note that the code takes a 15 point 1st derivative and a 17 point second derivative, so the scans need to be significantly longer than that to work. 50 seems like a good minimum.

DISPLAY :

/DIVIDE

This plots the ratio of the previous data set divided by this data set. A way of looking at the ratio between two scans, rather than the ratio of two channels within a scan. The two files must have the same number of data points. For looking at the ratio between two channels of a single file, use /RATIO.

DISPLAY :

/EXAFSPAK

This has been implemented as ADDFIL/EXAFSPAK, where a SUPER data file can be output in the binary file format readable by EXAFSPAK. For technical reasons, it was easier to put it as a qualifier for ADDFIL than to put it here in DISPLAY. Note that you can simultaneously sum spectra and output them in EXAFSPAK format.

DISPLAY :

/GSAS

Generate a datafile in a format acceptable to GSAS, the LANL Rietveld analysis package. The output file is the input file with an extension of .HIS, e.g. test.032=>test032.his. If you normalize the data (with RAT=n) the GSAS version will multiply the data by the average of the ratioed channel, so that the result will give reasonable esd's.

DISPLAY :

/HEADER

Types all the header lines of the file to the screen, without plotting the data. Useful for seeing the initial motor positions.

DISPLAY :

/ID

For integer scans, plots the largest of deltaH, deltaK or deltaL as the x-axis. This is the default integer plotting mode. It is a logical switch with the other choices (IH,IK,IL,IM).

DISPLAY :

/IH

For integer scans, plots deltaH as the x-axis. It is a logical switch with the other choices (ID,IK,IL,IM).

DISPLAY :

/IK

For integer scans, plots deltaK as the x-axis. It is a logical switch with the other choices (ID,IH,IL,IM).

DISPLAY :

/IL

For integer scans, plots deltaL as the x-axis. It is a logical switch with the other choices (ID,IH,IK,IM).

DISPLAY :

/IM

For integer scans, plots the magnitude of the vector in inverse angstroms as the x-axis. It is a logical switch with the other choices (ID,IH,IK,IL).

DISPLAY :

/LINE

Plots a line through the data points. The alternative is points enabled by /POINT. This is a logical switch setting, so it will remain in force until DIS/LINE is entered. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/LOGPLOT

Plots the y values as log10(y). This is a logical switch, so all successive plots will be plotted as log10(y) until the negated command "/NOLOG" is typed. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/NOPLOT

By including NOPLOT one can change plotting parameters without having to actually plot a file. This will also type the logical switch settings on the screen. If the ratioed channel=0, it means NORAT is in effect. If the Tran chan= 0, then NOTRAN is in effect. If an INDIRECT command file is being run, DISP/NOPLOT will change settings without listing them, so you can do an intricate set of overlays and return the settings to their original condition at the end. NOPLOT is also used to terminate a set of plots to be printed (with the DISPLAY/PRINT option).

DISPLAY :

/OVERLAY

Overlays a second plot on top of the first one, using the limits of the first plot. This is not a logical switch, it only effects the current scan.

DISPLAY :

/POINT

Plots the data as individual points. The alternative is enabled by /LINE. This is a logical switch setting, so it will remain in force until DIS/LINE is entered. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/PRINT

DISPLAY/PRINT has been replaced by PRINT. See HELP PRINT.

DISPLAY :

/RATIO

Plots the ratio of two channels. DIS/RAT=3 will plot (chanI/chan3). ChanI is changed using the /CHAN switch. To turn off ratio, type DIS/NORAT. Note that channel numbers are from 1-6 rather than 0-5, as is sometimes shown on the hexscaler. To look at the ratio between 2 files, use /DIVIDE. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/RESCALE

Overlays a plot on the current plot, rescaling the y values to fit the plot on the screen. This is not a logical switch, it only effects the current scan.

DISPLAY :

/SECOND

For A0 scans and SIMULTANEOUS (S) scans, plots the second motor as the x-axis rather than the first motor. As LINEUP/RADIAL looks like an S scan on disk, works for that scan as well.

DISPLAY :

/SUBTRACT

This will subtract the data from a file from the data of the previous file. This is not a logical switch. The number of points must be the same for both files. This only effects the plotted data, not the data file itself. Will work in conjunction with /ratio, etc.

DISPLAY :

/SUPPRESS

This has been superceded by /YMIN, as YMIN allows both 0. and other values. See /YMIN for details.

DISPLAY :

/SWITCH

This is the same as NOPLOT. It shows the current plotting switches without plotting a file.

DISPLAY :

/TK4100

One of the three display modes for plotting scans. The others are

DISPLAY :

/VT125 and /XWINDOWS. SCAN/UPDATE only works in /XWINDOWS mode.

