FAST ComTec MCA4A User Manual

MCA4A

4 Input Multichannel Analyzer

2 Input Multichannel Scaler

User Manual

© Copyright FAST ComTec GmbH

Grünwalder Weg 28a, D-82041 Oberhaching

Germany

Version 2.09, October 25, 2018

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Software Warranty

FAST ComTec warrants proper operation of this software only when used with software and hardware
supplied by FAST ComTec. FAST ComTec assumes no responsibility for modifications made to this software
by third parties, or for the use or reliability of this software if used with hardware or software not supplied by
FAST ComTec. FAST ComTec makes no other warranty, expressed or implied, as to the merchantability or
fitness for an intended purpose of this software.

Software License

You have purchased the license to use this software, not the software itself. Since title to this software
remains with FAST ComTec, you may not sell or transfer this software. This license allows you to use this
software on only one compatible computer at a time. You must get FAST ComTec's written permission for
any exception to this license.

Backup Copy

This software is protected by German Copyright Law and by International Copyright Treaties. You have FAST
ComTec's express permission to make one archival copy of this software for backup protection. You may not
otherwise copy this software or any part of it for any other purpose.

Copyright © 2015-2018 FAST ComTec GmbH

D 82041 Oberhaching, Germany

All rights reserved

This manual contains proprietary information; no part of it may be reproduced by any means without prior
written permission of FAST ComTec, Grünwalder Weg 28a, D 82041 Oberhaching, Germany. Tel: ++49 89
66518050, FAX: ++49 89 66518040.

The information in this manual describes the hardware and the software as accurately as possible, but is
subject to change without notice.

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Table of Contents

1 Introduction.................................................................................................................................................... 9

2 Installation procedure................................................................................................................................... 10

2.1 Hard- and Software Requirements...................................................................................................... 10

2.2 Driver Installation................................................................................................................................. 11

2.3 Software Installation............................................................................................................................ 13

2.4 Hardware Installation........................................................................................................................... 13

2.5 Getting Started..................................................................................................................................... 14

2.5.1 Initial offset calibration................................................................................................................. 14

2.5.2 Basic Scope measurement.......................................................................................................... 16

2.5.3 Simple Pulse Height Analysis...................................................................................................... 19

2.5.4 Measuring a typical Pre-Amplifier Signal.....................................................................................22

2.5.5 Multiscaling measurement...........................................................................................................26

2.5.6 Basic Usage of the RealTimeClock Option.................................................................................. 28

2.6 Installing more than one MCA4A Module.............................................................................................29

3 Hardware Description.................................................................................................................................. 31

3.1 Overview.............................................................................................................................................. 31

3.2 Front Panel Connectors....................................................................................................................... 31

3.2.1 Analog ADC Inputs....................................................................................................................... 31

3.2.2 Changing the Input range............................................................................................................ 32

3.2.3 GATE / MCS Inputs...................................................................................................................... 33

3.2.4 FEATURE I/O Connector............................................................................................................. 34

3.3 MCA section, Analog-to-Digital Converter............................................................................................35

3.3.1 Scope mode................................................................................................................................. 35

3.3.2 Pulse height analysis................................................................................................................... 36

3.3.3 Sampled voltage analysis............................................................................................................38

3.3.4 Single channel analyzer (SCA).................................................................................................... 38

3.3.5 Real time, live time and system time counter...............................................................................38

3.3.6 List mode data acquisition........................................................................................................... 38

3.3.7 Event tagging, spectrum multiscaling.......................................................................................... 38

3.4 Multichannel scaler.............................................................................................................................. 39

3.4.1 Introduction.................................................................................................................................. 39

3.4.2 Dwell time.................................................................................................................................... 39

3.4.3 Sweep counter............................................................................................................................. 39

3.4.4 Spectrum sequencing.................................................................................................................. 39

3.5 Octal 125 MHz Counter / Timer........................................................................................................... 40

3.6 Time Base / Reference Clock.............................................................................................................. 40

4 Software Description.................................................................................................................................... 41

4.1 Server functions................................................................................................................................... 41

4.1.1 Initialization files .......................................................................................................................... 41

4.1.2 Action menus .............................................................................................................................. 42

4.1.3 File menu..................................................................................................................................... 42

4.1.4 Settings Overview........................................................................................................................ 44

4.1.5 MCS Settings............................................................................................................................... 45

4.1.6 Presets......................................................................................................................................... 46

4.1.7 ADC Settings............................................................................................................................... 47

4.1.8 Pulse-width histogramming.......................................................................................................... 51

4.1.9 Scaler Setting.............................................................................................................................. 52

4.1.10 System Definition....................................................................................................................... 53

4.1.11 Calculated Spectra dialog.......................................................................................................... 54

4.1.12 Conditions.................................................................................................................................. 58

4.2 File formats.......................................................................................................................................... 60

4.3 Control Language................................................................................................................................ 62

4.4 Controlling the MCA4 Windows Server via DDE.................................................................................. 68

4.4.1 Open Conversation...................................................................................................................... 68

4.4.2 DDE Execute............................................................................................................................... 68

4.4.3 Close Conversation..................................................................................................................... 70

4.5 Controlling the MCA4 Windows Server via DLL................................................................................... 72

5 MPANT Software......................................................................................................................................... 73

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5.1 File Menu............................................................................................................................................. 74

5.2 Window Menu...................................................................................................................................... 77

5.3 Region Menu....................................................................................................................................... 78

5.4 Options Menu...................................................................................................................................... 84

5.5 Action Menus....................................................................................................................................... 95

6 Programming and Software Options............................................................................................................ 97

7 Appendix...................................................................................................................................................... 98

7.1 Absolute Maximum Ratings................................................................................................................. 98

7.2 Recommended Operating Conditions.................................................................................................. 98

7.3 Specifications....................................................................................................................................... 98

7.3.1 ADC inputs................................................................................................................................... 98

7.3.2 GATE / MCS inputs...................................................................................................................... 98

7.3.3 SCA outputs................................................................................................................................. 99

7.3.4 Digital I/O ports............................................................................................................................ 99

7.3.5 Reference clock I/O..................................................................................................................... 99

7.3.6 Octal Counter inputs....................................................................................................................99

7.3.7 RTC RESET input........................................................................................................................ 99

7.4 Performance...................................................................................................................................... 100

7.4.1 General...................................................................................................................................... 100

7.4.2 Analog-to-Digital Converter........................................................................................................ 100

7.4.3 Counters.................................................................................................................................... 102

7.4.4 Multichannel scaler.................................................................................................................... 102

7.5 Physical............................................................................................................................................. 104

7.6 Accessories........................................................................................................................................ 104

Optional: ................................................................................................................................................. 104

7.7 Trouble Shooting................................................................................................................................ 105

7.8 Personal Notes.................................................................................................................................. 107

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Table of Figures

Fig. 2.1: Device Manager................................................................................................................................ 11

Fig. 2.2: Driver Installation.............................................................................................................................. 11

Fig. 2.3: Choosing the right folder................................................................................................................... 12

Fig. 2.4: Device Manager after successful driver installation..........................................................................12

Fig. 2.5: MCA4A rear panel............................................................................................................................. 13