DISPLAY :

/TRAN

Plots the natural log of the channel defined by /CHANNEL divided by the channel defined in /TRAN. This is useful for transmission EXAFS data. Syntax: DIS/TRAN=3 will plot the data as ln(chan3/chanI). ChanI can be changed by the /CHAN switch. If you would like to see ln(1/chanI) set the /CHAN channel equal to the /TRAN channel. To change back to regular plotting style, type DIS/NOTRAN. Note that channel numbers are from 1-6 rather than 0-5, as is sometimes shown on the hexscaler. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/TYPE

List the x,y values on the screen rather than plotting. This is not a logical switch, it only effects the current scan. If you want a hard copy of a listing, you can type CTRL-F2 and the vt240 will run in "print-along" mode, printing everything that is typed on the screen. Typing CTRL-F2 again will turn off print-along mode.

DISPLAY :

/UPDATE

To turn on or off automatic scan updating. This is the same command as SCAN/UPDATE or SCAN/NOUPDATE.

DISPLAY :

/VT125

Sets the display mode to be the terminal screen and uses REGIS graphics. This is the default mode, but you can't use SCAN/UPDATE in this mode. See DIS/XWINDOW to use SCAN/UPDATE. Another choice is /TK4100

DISPLAY :

/WRITE

Create output file of the x,y values in x,y ASCII format This is not a logical switch, it only effects the current scan. The first line is the number of points in the scan.

DISPLAY :

/XCHAN

This will plot one of the Y-channels as the X-array variable. One cannot take the ratio, or modify that channel in any way. It might be useful to plot signal vs. LVDT signal, or some such. Tom R. asked for it. Turn on with /XCHAN=n, Turn off with /NOXCHAN.

DISPLAY :

/XFULL

This is a logical switch between plotting the full x-range and plotting only the x-range collected so far. Useful for seeing narrow peaks that occur in the data early in the collection range. Turn off with /NOXFULL

DISPLAY :

/XLOG

This is a logical switch for changing between plotting the x-values linearly and log-based 10. Turn off with /NOXLOG.

DISPLAY :

/XMIN

Defines a minimum x-value for plotting which is constant from scan to scan. This is a logical switch which is turned off with /NOXMIN. Usage: DISPLAY/XMIN=2.5 To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/XMAX

Defines a maximum x-value for plotting which is constant from scan to scan. This is a logical switch which is turned off with /NOXMAX. Usage: DISPLAY/XMAX=40. To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/XWINDOW

If you are running from an X-terminal (and not set host 0), then you can plot your data in an X-window. Super uses the pgplot library for its xwindow plotting, so there is a separate icon which pops up on the screen, followed by the x-window. If DIS/XWIN is turned on, then you can get real-time plotting of your scan by turning on SCAN/UPDATE. The other choices for plotting are /VT125 and /TK4100. SCAN/UPDATE only works in /XWIN mode. It requires that the DECW$DISPLAY logical be defined, so if you set host 0 from a terminal, your new session won't have that automatically defined.

DISPLAY :

/YMIN

Defines a minimum Y-value for plotting which is constant from scan to scan. This is a logical switch which is turned off with /NOYMIN. Usage: DISPLAY/YMIN=2.5 SETTING YMIN=0 IS THE SAME AS THE OLD NOSUPPRESS QUALIFIER To determine the present logical switch settings, type DISPLAY/NOPLOT

DISPLAY :

/YMAX

Defines a maximum y-value for plotting which is constant from scan to scan. This is a logical switch which is turned off with /NOYMAX. Usage: DISPLAY/YMAX=1000. To determine the present logical switch settings, type DISPLAY/NOPLOT

EDIT

Edit a file using the EDT editor. Defaults to sys$login: for the directory and '.ind' for the extension. The editor used here, in NOTE/EDIT and IND/EDIT is EDT. The commands for exiting from the editor are: ^Z (Control-Z) gets you to the command prompt, which is a '*' at the bottom of the page. Typing 'exit' will write the contents of the buffer to the file. Typing 'quit' exits the editor without saving anything. EDT uses the keypad to select words and move around the screen. To learn how to use the EDT editor, check the VMS manuals. One can get by in EDT using the cursor keys; Once in EDT, typing the PF2 key will show the numeric keypad and its functions.

EXAFS

For the EXAFS user, you may want to modify SUPER to make it more friendly to your kind of experiment. First, you should turn off the diffractometer calculation mode, by typing MODE/NODIFF. This removes the HKL from the top of the screen. You may want to remove extraneous motors, using the ASSIGN command. Typically, you would have MONO, TABLE, HORZ and VERT (sample positioner motors) as the only motors in the system. For most users, 2 significant digits are sufficient for these motors.

EXAFS :

a_EXAFS

To move a motor without scanning, use the MOVE command. For scanning, typically, you will use 3 kinds of scans. M-scans, for moving individual motors to align them, E-scans (up to 3 regions with different delta-energy steps for each region) and X-scans (2 regions of constant delta-e, and one region of constant delta-k). For more info about these scans, see HELP SETUP ENERGY, HELP SETUP XSCAN, and HELP SETUP MOTOR. To check the count rate, type COUNT. To change the count time, either use COUNT or TIME. You can change the name of your data files using FILE. The header line of each data file includes the name of the file, the date and time, a SAMPLE name and comment. The SAMPLE name is for those things that don't change from scan to scan, whereas the comment is for those things that do.