Fig. 2.6: Software startup screen....................................................................................................................14

Fig. 2.7: MCA4A Settings window................................................................................................................... 14

Fig. 2.8: ADC Settings dialog (2x)................................................................................................................... 15

Fig. 2.9: ADC settings for the first measurement............................................................................................ 16

Fig. 2.10: Scale parameters for the scope display..........................................................................................17

Fig. 2.11: Scale parameters for the spectrum display.....................................................................................17

Fig. 2.12: 1st scope measurement.................................................................................................................. 18

Fig. 2.13: Single display options dialog........................................................................................................... 18

Fig. 2.14: Setup a FFT analysis...................................................................................................................... 19

Fig. 2.15: FFT analysis display....................................................................................................................... 19

Fig. 2.16: Setup a Gaussian Fit PHA measurement....................................................................................... 20

Fig. 2.17: Scope picture of a 1MHz sine wave................................................................................................ 20

Fig. 2.18: Switch to firmware based PHA........................................................................................................21

Fig. 2.19: Setup the internal Test Pulser.........................................................................................................22

Fig. 2.20: Setup the internal Test Pulser.........................................................................................................23

Fig. 2.21: Scope Picture of the original Test Pulser Signals............................................................................23

Fig. 2.22: Scope Picture of the internal Test Pulser........................................................................................24

Fig. 2.23: Scope Picture of the inverted and positive going Test Pulser Signals............................................24

Fig. 2.24: Enable the Trapezoidal Filter ......................................................................................................... 25

Fig. 2.25: Effects of different Pole Zero Settings.............................................................................................25

Fig. 2.26: Scope Picture of the trapezoidal shaped Test Pulser Signals......................................................... 25

Fig. 2.27: Modified shaper parameters........................................................................................................... 26

Fig. 2.28: MCA4 Settings: select MCS Mode.................................................................................................. 26

Fig. 2.29: MCS Settings for a simple measurement........................................................................................ 27

Fig. 2.30: Simple MCS spectrum.................................................................................................................... 27

Fig. 2.31: Basic RTC Experiment.................................................................................................................... 28

Fig. 2.32: Triggering the RTC with the TRG signal..........................................................................................28

Fig. 2.33: Basic Time Spectra......................................................................................................................... 29

Fig. 2.34: RTC Spectrum Definition................................................................................................................ 29

Fig. 2.35: Editing MCA4.INI............................................................................................................................ 30

Fig. 3.1: MCA4 front panel.............................................................................................................................. 31

Fig. 3.2: Left: jumper setting for different input ranges, right: jumper positions ..............................................32

Fig. 3.3: Simplified analog input and ADC circuitry......................................................................................... 32

Fig. 3.4: Circuit diagram of each GATE / MCS input....................................................................................... 33

Fig. 3.5: Circuit diagram of the FEATURE I/O port..........................................................................................34

Fig. 3.6: Digital I/O port details........................................................................................................................ 35

Fig. 3.7: GO-LINE details................................................................................................................................ 35

Fig. 3.8: Pulsewidth check - discard "false" pulses......................................................................................... 36

Fig. 3.9: Gaussian shaped pulse fitting........................................................................................................... 37

Fig. 3.10: Flattop pulse fitting modes..............................................................................................................37

Fig. 3.11: Pile-up detection............................................................................................................................. 38

Fig. 3.12: Octal 125 MHz Counter Connector................................................................................................. 40

Fig. 4.1: MCA4 Server Window....................................................................................................................... 41

Fig. 4.2: MCA4.ini File..................................................................................................................................... 42

Fig. 4.3: Data Operations dialog for MPA data (left) and selected spectra (right)...........................................43

Fig. 4.4: Replay Settings dialog...................................................................................................................... 43

Fig. 4.5: About MCA4 dialog box and Installed items...................................................................................... 44

Fig. 4.6: Settings overview, left: PHA mode, right: MCS mode, more than one MCA4 module.......................44

Fig. 4.7: MCS Settings for one (left) or two stop inputs (right)........................................................................45

Fig. 4.8: Thresholds Dialog............................................................................................................................. 46

Fig. 4.9: ADC Presets Dialog.......................................................................................................................... 46

Fig. 4.10: ADC Settings dialog, right: Scope mode.........................................................................................47

Fig. 4.11: Left: Setting Tag bits, right: advanced Settings...............................................................................49

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Fig. 4.12: Setting a ROI in the waveform for the pulse-height analysis of flattop pulses.................................50

Fig. 4.13: How to switch off Auto Scaling .......................................................................................................50

Fig. 4.14: Setting parameters for flattop PHA................................................................................................. 50

Fig. 4.15: Pulse Width Histogramming............................................................................................................ 51

Fig. 4.16 Scaler Settings dialog box............................................................................................................... 52

Fig. 4.17 Left: MCA4-Scaler Status utility, right: as ratemeter.........................................................................52

Fig. 4.18: System Definition dialog box........................................................................................................... 53

Fig. 4.19: Dual parameter and Calculated spectra dialog box........................................................................54

Fig. 4.20: Multi Display Setting....................................................................................................................... 54

Fig. 4.21: Multi Time Display Setting, left with installed RTC option and right without RTC option.................55

Fig. 4.22: Calculated Spectrum Setting, with (left) and without (right) RTC and Coincidence options............56

Fig. 4.23: Sum of Counts dialog...................................................................................................................... 56

Fig. 4.24: Sum of counts spectrum before and after calibration...................................................................... 57

Fig. 4.25: Conditions....................................................................................................................................... 58

Fig. 4.26: ROI Conditions dialog..................................................................................................................... 58

Fig. 4.27: Combine Conditions dialog.............................................................................................................58

Fig. 4.28: Conditions dialog with tag bits enabled........................................................................................... 59

Fig. 4.29: Tag Conditions dialog...................................................................................................................... 59

Fig. 4.30: Opening the DDE conversation with the MCA4 server in LabVIEW................................................68

Fig. 4.31: Executing a MCA4 command from a LabVIEW application............................................................69

Fig. 4.32: Getting the total number of spectrum data with LabVIEW..............................................................69

Fig. 4.33: Getting the data with LabVIEW....................................................................................................... 70

Fig. 4.34: Closing the DDE communication in LabVIEW.................................................................................70

Fig. 4.35: Control Panel of the demo VI for LabVIEW.....................................................................................71

Fig. 5.1: MPANT main window........................................................................................................................ 73

Fig. 5.2: MPANT Map and Isometric display...................................................................................................74

Fig. 5.3: File New Display dialog..................................................................................................................... 75

Fig. 5.4: Compare dialog................................................................................................................................. 76

Fig. 5.5: Compare two spectra........................................................................................................................ 76

Fig. 5.6: Print dialog........................................................................................................................................ 77

Fig. 5.7: Slice and rectangular ROI Editing dialog.......................................................................................... 80

Fig. 5.8: Polygonal ROI Editing dialog............................................................................................................ 80

Fig. 5.9: Single Gaussian Peak Fit.................................................................................................................. 81

Fig. 5.10: Evaluation of a non-Gaussian peak................................................................................................82

Fig. 5.11: Log file Options............................................................................................................................... 82

Fig. 5.12: Colors dialog................................................................................................................................... 84

Fig. 5.13: Color Palette dialog......................................................................................................................... 84

Fig. 5.14: Single Display Options dialog ........................................................................................................ 85

Fig. 5.15: Map Display Options dialog............................................................................................................ 86

Fig. 5.16: Isometric Display Options dialog..................................................................................................... 86

Fig. 5.17: Axis Parameters dialog................................................................................................................... 87

Fig. 5.18: Scale Parameters dialog................................................................................................................. 88

Fig. 5.19: Calibration dialog............................................................................................................................ 89

Fig. 5.20: Comments dialog............................................................................................................................90

Fig. 5.21: Settings dialog................................................................................................................................ 91

Fig. 5.22: Data Operations dialog................................................................................................................... 91

Fig. 5.23: System Definition dialog................................................................................................................. 92

Fig. 5.24: Spectra dialog................................................................................................................................. 92

Fig. 5.25: Slice dialog...................................................................................................................................... 93

Fig. 5.26: Replay dialog.................................................................................................................................. 93

Fig. 5.27: Tool Bar dialog................................................................................................................................ 94

Fig. 5.28: Function keys dialog....................................................................................................................... 94

Fig. 5.29: MPANT with four systems enabled................................................................................................. 96

Fig. 7.1: ADC noise spectrum (generated with a ramp generator and Gaussian fit).....................................101

Fig. 7.2: ADC integral linearity plot for 32k ADC range.................................................................................101

Fig. 7.3: ADC differential non-linearity plot for 32k ADC range.....................................................................101

Fig. 7.4: ADC DNL distribution...................................................................................................................... 101

Fig. 7.5: Typical peak widths of Gaussian fitted pulses (32k range, 4µs shaping)........................................102

Fig. 7.6: MCS noise spectrum (32k range, 50ns dwelltime)..........................................................................103

Fig. 7.7: MCS differential non-linearity plot (32k range, 50ns dwelltime)......................................................103

Fig. 7.8: MCS DNL distribution...................................................................................................................... 104

Fig. 7.9: Counter Cable BNC or Lemo.......................................................................................................... 105

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Introduction

1 Introduction

The MCA4A series is a versatile family of advanced USB3.0-connected, software controlled Multichannel
Analyzers and Multiscalers.

The design is capable of converting incoming analog pulses (PHA mode) on up to 4 channels at virtually no
conversion induced dead-time. Pulse Height Analysis can be performed using different fitting algorithms
optimized for different input pulse forms and shaping times. A digital Pole Zero Filter and Trapezoidal Pulse
Shaper enables to even process typical Pre-Amplifier signals.

PHA data is transferred via the USB 3.0 interface in list-mode at a max. rate of > 1 M events / sec on each
input. Four continuously, every 8 ns sampling 16 bit ADCs with extraordinary stability enable 32k resolution
for PHA mode.

The availabilty of the simultaneous usage of the oscilloscope (Scope) mode together with a Fast Fourier
Transformation (FFT) and software pulse height analysis allows for an easy setup and evaluation of the
experiment.

The PHA data can be tagged with the 8 digital I/O bits and also with the 8ns Real Time Clock.

A set of eight 125MHz Counter/Scalers is also provided.

In Multiscaling (MCS) mode the internal memory is used to accumulate spectra of up to 16M bins. An
automatic sequential mode allows to acquire up to 65536 sequential spectra – each with a presettable
number of sweeps – with no dead-time between each cycle or synchronized with an external signal. The
maximum count rate is 400 MHz, dwelltime is > 30 ns for one STOP input or > 50 ns for two STOP inputs.

A versatile 8 bit digital I/O port provides controlling external devices or to react on additional external signals.

The “GO-LINE” compatibility allows to synchronize begin and end of the experiment across many
measurement devices.

The 32 bit or 64 bit MPANT Windows Software is able to handle 6 MCA4A providing up to 24 MCA channels.
In-field upgrade options enable upgrading of MCS mode, more MCA channels, 8 ns RTC time tagging, and
multiparameter coincidences for 2 or 4 ADCs including Replay of list files.

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Installation procedure

2 Installation procedure

2.1 Hard- and Software Requirements

For operating the MCA4A you need a standard PC with a high-speed USB 2.0 or USB 3.0 port and Microsoft
Windows XP or higher. USB 1.0 ports do not work. The maximum throughput rate is approximately 32
Mbyte/sec on a USB 2.0 port and 120 Mbyte/sec on a USB 3.0 port. This throughput rate is somewhat
dependent on the computer hardware and operating system.

We do not expect any problems with host compatibility as we do not use something else than any USB hard
disk or memory stick. Of course, it is necessary that the PC has a true USB 2.0 or USB 3.0 / USB 3.1 port.

Older PCs that do not have USB 3.0 on the motherboard can use a PCI / PCIe card providing USB 3.0 /
USB 3.1 Gen1 ports.

First check you have all shipped equipment available:

• Transport case

• MCA4A module

• Power supply module 100…240 V AC / 12 V DC out

• Power line cord

• USB 3.0 (A/A) cable, 3 m

• User manual

• CDR or USB stick with operating software

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Installation procedure

2.2 Driver Installation

To install the driver, please start the device manager. You can do it by right-clicking the computer shortcut on
the desktop and selecting ”Manage” from the drop-down-menu, then ”Device Manager”. Another way is to
select in the Start Menu Settings..Control Panel, then System..Device Manager.

The new device is displayed as ”FX3” in a class ”Other devices”. Please right-click it and select ”Update
driver” from the drop-down menu.

Windows offers to search automatically for updated driver software or browse the computer for the driver
software. Don’t try the automatic installation, it will probably not work. Select to browse manually for the
driver and select for example for Windows 7 or 8 or 10 the driver\fastusb3 on the CD or Software stick. If you
have an MCA4 that you want to operate with the same software, please install the driver in the
driver\fastusb2 folder.

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Fig. 2.2: Driver Installation

Fig. 2.1: Device Manager

Installation procedure

Please don’t go deeper into the folder structure, the processor type (x86, amd64, etc.) is found automatically.
After pressing ”OK” the driver installation will proceed. The device manager will then show a ”FAST ComTec
USB3 Device” in a class ”libusb (WINUSB) devices” as shown in Fig. 2.4.

If there is a exclamation mark at the driver and there is an error message that the device could not start,
please remove the power from the MCA4A device and reconnect it. If you don't see the device at all, it is
possible that the USB3 driver must be updated. For a Renesas USB3 controller there is an update program
on the software disk in the driver\Renesas folder.

Please check the Power Saving Options in the PC Settings. If the PC goes to sleep during a running
acquisition and shuts the USB port down, the software will hang up. So it is recommended to disable
automatic going to sleep in the energy options.

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Fig. 2.3: Choosing the right folder

Fig. 2.4: Device Manager after successful driver installation

Installation procedure

2.3 Software Installation

To install the MCA4A software on your hard disk insert the installation medium (CD or USB Stick) and start
the installation program setup.exe for the 32-bit software or setupx64.exe for the native 64-bit software.