EXAFS :

b_EXAFS

For scattering experiments, the second channel of the hex-scaler is typically a constant frequency input and is used as a clock. You may prefer to turn that feature off by typing COUNT/NOSCATTER, which reports the second channel as counts rather than as time. COUNT/CHANNEL sets the number of hex-scaler channels recorded to disk. You should also be sure that you are in TIME mode by typing COUNT/TIME. The alternative is DOSE mode, which is only a choice on scattering beam lines. Most beam lines only have a single real-time-clock, so they are set up for time mode.

EXAFS :

c_EXAFS

To display the data, run SPLOT in a separate Decterm window. SPLOT and SUPER talk to each other, and share the same plot parameters. Use DISPLAY to see an old file (or change plot parameters). Use UPDATE to see the current file. See DISPLAY/PRINT for how to print a hard copy of the curve. If you are running a transmission exafs experiment, you may want to look at the data as ln(I0/I). This can be done by (assuming I0 is in channel 3 and I is in channel 1) typing DISPLAY/CHAN=1/TRAN=3/NOPLOT. From then on, each time you plot data (either with UPDATE or with DISPLAY) the data will be plotted as ln(chan3/chan1). Warning!! Some hex scalers have channels listed from 0-5 rather than 1-6. These notes always refer to channels as if they were 1-6.

EXAFS :

d_EXAFS

One can determine the dark-current of the keithleys using the COUNT/DARK command. These results will be written as part of the header of each data file. COUNT/(NO)OFFSET will change whether the data written to disk has these offsets already subtracted or not. Most exafs users scan the same sample multiple times and want to see what the averaged data looks like. This can be done using the ADDFIL command. The resulting file will have the name of the first file in the series with an 'S' appended to the extention and the header of the last file in the series.

EXIT

Exits the program, writing variables to SUPER.PARAMETERS and recording current positions to SUPER.LOG. END and QUIT also work.

FILENAME

Changes the name used for the data files without having to run a scan. This is useful when changing samples so one doesn't forget to change the name as well. This way lineup scans can be run as the first scans for a new sample and have the proper name. If the file name is entered without an extension AND NO DOT and there are no files in the directory by that name the extension '.001' is chosen. If files already exist with that name, the filename with the highest numerical extension is chosen. Syntax FILE NEW_NAME.108 sets the default file to new_name.108. FILE NEW_NAME does a DIR and finds the latest version of NEW_NAME and chooses that. FILE NEW_NAME. (with a dot on the end) will result in the new file name being NEW_NAME.001. Note that FILE works in SPLOT as well, but it changes the name of the file for scanning as well, so use the command wisely.

FIT

Will fit a spectrum with up to 4 peaks and a linear background. Choices of peak shape include pure lorentzian, pure gaussian, or a sum of gaussian and lorentzian. There is also a fit to a linear background. What is printed out is the slope of the line and the value of the line at the peak position, i.e. y(xpos). One can also chose a constant peak width for multiple peak fits. Results are printed on the screen and optionally written to the log file. FIT must follow DISPLAY or UPDATE. FIT NOW IS THE SAME AS FIT/AUTO, i.e. IT ATTEMPTS TO FIT ONE PEAK. To fit up to 4 peaks, use FIT/NOAUTO.

FIT :

Qualifiers

FIT :

/AUTO

Will attempt to fit a peak, including linear background, without prompting for any parameters. Peak shape defined by /FUNCTION switch. THIS IS THE SAME AS FIT

FIT :

/NOAUTO

Will allow a fit of up to 4 peaks.

FIT :

/FUNCTION

Sets the curve shape for the auto fitting procedure. Choices are 0=Gauss, 1=Lorentz, 2= Voigt. Syntax requires an equal sign, e.g. FIT/FUN=2.

FIT :

/REFIT

Allows you to fix some of the previously fit variables and refit the remainder. There are 4 variables per peak, so an example of refitting would be to fit 3 peaks with pure gaussians, then on refit you would enter 1,2,3,5,6,7,9,10,11 to hold fixed the position,height and width and just allow the fraction Lorentzian to vary.

FOLLOW

Follow is used to tell the computer to monitor the positions of the motors continuously and update the screen with their positions. This is useful when performing a manual move of the motors using the toggle switch on the Stepper Motor Controller in the CAMAC Crate. I would suggest you use TWEAK instead.