A directory called C:\MCA4A for the 32-bit software or C:\mca4ax64 for the native 64-bit software is created
on the hard disk and all MCA4A and MPANT files are transferred to this directory. Drive C: is taken as default
drive and \mca4ax64 as default directory. It is not mandatory that the MCA4A operating software is located in
this directory. You may specify a different directory during the installation or may copy the files later to any
other directory.

The Setup program will install a shortcut on the desktop. The icon directly starts MCA4A.EXE. The server
program will automatically call the MPANT.EXE program when it is executed. The MCA4A Server program
controls the MCA4A module but provides no graphics display capability by itself. By using the MPANT
program, the user has complete control of the MCA4A along with the MPANT display capabilities.

To run the MCA4A software, simply double click on the “MCA4A Server Program“ icon. To close it, close the
MCA4A server in the Taskbar.

2.4 Hardware Installation

Installation of the MCA4A is as easy as connecting a cable. As the USB 3.0 interface is compatible to USB

2.0 it is just a question of the maximum transfer speed which cables or host ports are used. Connect the
power supply to the “POWER” connector and an USB cable to the “USB” port. At the host computer plug in
the USB cable into a high-speed capable USB port. Since USB is a hot-pluggable interface the sequence of
applying power and connecting the USB port is not important.

When the power is applied the “POWER ON” LED on the rear of the MCA4A should be lit and a second later
“POWER GOOD” as well.

When the software and driver are already installed the computer will detect the MCA4A automatically as
soon as it is connected.

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Fig. 2.5: MCA4A rear panel

Installation procedure

2.5 Getting Started

2.5.1 Initial offset calibration

First step is to start the MCA4A software by double clicking the corresponding icon. This will automatically
start the MPANT program as well. On startup the MCA4A Server is iconized and one does not have to worry
about it since all hardware settings are accessible from the MPANT program which actually is the graphical
user interface and which will appear now on your screen.

At the very first start of the software and the MCA4A a calibration of the internal hardware based offsets
should be performed and the resulting data stored. Click on Options – Hardware Settings... or (ref. Fig.

2.6) to find the MCA4A Settings window pop up (Fig. 2.7).

Here select PHA Mode and then click on ADC Settings... to get the ADC Settings dialog window (ref. Fig. 2.8

- left).

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Fig. 2.7: MCA4A Settings window

Fig. 2.6: Software startup screen

Installation procedure

Make sure you have no signals connected to the MCA4A inputs! Click Get Zero and then Apply to perform a
measurement of the input offsets. The zero value is expected to be somewhere around 3,200.

Since the MCA4A provides unipolar, bipolar, negative unipolar and negative bipolar input ranges now switch
to the Neg. unipolar range by selecting advanced settings – Neg. unipolar Pulse polarity. If you have more
than one ADC input you may set the same polarity for all inputs simultaneously by clicking the Set All button.
You will be asked if you want new offsets for all channels, then new zero offsets are measured automatically
after Pulse polarity switching for all channels. The zero value (offset) should be in the magnitude of some
62,000 now (ref. Fig. 2.8 - right hand side). For the bipolar input range the zero value should be around
32,000.

Switch back to the positive unipolar input range, click Apply or Set All and OK and in the MCA4A Settings
(ref. Fig. 2.7) dialog on Save to store the measured offset data.

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Fig. 2.8: ADC Settings dialog (2x)

Installation procedure

2.5.2 Basic Scope measurement

This might be the best thing to start with. In case you don't know the details of your input signals you have
the option to watch and analyze them like with any oscilloscope. You will be able to find problems with the
setup like ringing or reflections. Even defective cables can be identified. It is also easy to adjust your
amplifiers' offset and pole zero settings without the need of an additional oscilloscope.

We use a standard waveform generator (e.g. 10kHz square wave) connected to the “ADC 1” input (ref. Fig.

3.1).

In the MPANT window click on Options – Hardware Settings... or (ref. Fig. 2.6) to find the MCA4A
Settings window pop up (Fig. 2.7. Here select PHA Mode and then click on ADC Settings... to get the ADC
Settings and Presets dialog window.

Referring Fig. 2.9 do Enable ADC input channel 1 (Chn: a_1). Choose PHA – Flattop to allow pulse height
analysis of the square wave signal. Set Scope-Mode - Scope-Mode, Rising edge, Trigger: CH1 and the
length of the scope window (here the maximum range of 32768). The trigger Threshold is set to 53.8mV.

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NOTE:

A calibration of the internal offsets (zero values) for all input ranges (pos. unipolar, bipolar and neg. unipolar
Pulse polarity) should be performed at the first startup
Please let the MCA4A warm up for some 30 minutes before calibration is performed

Fig. 2.9: ADC settings for the first measurement

Installation procedure

Before we will start the measurement we first set the display windows scalings.

Click on the scope display window (A1 (3) in Fig. 2.12) to make it the active window in MPANT. Select
Options – Scale parameters... or click and set the Counts Range to 0 … 65535 and deselct Auto scale
and Minimum auto scale (ref. Fig. 2.10). Press OK. This makes sure we will see the full 16 bit ADC
conversion range.

After activation of the spectrum display (a_1 (2) in Fig. 2.12) again select Options – Scale parameters... and
enable Autoscale (ref. Fig. 2.11). Press OK.

Now select Action1 – Start or click and start our first measurement. halts the measurment.

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Fig. 2.10: Scale parameters for the scope display

Fig. 2.11: Scale parameters for the spectrum display

Installation procedure

In the upper client window (A1) you see the scope picture of our square wave while in the lower (a_1) the
spectrum of the analysed pulse height is displayed.

Holding the left mouse button in a display window does set and move the cursor which values are shown just
below the x-scale. Hold the right mouse button to spread a range selection which can be used to zoom into
the window.

If the trigger threshold was not chosen properly and no sampling begins then select Trigger: auto. Measure
the sampled signal by holding the left mouse button and use the cursor values below the scope window x­scale to find a good value for the trigger threshold and revert to normal CH1 trigger.

Looking at Fig. 2.12 one can easily see the square wave had an amplitude of some 4.8V with little over- and
undershoot at the edges. The amplitude was stable enough which can be seen from the narrow peak
(needle) in the lower pulse height analysis spectrum.

An additional feature is the provision of a Fast Fourier Transformation. This shows the input signal in the
frequency domain. It helps to find noise pickup or parasitic signal sources that would downgrade
experimental results.

Activate the scope window (A1) and click on Options – Display... or to get the Single Display Options
dialog (Fig. 2.13).

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Fig. 2.12: 1st scope measurement

Fig. 2.13: Single display options dialog

Installation procedure

Here select Custom Formula... to get the Custom-transformed spectra setup. Choose Formula #: 6 (ref. Fig.

2.14, left side) which is the FFT and click Create.

This creates a third display window containing the Fast Fourier Transformation data (ref. Fig. 2.15). Most
probably you might want to switch the scaling from linear to logarithmic or vice versa (use the button).

2.5.3 Simple Pulse Height Analysis

We already did analyse the pulse height of a square wave signal in the previous chapter. Since we had the
scope mode active we did the PHA in software. Now we will setup an experiment using the internal firmware
based pulse height analysis. This provides far higher conversion rates (> 1MHz) without loss.

We use a general sine wave generator. The upper half of a sine wave actually does not look so different from
a Gaussian shaped amplifier signal. We set the frequency to 1MHz, the offset such that the signal is mostly
in the positive voltage range. E.g. set the amplitude to 6VPP and the Offset to 3V. Connect the signal to the
ADC 1 input (ref. Fig. 3.1).

First we want to verify what the input signal actually looks like. In the MPANT window click on Options –
Hardware Settings... or and select Scope-Mode with a range of 4096 and Trigger = CH1. As PHA fit
algorithm choose Gaussian. We also need to select the shaping time. After the first measurement you can
get help selecting the proper shaping time with the guess button (ref. Fig. 2.16). For a 1MHz sine wave

0.5 µs is a good choice. Clock OK.

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Fig. 2.14: Setup a FFT analysis

Fig. 2.15: FFT analysis display

Installation procedure

Select Action1 – Start or click and start the scope measurement - halts the measurement. The
resulting picture is in Fig. 2.17. You clearly see the sine wave with 1MHz and 6VPP amplitude. The PHA
spectrum below shows a rising peak near channel 5559.

As can be seen near the mouse pointer the converted signal rate is only some 2kHz. To be able to process
higher pulse rates the firmware based PHA fitting must be enabled and scope mode switched off.

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Fig. 2.17: Scope picture of a 1MHz sine wave

Fig. 2.16: Setup a Gaussian Fit PHA measurement

Installation procedure

Again go to the ADC Settings and Presets dialog and deselect Scope-Mode (ref. Fig. 2.18).

Now only one display (the PHA spectrum) remains in the MPANT window. After starting the measurement
again a peak begins to rise approximately at channel 5559 and you can see a data rate of almost 1MHz. This
rate depends a bit on the computer and the USB hubs used.

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Fig. 2.18: Switch to firmware based PHA

Installation procedure

2.5.4 Measuring a typical Pre-Amplifier Signal

We will now use the MCA4A's internal test pulser to produce pre-amplifier like input signals and setup the
pole zero filter and the trapezoidal shaper.

Since most pre-amplifier signals are typically negative we switch to the negative unipolar pulse polarity and
use the scope mode to see how the input signals look like. In the ADC Settings dialog select Neg. unipolar,
set PHA to Maximum and Scope-Mode with Falling edge trigger. Then setup the Shaper with Software (ref.
Fig. 2.19).

When clicking into the Testpulser.. checkbox a Test pulser setup window opens. Setup the pulser with a fast
rise time of "2", a long fall time of "200", an amplitude setting of "50" and a period of "5" x 32.8µs as in Fig.

2.20.

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Fig. 2.19: Setup the internal Test Pulser

Installation procedure

Starting the measurement we see the negative going input pulses as in Fig. 2.21.

Now switch to Firmware based shaping (ref. Fig. 2.22). This inverts the input signals which is necessary
since the firmware based shaping and pulse height analysis procedures are applicable for positive going
pulses only.

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Fig. 2.20: Setup the internal Test Pulser

Fig. 2.21: Scope Picture of the original Test Pulser Signals

Installation procedure

Now we can see positive going, inverted signals that are applicable to the firmware shaping and analysis
procedures.

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Fig. 2.22: Scope Picture of the internal Test Pulser

Fig. 2.23: Scope Picture of the inverted and positive going Test Pulser Signals

Installation procedure

In the ADC Settings dialog enable the Trapezoidal Filter (ref. Fig. 2.24).

The resulting scope picture shows the trapezoidal shaped pre-amplifier pulses as in Fig. 2.26. With the now
open Pole Zero Adjust window you may change the settings of the pole zero filter and optimize the resulting
shaped pulse form.

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Fig. 2.24: Enable the Trapezoidal Filter

Fig. 2.26: Scope Picture of the trapezoidal shaped Test Pulser Signals

Fig. 2.25: Effects of different Pole Zero Settings

Installation procedure

Also try to optimize the Peaking and Gap samples. In Fig. 2.27 you see the resulting waveform with Peaking
samples = 40 and Gap samples = 80.

2.5.5 Multiscaling measurement

To setup a simple multiscaling measurement we need a square wave generator that provides 2 synchronous
signals. This can be achieved with e.g. a function generator with additional SYNC output. Or you use 1 signal
that is connected via a power splitter to the MCA4.

In our example we have a function generator that is set to square wave with 0...3.3V amplitude like a low
voltage TTL signal and a frequency of 100kHz. We connect the signal output to STOP 1 and the SYNC
output to START.

Now click on Options – Hardware Settings... or to get the MCA4 Settings dialog pop up. Select Mode –
MCS and click on MCS Settings... (ref. Fig. 2.28) to get to the MCS Settings window (Fig. 2.29).

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Fig. 2.28: MCA4 Settings: select MCS Mode

Fig. 2.27: Modified shaper parameters

Installation procedure

Set Range = 1024, Dwelltime = 100ns, MCS Inputs Polarity to TTL, Impedance = 50 Ohm and click OK.

After starting the measurement a garden fence like spectrum begins to grow (ref. Fig. 2.30). The distance of
the peaks is 100 channels corresponding to 100 x 100ns = 10µs or 100kHz.

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Fig. 2.29: MCS Settings for a simple measurement

Fig. 2.30: Simple MCS spectrum

Installation procedure

2.5.6 Basic Usage of the RealTimeClock Option

To familiarize with the usage of the RealTimeClock (RTC) option a simple experiment is setup. The intention
is to measure the arrival time of single ADC events relatively to a start (trigger) signal like it might be done in
Time-of-Flight or similar experiments. To do so a variable delay is used to shift analog output pulses relatively
to the TTL trigger pulse that on the other hand resets (reloads) the RTC via the RTC RESET (TRG) input.
Thus, in terms of TOF, the trigger signal acts as start and the ADC signal as stop input. The delay time is
then measured with a resolution of 8 ns (or 1 msec if the 8 ns RTC option is not enabled) and a time
spectrum of the very ADC is accumulated.

The RTC is set to reload (restart) with a RTC RESET signal at the TRG connector (ref. Fig. 2.32). The timer
value capture command is derived from ADC 1 signal crossing the threshold. On-board Histogramming must
be disabled so the event data contain a time stamp. If you have the RTC option for that channel, the time
stamp is in units of 8 ns, otherwise in units of 1 msec.

The TRG is a 50 Ohm terminated TTL input.

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Fig. 2.31: Basic RTC Experiment

Fig. 2.32: Triggering the RTC with the TRG signal

Installation procedure

To visualize the timing relationship a spectrum is defined that shows the arrival time on the x-axis, the ADC
pulse height on the y-axis and the count rate in z-direction (ref. Fig. 2.34). Also a one dimensional spectrum
is defined (set ADC range to 1) to show just a time spectrum (projection onto the x-axis).

In Fig. 2.33 the resulting spectra can be seen. Watching the map display (window (4)) amplitude variations
show up as vertical lines whereas delay time variations result in horizontal lines. Window (6) is the
corresponding three-dimensional view, window (5) the pulse height analysis and (3) the time spectrum. The
acquisition will not start before a trigger signal is sent to the TRG connector at the rear panel. The Real timer
is reset by each new signal there, so the real time cannot longer be used for normalizing. The system time,
computer run time and live time may be used instead of it. The trigger signal should be a short pulse. For
high polarity, the RTC is stopped and hold at zero as long as the signal level is high, and the acquisition is
inhibited. After the pulse the acquisition is running for the time the signal level remains low.