Food

Pastrami/Swiss sandwiches and Anchor Steam at the Dutch Goose(854-3245) Su Hong(togo)(322-4631) esp. General's chicken, Dry-brazed beans, KunPao prawns; Ramona's(326-2220)(R'sToo=322-2181) or Applewood 324-3486 for Pizza, although Tony and Alba's(968-5089) is the best (albeit further). If really in hurry, Round Table(854-1140) on the Alameda across from the Goose. Luttikens(854-0291) for good big sandwiches (on the Alameda past the Goose). Mextogo (321-9669) good burritos. Casa Isabel on Park near California for sit-down Mexican. Marco Pollo (across from the Goose) for chicken&ribs to go(854-8244).

General_Hints

These are selected topics which you might want further info about.

General_Hints :

Home_directory

Each user is given two directories. The files which you would like to keep permanently between runs should be kept in your login directory. This is typically $USER:[B_YOUR_NAME] and is referenced as SYS$LOGIN:. SUPER.PARAMETERS, which contains the 20 scans in SETUP and options such as scan mode, plotting mode etc. is stored there and files used in SCAN/FILE and INDIRECT commands which you would like to save for the next run should be transfered from $DATA:[B_YOUR_NAME]: to SYS$LOGIN:. Note that there is limited permanent storage allowed in SYS$LOGIN: so be judicious about what is saved between runs.

General_Hints :

Data_directory

Each user is given two directories. One is on $USER: and the other is on $DATA:. All data files are written into $DATA: with the user's directory name. This has been assigned the logical name $SUPER_DATA:, so if you want to see what files are in that directory, typing $ DIR $SUPER_DATA: will show you a list of the files. SUPER.PARAMETERS is stored on $USER:[B_YOUR_NAME], which has the logical name SYS$LOGIN:. Files you would like to preserve between runs can be stored here. This account has only a small storage allocation so data can't be stored there. Data in $SUPER_DATA: is not saved after you leave. Be sure you backup your data before you leave. (See BACKUP).

General_Hints :

Default_directory

When you first log on the default directory is SYS$LOGIN:. To change between directories use the command $SET DEFAULT new_directory. All data files go into $SUPER_DATA: (which is $DATA:[B_YOUR_NAME]) as does SUPER.LOG. SUPER expects to find .IND files and SCAN/FILE files on $SUPER_DATA:, so most of the time you will want to have $SUPER_DATA: as your default directory. When prompted for an IND or SCAN/FILE file name you can include the directory if the file is not in $SUPER_DATA:. Note that one can add a LOGIN.COM account which is executed on logging in. commands such as SET DEFAULT can be placed there so one is automatically in the proper directory.

General_Hints :

Current

The SPEAR current is available on a database on SSRL. This has been implemented into the program by recording the current on the line preceding the header line of a scan in the SUPER.LOG file. There are times, however, when either the SPEAR computer or SSRL is down in which case the current is recorded would be the last updated value. If you suspect that has happened try exiting the program and re-entering it, as the initialization of this feature only occurs at program startup. If SUPER seems to hang during startup, it may be that the node where SUPER gets its information is down. If it is likely to be down for a while, you may want to turn off current reporting. You can do that by $deassign/sys/exec sibyl_node

General_Hints :

1Backup

One can (and should) back up data regularly. The most convenient way is to back up to SSRL. You should have an account on that machine as well. To back up your files, first log onto SSRL and $ CREATE/DIR $TEMP1:[B_YOURNAME] creates a directory on a temporary disk $temp1:. Then create a series of subdirectories, e.g. $ CREATE/DIR $TEMP1:[B_YOURNAME.BACK01] $ CREATE/DIR $TEMP1:[B_YOURNAME.BACK02] etc. Now log off, and

General_Hints :

2Backup

$ COPY $SUPER_DATA:*.*;* SSRL::$TEMP1:[B_YOURNAME.BACK01]*/LOG Record the date and time you did it. Next time you back up, $ COPY/SINCE=01-APR-1992:19:30 $SUPER_DATA:*.*;* SSRL::$TEMP1- _$ :[B_YOURNAME.BACK02]*/LOG And each subsequent time you back up, do a copy/since=date etc. If all goes well, At the end of the run you will still have all your data on the beam line machine and you can create one last directory [.backfinal] on SSRL and do a complete backup of all the files to it. Then use FTP to send the files from SSRL to your host machine. You may want to send copies of the interim directories to your host machine as well. FTP is quite fast.

Hardware

These are a list of topics concerning the electronics used by the system

Hardware :

Stepper_motors

The stepper motors are run using Joerger SMC 24-A controllers or E500 stepper motor controllers. VAXMOTORS is an underlaying program which figures out what commands work for each controller and motor.All calls to motors within SUPER are through VAXMOTORS. Type HELP VAXMOTORS from DCL level (ie from outside the program) to get more info. The 24-A controllers have a soft abort feature so that typing Ctrl/C causes the motor speed to ramp down slowly and then stop.

Hardware :

Ion_Chambers

Occasionally one will need to use ion chambers rather than photo-tubes for data collection. There is a separate Fluke high voltage power supply in the rack for that purpose. The ion chamber output is amplified and turned into a voltage by a Kiethley current amplifier, then fed to a Voltage to frequency (V-F) converter in the NimBin above the CAMAC crate. The Kiethley output voltage is also displayed on the DVMs above the NimBin. The output of the V-F is then put into the hex counter (typically in slot 9 of the camac crate). The ion chamber high voltage is typically run at -300 V.

Hardware :

Photomultipliers

Generally data is collected using photomultiplier tubes. Their voltage is typically 700 V or so. As of 4/90 the 7-2 tubes were negative HV.

Hardware :

Solid_State_Detectors

For Anomalous scattering experiments an intrinsic Ge detector is often used. This detector needs a special HV power supply which has a remote shutdown option to protect the detector in case it warms up. The high voltage is typically -1500 V, but is listed on the detector, so check! It uses a spectroscopy amplifier, unipolar output, gain 500+10.5 at ~7000 eV, 6microsec shaping time. This signal can be put into the SCA module for selecting the right window. To help in setting windows a delay amplifier and a linear gate are needed. The output of the spectroscopy amp is teed into the SCA and the delay amp set to 3microsec. The output of the delay amp is put into the linear gate, and the output of the linear gate goes to the MCA. The enable of the gate is taken from the SCA window of interest. Thus only pulses with the right energy are sent to the MCA to be processed.

Hardware :

Device_Off_Line

Occasionaly one of the camac modules may be put "Off line". This will typically be accompanied by an error message: SYSTEM-F-DEVOFFLINE, device is not in configuration or not available this will occur if the module has been generating too many LAMs. To fix the problem, figure out which slot the device is in, and from outside the program type: $ CAMAC/RESET CMAn: where n is the camac slot number. Motor controllers, Hex scalers, real time clocks and QOR modules are all capable of generating LAM's. If a $CAMAC/SHOW CMAn: results in a "Yellow LAM limit set", then that device needs to be reset. (fix the problem first BTW).

Hardware :

Real_time_Clock

The real time clock (RTC) is used to inhibit pulses into the hex scalers when the program doesn't want them. When the program wants pulses coming to the hex scaler to be counted it loads a value into the register. While this value is non-zero the inhibit to the hexscaler is lifted. There are two modes for collecting data. In the most often used mode (DOSE) the hexscaler counts pulses for a certain number of I0 pulses. The scans include as their last value the number of pulses to collect. The alternative mode is to use a clock generator (the Joerger clock generator with several lemo connectors on it) which sends out pulses at timed intervals. This is TIME mode. The pulses either from the I0 detector or the clock generator are put into the INPUT A of the RTC. The value loaded into the register at the start of a count cycle is decremented until zero is reached. Typical I0 counting rates are 10k/sec, so the 10cps channel from the Joerger is a good choice for TIME mode. See COUNT for more info.

Hardware :

Calc_assumptions

For efficiency sake the subroutines performing the angle calculations between real and reciprocal space make certain assumptions about the motors. For the 4-circle calculations it assumes 2theta=motor 1, theta= motor 2, chi= motor 3 and phi= motor 4. In Psi mode, Psi= motor 5. For Z-axis calculations it assumes motors 1-5 are 2theta, theta, alpha, beta and stage, where stage is the translation of the beta rotary table. It also assumes alpha is fixed by the experimenter and sets beta to achieve the correct l value.

HELP

Lists these commands. To print out a hard copy of this file, type (from outside the program) $ print/queue=s07_ln03p ssrl$local:[super]super.hlp Note, if you are in bldg 131 you might prefer one of the printers in that building.

HISTORY

Use RECALL instead.

HVAL

This command treats a motion in the h-direction in reciprocal space as if it were a motor. One can type HVAL 2.3 to move to 2.3 in the h-direction, leaving k and l fixed. HVAL/REL .1 will move relative that amount. SEE KVAL AND LVAL.

INDIRECT

Executes an indirect command file. Most commands can be executed in this manner except for FOLLOW, etc. The default directory for the file to be executed is your login directory, (SYS$LOGIN:) The default extension is .IND. Syntax: IND SILICON.IND Up to 500 commands can be executed within a single ind command file. This is not a real limitation, as the last command can be to open the next .IND file. NOTE: This works in SPLOT as well as SUPER. Recursion is now possible, although the 500 line limit still holds. A variable can be passed into the ind file with @ (see /EDIT).

INDIRECT :

Qualifiers

INDIRECT :

/EDIT

Will put you into a full screen editor to create an IND file. Uses the EDT editor. (SEE Editor). One can pass a variable into the IND file by using the @ symbol. Thus, an ind file TEST.IND that says COUNT @ can have a different count time, e.g IND TEST 3 will result in a count for 3 seconds.

INDIRECT :

/TEST

This will check the grammar of an IND file to make sure there are no typos. Will NOT check whether a scan will hit limits.