2.6 Installing more than one MCA4A Module

The software is able to operate up to 6 MCA4A modules with a single computer. Just connect them at an
USB port, switch on the power, and install the driver when you are prompted. When starting the software,
you will be asked to edit the MCA4.INI file as more than one MCA4A modules are found, and the notepad
editor will be automatically started with MCA4.INI loaded. Edit the line "devices=1" accordingly and save the
file.

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Fig. 2.34: RTC Spectrum Definition

Fig. 2.33: Basic Time Spectra

Installation procedure

That is all you have to do, next time when you start the software all modules will be found and can be
operated.

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Fig. 2.35: Editing MCA4.INI

Hardware Description

3 Hardware Description

3.1 Overview

The MCA4A series is a family of USB 3.0 (compatible with USB 2.0) connected multichannel analyzers. All
settings are software selectable. No jumper (except for the optional ADC full scale ranges), switch etc.
configurations are necessary.

A 1GBit internal DDR2 RAM is configurable as large FIFO buffer for listmode data transfer or as
histogramming memory for onboard spectrum acquisition.

Four onboard discriminators at the four rightmost BNC connectors allow for either positive or negative
GATE / MCS input signals. The input voltage range is from -1.2 V to + 5.0V. The corresponding threshold
voltages are software selectable in steps of 1mV. The input impedance can be switched between 50 Ohm to
GND and 4.7kOhm with either pull-down or pull-up to +3.3V.

Four outputs at the feature connector provide several selectable signals (e.g. SCA, BUSY, etc.) for external
usage.

The legendary 'GO'-line (compatible with other FAST ComTec products) allows for easy synchronization or
triggering of other measurement equipment.

Furthermore a versatile 8 bit digital I/O port allows for a whole bunch of experimental control, monitoring or
whatsoever other tasks. Moreover, the 8 bit digital I/O port can be used for event and spectra tagging to
allow for multi-detector configurations, sequential data acquisition etc.

3.2 Front Panel Connectors

3.2.1 Analog ADC Inputs

The analog ADC inputs are 4 BNC type connectors on the front panel of the MCA4A. Each is paired with a
green LED that indicates that the input is active. They accept negativ or positiv uni-polar or bi-polar signals.

The input signal is continuously sampled by a 125MHz / 16bit (11, 12, 13 bit options are available) analog-to­digital converter. The converted data is buffered in a 32k x 16bit FIFO for subsequent evaluation. This buffer
FIFO can be segmented in 1, 2, 4 or 8 equal partitions. Each segment holding the complete data of a
detected input pulse for evaluation. This allows for virtually dead-time-less conversion as incoming pulses
can be stored while a previous pulse is still processed by the PHA fitting algorithms. In absolute maximum
mode (no fit) actually no conversion induced dead time exists.

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Fig. 3.1: MCA4 front panel

Hardware Description

3.2.2 Changing the Input range

The full scale voltage range is jumper selectable between 2.0V, 2.5V, 8.0V and 10.0V (default).

The default setting is 10 V corresponding to a VPP value of 11019 (mV) for the full 16 bit range 0..65535.
This value can be edited in the ADC settings, if the “advanced Settings” checkbox is crossed, see Fig. 4.11.
Standard values for the 8 V, 2.5 V and 2 V ranges are 8875, 2640 and 2120. Enter the new VPP value if you
have changed the input range and save it. You can do a precise calibration of VPP if you connect a DC
voltage U to the input that you measure by a good digital voltmeter and get the corresponding value V(U) by
clicking the “Get Zero” button. The VPP value is then

VPP = U * 65535 / (V(U) – V(0)).

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Fig. 3.3: Simplified analog input and ADC circuitry

Fig. 3.2: Left: jumper setting for different input ranges, right: jumper positions

Hardware Description

3.2.3 GATE / MCS Inputs

The GATE / MCS inputs provide a switchable 4.7kOhm pullup to +3.3V, 4.7kOhm pulldown to GND or
50Ohm to GND input impedance. Each input is equipped with a fast discriminator. The threshold level can be
chosen from +1.3V for TTL signals or -300mV for fast NIM signals.

In PHA mode these inputs can be used as GATE. PHA event gating is evaluated at the threshold crossing.
COINC and ANTI coincidence is available.

In SVA mode the selected edge of the GATE signal samples the corresponding ADC input signal.

In MCS mode these inputs are used as START, STOP 1 & 2 and external channel advance (CHADV).

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Fig. 3.4: Circuit diagram of each GATE / MCS input

NOTE:

For clean switching and oscillation free operation the input slew rate should be higher than 25V/µs.

Hardware Description

3.2.4 FEATURE I/O Connector

Single-channel-analyzer (SCA) Outputs

When a maximum1 of the sampled analog ADC data is detected the corresponding maximum value is
evaluated for lower- and upper-level thresholds (LLD and ULD). If the maximum falls in between LLD and
ULD the pulse is accepted as valid and a SCA output pulse of 120 ns is initiated.

Other signals can be selected at the nominal SCA ports:

1. SCA (120ns pulse for each valid SCA event)

2. ADC BUSY (over-the-threshold OR input FIFO full → dead time)

3. GATE input signal (as discriminated)

4. MCS event (2.5ns pulse for each detected count edge)

5. SVA event (as internally validated)

6. ...

Digital I/O ports

A very versatile 8 bit digital I/O port is implemented on the FEATURE I/O connector. Since the corresponding
resistors are socket mounted they can be easily user configured in a most flexible way.

This I/O port is fully software controllable and each single (1-bit) port is individually configurable. It might be
used for external alerts, sample changer control, status input / outputs, spectrum / event tagging, etc.

As can be seen from Fig. 3.6 each individual bit might be configured as input only (tri-stated output), pull-up
(open drain) or driver output (small R-I/O) with readback capability. Wired OR / AND connections are
feasible.

1 A peak maximum is detected when the actual input data is 6% lower than the previous maximum value since the threshold crossing

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Fig. 3.5: Circuit diagram of the FEATURE I/O port

Hardware Description

GO-Line

The system-wide open-drain wired-AND 'GO-Line' enables any connected device to start and stop all
participating measurment equipment simultanously. The 'GO' line may be enabled, disabled, set and reset
under software control.

3.3 MCA section, Analog-to-Digital Converter

The 16bit analog to digital converter samples the input signals at a continous 125MHz rate.

The data can be evaluated in several ways. Each input channel might be configured independently.

• Scope mode

• Pulse height analysis (PHA)

• Sampled voltage analysis (SVA)

3.3.1 Scope mode

After a trigger event scope pictures of 4k, 8k, 16k or 32k data samples are acquired.

The trigger source can be chosen from channel 1, 2, 3, 4 or external (START input). The trigger edge (rising
or falling) is also selectable.

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Fig. 3.7: GO-LINE details

Fig. 3.6: Digital I/O port details

Hardware Description

The available trigger modes are SINGLE, NORMAL and AUTO.