INVERSECAL

Calculate h,k,l values given 2theta, theta, phi and chi values. If values are not entered will prompt, using the current values as defaults. Syntax: INVERSECAL 20,10,.1,.1

KVAL

This command treats a motion in the k-direction in reciprocal space as if it were a motor. One can type KVAL 2.3 to move to 2.3 in the k-direction, leaving h and l fixed. KVAL/REL .1 will move relative that amount. SEE HVAL AND LVAL.

LIMIT

Lists the upper and lower limits of all the motors. To change a limit, use the switch /HIGHLIMIT or /LOWLIMIT on a motor, e.g. THETA/LOWLIMIT 2. If you have (shame on you!!!) run into a hardware limit, you first have to move off the limit condition using the toggle switch on the Joerger SMC. Once the limit condition has been turned off you need to reset the hardware limit condition with, e.g. THETA/CLEAR to clear the hardware limit on the THETA motor.

LINEUP

Lineup scans quick scans for finding maximum signal by varying a single motor about the present position with all the other motors at their present positions. Parameters are motor name, step size, and number of steps on one side of present position that you want to start. Will scan 2n+1 times that number of steps. If time is specified as last parameter, uses it and accepts that as the new default time, otherwise assumes time value as specified by TIME parameter. Auto-increments file name and sample header. Syntax: LINE PHI,.02,10 will move PHI .2 degrees below its present position, and scan through to .2 degrees above the present position. Returns to the present position when done. The file format for an LINE scan is identical to an M(n) scan, so LINE PHI... looks on file like an M4 scan with the correct initial motor positions.

LINEUP :

RADIAL

One can do a radial lineup scan (moving both THETA and 2THETA) by telling LINEUP to move the RADIAL motor. You should enter the 2THETA delta angle and the program will move THETA by half that amount. The disk file looks like a simultaneous (S) scan.

LINEUP :

HVAL

One can scan in reciprocal space, making a pure h-direction scan, by LINE HVAL

LINEUP :

KVAL

One can scan in reciprocal space, making a pure k-direction scan, by LINE KVAL

LINEUP :

LVAL

One can scan in reciprocal space, making a pure l-direction scan, by LINE LVAL

LINEUP :

Qualifiers

LINEUP :

/CENTER

Logical switch between returning to starting position after the scan or returning to the centroid as calculated within the scan. The centroid is reported at the end of the scan. Turn off with /NOCENTER.

LINEUP :

/RETURN

This will return motors to their starting position if the previous command was a LINEUP command. Useful if you ctrlC out of a scan and want to get back to the starting point. This is not a logical switch

LINEUP :

/ROCK

Logical switch which if set writes the scan header as an R scan rather than an M scan. This only occurs for the diffractometer motors, not for the others (e.g. TABLE). Useful for recording HKL where the scan was performed instead of merely the single motor value. Turn off with /NOROCK.

Log_file

The program writes a log file on $SUPER_DATA:SUPER.LOG which records important events that occur in the program. Whenever a motor position is changed using /RESET the old and new values are recorded in the log file along with a time stamp. The header line and scan parameter line from each scan is logged. The SPEAR current is read from a database on SSRL and recorded just prior to the header line of each scan. Any changes to the orientation matrix are logged. You can also write comments to the log file (see NOTE). I have found this log file to be extremely useful in "playing back" a run afterwords. Each day the program is run the previous SUPER.LOG is renamed to be the creation date of that log file followed by .LOG. That is, on January 7, if SUPER is run, the log file from January 6 will be renamed 6_JAN_1992.LOG and a new SUPER.LOG will be created.

LUP

This is a synonym for LINEUP

LVAL

This command treats a motion in the L-direction in reciprocal space as if it were a motor. One can type LVAL 2.3 to move to 2.3 in the l-direction, leaving h and k fixed. LVAL/REL .1 will move relative that amount. SEE HVAL AND KVAL.

MODE

Changes calculation mode. A 4circle diffractometer has a variety of calculation modes because there is one extra degree of freedom in positioning the sample. Generally /Omega mode is used, which limits the theta axis to be 1/2 of 2theta. Alternatives are 2circle mode and phi mode. Also possible is Zaxis mode and Psi mode, for a rotation about a reciprocal lattice vector.

MODE :

Qualifiers

MODE :

/OMEGA

Omega=0 mode choses theta to be 1/2 of 2theta and uses phi to equal omega.

MODE :

/PHI

Phi=0 mode, sets theta=1/2(2theta)+ omega

MODE :

/2CIRCLE

Only considers the positions of 2theta and theta. As a result, only can calculate h,k,0 type reflections, and if you enter a non-0 l-value will calculate the zeroed version of it. Has a predefined orientation matrix with (1 0 0) at 0,0,0 and (0 1 0) at 90,0,0.

MODE :

/POWDER

Only considers the positions of 2theta and theta, but assumes the sample is a powder, so has no orientation matrix and calculates the 2theta value from all 3 of h,k,l, and sets theta to be 2theta/2. Thus one can BRAGG to a (2 2 1) reflection or calculate the 2theta position for a (3 3 3) reflection, but only 2theta and theta move. Note that what is reported at the top of the page is Q [A^-1], not h or k or l (or all 3), even though the ca and br commands are in reciprocal lattice units, not A^-1.

MODE :

/ZAXIS

For z-axis spectrometers consisting of incident angle(alpha), theta, 2theta and detector take-off angle(beta). If beta is an offset rotation it must be specified (MOVE/OFFSET_ROTATION). The distance of the translation table from the theta axis is a variable (See PARA/STAGE). In this geometry the alpha value is assumed fixed, and beta is set by the program to achieve the correct l value.

MODE :

/ZAXNOBETA

In some cases only 2theta, theta and alpha are present. In those cases an imaginary beta axis is assumed which is equal to alpha. In this case alpha is moved by the program such that alpha and the imaginary beta combined achieve the correct l value.

MODE :

/PSI

Calculates a rotation angle about a reciprocal lattice vector (RLV) depending on a reference RLV. It assumes the current RLV is the vector about which the rotation should occur. It will prompt you for the reference RLV (the direction Psi=0) which defaults to the current RLV with theta= theta+90. In Psi mode one can change the RLV that the Psi rotation refers to on the fly, but the reference RLV (the direction Psi=0) can only be changed explicitly, by typing MODE/PSI again and entering a new reference RLV. Note that the reference RLV doesn't have to be orthogonal to the rotation RLV, but it cannot be parallel.

MODE :

/NODIFF

This mode doesn't display the h,k,l values at the top of the screen nor does it do calculations for you. One can still move motors and do motor and angle scans, but integer scans don't work.

MODE :

/ALPHA

Calculates how to get to a reciprocal lattice vector based on keeping the angle of incidence on the crystal surface at a fixed value. This mode prompts you for a specific value of alpha. It works in concert with PSI mode, and the PSI motor is inserted into the motor list. Typical PSI values will be -90+/-1 degrees. The program prompts for the values of CHI and PHI which correspond to the surface normal aligned with the THETA axis. These are stored on disk and remembered.

MODE :

/BETA

Calculates how to get to a reciprocal lattice vector based on keeping the take-off angle from the crystal surface at a fixed value. This mode prompts you for a specific value of beta. It works in concert with PSI mode, and the PSI motor is inserted into the motor list. Typical PSI values will be -90+/-1 degrees. The program prompts for the values of CHI and PHI which correspond to the surface normal aligned with the THETA axis. These are stored on disk and remembered.

MODE :

/PWCHI90

Calculates how to get to a reciprocal lattice vector with Chi= 90. and Omega added to Theta. This is the "second setting" of Busing and Levy.

MODE :

/NWCHI90

Calculates how to get to a reciprocal lattice vector with Chi= 90. and Omega subtracted from Theta. This is the "first setting" of Busing and Levy.

MODE :

/ALEQBE

This mode fixes PSI equal to -90 degrees.

MODE :

/NOCELL

This mode forces a0,b0 and c0 to 2*pi and only reports Q, not h,k,l. If working with an amorphous material, this is the best "calculation" mode. Note that this also changes the orientation matrix, so don't go into this mode unless you have written down your old values.

MODE :

/OMFIXED

Fix omega to be a specific value. This is a generalization of the Omega= 0. mode.

MODE :

/PHFIXED

Fix Phi to be a specific value. This is a generalization of the Phi=0. mode.

MODE :

/THFIXED

Fix the theta axis to be a specific value. This is a variation of the OMFIXED switch, but in this case the physical axis doesn't move, whereas with OMFIXED THETA changes when 2THETA does.

MOVE

This is the command for moving a motor. The MOVE verb is not actually necessary, but is available as an option. One can either type MOVE 2THETA 10. or 2THETA 10. and the 2THETA motor will be moved to the absolute position of 10 Deg. If a motor name is typed without the MOVE or the position, the current position will be typed on the screen. Any of the motors listed across the top of the screen can be moved using this command. Three letters are sufficient to distinguish between various motors. There are a number of qualifiers, all of which change the database of the motor, such as changing its position or its limits.

MOVE :

Special Names

There are 4 special names for "pseudomotors". These are RADIAL, HVAL, KVAL and LVAL. For the RADIAL motor, you enter the 2THETA value, and the program moves the THETA motor 1/2 that value. For the HVAL motor, you give the h of h,k,l and it will move all four (for 4-circle modes) motors to change h to the new value. the k and l values are unchanged. For the KVAL motor, you give the k of h,k,l and it will move all four (for 4-circle modes) motors to change k to the new value. the h and l values are unchanged. For the LVAL motor, you give the l of h,k,l and it will move all four (for 4-circle modes) motors to change l to the new value. the h and k values are unchanged.