In SINGLE mode only the first trigger event is displayed. In NORMAL mode subsequent trigger events start a
new display. In AUTO mode the measurement is triggered by real trigger events or - in absence of those ­automatically.

For further evaluation FFT and software PHA are available (ref. chapter 5 MPANT Software).

Be aware that due to the large number of data being transferred the effective event rate is low compared to a
firmware based (onboard) pulse height analysis. Thus, the scope mode is mostly for setting up the
experiment.

3.3.2 Pulse height analysis

Onboard (firmware based) signal evaluation and pulse height analysis allows for high event rates and only
little conversion induced dead time.

The incoming ADC data stream is evaluated for a rising edge threshold crossing which is taken as the start
of a pulse. The input signal is sampled at 8ns intervals and the data is stored in the 32k input buffer FIFO.
This 32k buffer FIFO is segmentable in 1, 2, 4 or 8 equal sized segments. This provides for virtually no
analysis induced dead-time as a new pulse can be stored while a previous is still processed.

After the input signal fell below the threshold again the pulse sampling is finished and processing begins.
Optionally a hysteresis for the threshold crossings can be chosen. This might improve the spectrum for low
amplitudes, slowly falling input pulses and high noise levels.

Each PHA event is tagged with the RTC (1ms or optionally 8ns) and – if selected – the TAG inputs at the
pulse start. The tagging is executed at the leading edge threshold crossing.

After detecting a completed input pulse the stored data is checked for the minimum and maximum number of
samples. This enables to discard false (too short and too long) pulses (ref. Fig. 3.8). Then the data is
evaluated using the selected fitting algorithm.

Absolute maximum (none):

No calculation is necessary and the absolute maximum value is taken.

Fit for Gaussian shaped pulses:

A curve is fitted through the selected number of samples (2 x i1 + 1) around the absolute maximum. This
provides for a reduction of noise and thus, better peak widths in the acquired spectrum.

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Note:

In scope mode a small data FIFO size should be chosen (ref. Fig. 4.6 ) for better display response

Fig. 3.8: Pulsewidth check - discard "false" pulses

Hardware Description

The conversion time (ref. chapter 7.4.2 ) depends on the number of samples used for the fit.

Flat top pulse fitting:

For flattop pulses a chosen number of samples is averaged. The area (start and end) of the averaged data is
software selectable.

Three different modes are selectable for defining the averaging area (ref. Fig. 3.10).

Mode 1 (left edge) is good for pulse forms that settle near the beginning

Mode 2 (right edge) is good for pulse forms that settle towards the end.

Mode 3 (CFT) is particularly useful when the pulse width is largely dependent on the pulse height.

Pile-up rejection

A pile-up rejection feature is implemented. The incoming data is checked for a possible second peak before
the signal fell below the threshold again (ref. Fig. 3.11). If such a second peak is detected the pulse data is
marked with a “pile-up detected” flag. It is also possible to discard the event without analyzing it further, i.e.
no fitting is performed, when this feature is enabled (ref. chapter 4.1.7 ADC Settings and Fig. 4.11).

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NOTE:

The optimum number of samples used for the fit depends on the shaping time of the input pulses.

Fig. 3.10: Flattop pulse fitting modes

Fig. 3.9: Gaussian shaped pulse fitting

Hardware Description

A second option to discard pile-up events is to use the GATE input as REJECT signal if the external
electronics (e.g. pre-amplifier) provides such a signal. In this mode an active REJECT signal while the ADC
input signal is above the threshold (i.e. a pulse is active) discards the very event.

3.3.3 Sampled voltage analysis

In SVA mode the corresponding GATE input is used to initiate the sampling of the current analog input
voltage. The rising or falling edge of the GATE signal is selectable.

Simultaneously each SVA event is tagged with the RTC (1ms or optionally 8ns) and – if selected – the TAG
inputs.

3.3.4 Single channel analyzer (SCA)

When a maximum of the input signal is detected the corresponding absolute maximum value is checked if it
falls in between the lower and upper threshold levels. If so, a 120ns long SCA pulse is generated. This is
available at the FEATURE I/O connector (ref. Fig. 3.5).

3.3.5 Real time, live time and system time counter

Each of the 4 ADC channels is equipped with 2 independent and presettable 48 bit counters. Also a 48 bit
and presettable system timer is provided.

The timer counters provide a resolution of 1ms (8ns with RTC option).

Each pulse event is tagged with the corresponding system time value when the leading edge threshold
occurs.

3.3.6 List mode data acquisition

The analyzed data (pulse height) is patched with additional information like event time, TAG bits or pulse
width and transferred to the computer in 64 bit words per event.

3.3.7 Event tagging, spectrum multiscaling

The 8 digital I/O ports can be used for event tagging as well. Each bit is individually selectable. The digital
I/O line reading is continuously updated every 2.5µs.

In PHA mode of operation the digital I/O port reading is sampled at the leading edge threshold crossing.

38 F ComTec GmbH

Fig. 3.11: Pile-up detection

Hardware Description

3.4 Multichannel scaler

3.4.1 Introduction

In MCS mode of operation the MCA4 counts STOP events relative to the START (trigger) signal. The time
resolution is equal to the selected dwell time. The total measurement time is the spectrum length in time bins
multiplied by the dwell time. The maximum STOP count rate is 400MHz.

The maximum number of time bins (spectrum length) is 16M. It can be selected in steps of 1. This time
granularity allows to optimize the sweep length for the specific experiment.

Histogramming is performed in the onboard DDR2 memory providing the low dwell times (30 ns / 50 ns) and
high count rates (400 MHz).

3.4.2 Dwell time

The internal dwell timer provides automatic time bin advancement in the range of min. 30ns (1 channel MCS)
or min. 50ns (dual channel MCS) up to ((248 – 1) x 10ns) = 781h in steps of 10ns.

External channel advance is supported via the corresponding CHADV input. Please note that the external
channel advance signal is internally synchronized to a free running 100MHz clock. An integrated control
circuitry assures the minimum cycle time of 100ns, thus guaranteeing no triggering on too fast, ringing or
spiky signals.

3.4.3 Sweep counter

The presettable sweep counter is 48 bit wide and increments on each valid START (trigger) event.

3.4.4 Spectrum sequencing

Sequences of spectra consisting of a preset number of sweeps may be automatically generated.

The number of sequences is in the range of 2 to 65536.

When the preset number of sweeps is accumulated the sequence counter is incremented and a new set of
sweeps is started.

F ComTec GmbH 39

Hardware Description

3.5 Octal 125 MHz Counter / Timer

The MCA4A includes eight 48bit synchronous 125 MHz up-/down-counters. 2 counters are presettable.

All inputs are TTL like and are terminated with 50Ω to ground. For each counter input the polarity is software
selectable.

The counters actually either count the software selected rising or falling COUNT input edges (counter mode)
or work as 125 MHz timers (RTC option is required).

Counting can be individually gated or switched between up- and down-counting by the individual GATE
inputs. Also a common gate is provided. The usage can be individually selected for each channel.

Also a common LOAD is individually selectable. This actually clears the chosen counters.