MOVE :

Qualifiers

MOVE :

/BACKLASH

Backlash defines the number of additional steps taken by the motor so that moves always end up going one direction. The value is scaled, not steps. The sign of the backlash is such that of the move removing the backlash, thus a positive backlash is employed on negative moves. The syntax is 2THETA/BACKLASH 0.1

MOVE :

/CIRCLE

Tells the computer that this is a circular motor, i.e. that 340= -20. This allows motors to take the shortest direction from one position to another. This is incompatible with having limits on the motor.

MOVE :

/CLEAR

If a motor runs into a hardware limit it must be cleared before it can be moved again. Due to inertia you are likely to have lost your position, so the first rule is: Don't run into hardware limits. The syntax is 2THETA/CLEAR

MOVE :

/DISABLE_LIMITS

To turn off limits for a motor, you use this switch. To turn back on, use /ENABLE_LIMITS

MOVE :

/ENABLE_LIMITS

To turn on limits for a motor, use this switch. To turn off, use /DISABLE_LIMITS

MOVE :

/HIGHLIMIT

Highlimit defines the software high limit of the motor. The program can be set to test each position of a scan before the scan starts to see whether limits are surpassed. See SCAN/TEST The syntax is 2THETA/HIGHLIMIT 3.

MOVE :

/INFLECTION

Only valid for the Mono motor, will go to the zero crossing of the second derivative of the mono scan of the previous scan. The inflection point is only calculated during E or X scans, and is calculated looking at the signal going into the channel defined PARAMETER/I1EDGE, which defaults to the same channel as the OPTIMIZE/CHANNEL channel. One can have a normalized signal by defining PARAMETER/I0EDGE, at which point the ratio I1EDGE/I0EDGE is used to determine the inflection point. The zero crossing is also reported after a DISPLAY/DERIVATIVE command. To protect against a beam dump, a minimum number of counts is needed, the same number used in OPTIMIZE/MINIMUM. Note that the code takes a 15 point first derivative and a 17 point second derivative, so a minimum of 50 points is needed for a good scan.

MOVE :

/LOCK

Lock tells VAXMOTORS not to accept any move commands for a particular motor. If one needs a critical motor to not be moved by accident this command becomes useful. The syntax is 2THETA/LOCK

MOVE :

/LOG

If this switch is specified the next move will be recorded in SUPER.LOG. This will look similar to an optimize, e.g. it will have a date and time stamp, list the motor name and the old and new values of the motor. This is not a logical switch, but most be specified each time you want it.

MOVE :

/LOWLIMIT

Lowlimit defines the software lower limit of the motor. The program can be set to test each position of a scan before the scan starts to see whether limits are surpassed. See SCAN/TEST The syntax is 2THETA/LOWLIMIT 3.

MOVE :

/OFFSET_ROTATION

Defines an axis as the rotation of a 2-motor offset rotation. Assumes that the next motor in the list is the translation of the offset rotation. Turn off with /NOOFFSET_ROTATION.

MOVE :

/PARAMETERS

Lists the Backlash, Scale, Low and High limits for that motor.

MOVE :

/RADIANS

This will move a motor in relative radians rather than absolute position, ie 2THETA/RADIANS -.01 will move 2theta - .01 radians with respect to its present position.

MOVE :

/RELATIVE

Move the motor a relative numbe of degrees. MOVE/RELATIVE THETA .1 will move THETA .1 degree from its present position.

MOVE :

/RESET

Reset is used to take the current physical position of the motor and redefine it to be a new scaled value. The syntax is 2THETA/RESET 23.871 One can do a reset without moving to the position to be reset by giving that value as the second parameter. Thus if you wanted to reset theta from 19.5 to 19, but were actually at 23 degrees, you could type: THETA/RESET 19 19.5 and 23 would be reset to 22.5 degrees, that is, the current position is reset by -0.5 degrees (19-19.5 added to the current position). NOTE: The new value must be within the limits of the motor.

MOVE :

/SCALE

Scale provides the conversion factor from steps to whatever your useful units are. This is typically Steps/Degree. For the most part this value will be 2000., but other gear/reducer or 1/2-step combinations are possible. The syntax is 2THETA/SCALE 2000. WARNING!!! CHANGING THE SCALE CHANGES THE POSITION, THE BACKLASH, THE LIMITS. BE VERY CAREFUL WHEN CHANGING THE SCALE.

MOVE :

/SECONDS

This will move a motor in relative seconds rather than absolute position, ie 2THETA/SECONDS 10 will move 2theta + 10 seconds from its present position

MOVE :

/STEPS

This will move a motor in relative steps rather than absolute position, ie 2THETA/STEPS 10 will move 2theta + 10 steps from its present position.

MOVE :

/STRING

This command only works for Serial motors. It will pass the string directly to the rs232 port. The other way to do this is by SET HOST TTA0:/DTE at the prompt.

MOVE :

/UNL