The system wide GO-Line may also control the counting action. This can be set individually for each counter.

3.6 Time Base / Reference Clock

The internal reference is a 10 MHz crystal oscillator. This can be output at the CLK rear side BNC connector.
Or an external clock signal may be used. This external reference frequency might be in the range from 5 to
100 MHz in steps of 1 MHz.

40 F ComTec GmbH

Fig. 3.12: Octal 125 MHz Counter Connector

Software Description

4 Software Description

The software is a layer of several parts. A driver (WINUSB.SYS) provides the communication via the USB
port. A server program (MCA4A.EXE) controls the hardware and the data. A graphical user interface
(MPANT.EXE) controls the server via a DLL (DMCA4.DLL) and provides graphical displays. This chapter
describes now the server program.

The window of the MCA4 server program is shown here. It enables the full control of the MCA4A to perform
measurements and save data. This program has no own spectra display, but it provides - via a DLL
(”dynamic link library”) - access to all functions, parameters and data. The server can be completely
controlled from the MPANT software that provides all necessary graphic displays. The view of the server
window depends on the number of active input channels, here all 4 ADC channels are active.

4.1 Server functions

To start the software, just double click a shortcut icon linking to the server program. The server program
performs a test whether the hardware works well on this computer, then starts MPANT and gets iconized.
Usually you will control everything from MPANT, but it is possible to work with the server alone and
independently from MPANT.

4.1.1 Initialization files

At program start the configuration files MCA4.INI and MCA4A.SET are loaded.

Parameters that can be set by editing the MCA4.INI file are the update rate in msec for the refresh of the
status, and the voltage calibration factors. The number of ADC channels and resolution is set automatically.

The file MCA4A.SET contains the default settings. It is not necessary to edit this file since it is saved
automatically. Instead of this .SET file any other setup file can be used if its name without the appendix
‘A.SET’ is used as command line parameter (e.g. MCA4 TEST to load TESTA.SET). The command line
parameter can be used either by calling the program from a “DOS box” or by changing the properties of an
icon on the desktop that points to the program.

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Fig. 4.1: MCA4 Server Window

Software Description

4.1.2 Action menus

The server program normally is shown as an icon in the taskbar. After clicking the icon it is opened to show
the status window. Using the “Start” menu item from the Action1 menu a measurement can be started. In the
status window every second the acquired events, the counting rate and the time are shown. Clicking the
“Halt” menu item the measurement is stopped and via “Continue” proceeded. As it is possible in the System
Settings dialog to create up to four systems each containing different MCA's combined for simultaneous
starting and stopping, there are four Action menus Action1..Action4.

4.1.3 File menu

Clicking in the File menu on the Data... item opens the Data Operations dialog box.

This dialog allows to edit the data format settings and perform operations like Save, Load, Add, Subtract,
Smooth and Erase.

The Radio Buttons MPA, Selected Spectra and New Spectra provide a choice between handling of the
complete data set (MPA) or selected spectra, or to load new selected spectra for compare.

Mark the checkbox Save at Halt to write a MPA file containing the configuration and all spectra at the stop of
a measurement. The file name can be entered. If the checkbox auto incr. is crossed, a 3-digit number is
appended to the file name that is automatically incremented with each saving. The format of the data can be
ASCII (extension for separated spectra .ASC), binary (.DAT), GANAAS (.SPE), EMSA (.EMSA) and CSV
(.CSV).

If Separate Header is not checked, the Header and data is saved together in a file with extension .MP,
otherwise the file with extension .MP contains only the header and the data is written separately into a file
with appropriate extension.

The buttons Save, Load, and Erase perform the respective operation. With Add and Sub spectra can be
added or subtracted from the present data. The checkbox calibr. can be checked to use a calibration and to
shift the data then according to the calibration. The Smooth button performs an n-point smoothing of
selected single spectra. The number of points to average can be set with the Pts edit field between 2 and 21.
Check the Write Listfile checkbox to write a listfile during a run. No Histogramming prevents calculating
any spectra to save computing time and concentrate the system on writing the list file.

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Fig. 4.2: MCA4.ini File

Software Description

The menu item File – Replay... opens the Replay dialog. It enables evaluation of list data. The Replay
software licence is usually programmed into the MCA4 module or by an optional USB dongle.

Enable Replay Mode using the checkbox and specify a File name of a list file (extension .LST) or search
one by pressing Browse... With the radio buttons it is possible either to choose the complete list file by
selecting All or a selected Start# Range. Specify the sweep range by editing the respective edit fields from:
and Preset: . The Replay Speed can be specified in units of 100 kB per sec. To Use Modified Settings
enable the corresponding checkbox; otherwise the original settings are used. To start Replay press then
Start in the Action menu or the corresponding MPANT toolbar icon.

The menu item File – About... opens the About MCA4 window where some information of the System can be
found. Particularly the serial number is important for support purposes. This serial number is unique for each
MCA4 system. A click on the “Installed...” button opens a dialog showing all installed features.

F ComTec GmbH 43

Fig. 4.3: Data Operations dialog for MPA data (left) and selected spectra (right)

Fig. 4.4: Replay Settings dialog

Software Description

The MPANT menu item in the file menu starts the MPANT program if it is not running.

4.1.4 Settings Overview

The Hardware... item in the Settings menu opens the MCA4 Settings dialog box. It enables to switch
between PHA mode (left figure) and MCS mode (right). If more than one MCA module are installed, the
module (A, B,..) can be selected in the upper right corner as shown right in Fig. 4.6.

Via the SCA - combo boxes you can specify the signal you want to observe at the feature connector. See
chapter 3.2.4. You can observe for each channel the SCA, ADC BUSY (over-the-threshold), GATE Input,
MCS Input or SVA event signals.

In PHA mode a List file can be written by checking the corresponding checkbox Write Listfile. The data
format can be ASCII or binary depending on the format settings in the data operations dialog. The FIFO size
can be selected between Full (128 Mb), Medium (32 Mb) and Small (8 Mb). For real data acquisition the full
size is recommended. For adjusting parameters when using Scope mode, a small FIFO size is useful as
changes can be observed immediately whereas with a full FIFO size they are delayed by several seconds.

OK takes all settings and closes the dialog. Apply sets all settings without closing the dialog. Cancel cancels
all changes. Pressing Save writes all settings into the file MCA4A.SET and MCA4_###.set resp. the entered
setup name. The file name is built by attaching “A.set” and “_###.set” to the shown name, where “###” is the
serial number of the MCA4. Browse lets you search for settings files, Load Sett. loads one. When loading a
settings file, the file with the serial number fitting to the device in the file name is loaded if one is found,
otherwise or when the software is running in demo mode the file MCA4A.SET for the first MCA4 module.

44 F ComTec GmbH

Fig. 4.5: About MCA4 dialog box and Installed items

Fig. 4.6: Settings overview, left: PHA mode, right: MCS mode, more than one MCA4 module.

Software Description

4.1.5 MCS Settings

Clicking the MCS Settings button opens the MCS Settings or MCS2 Settings dialog as shown in Fig. 4.7.
The Range defines the number of time bins, the Dwelltime can be set in units of 10 ns from 30 ns (MCS) or
50 ns (MCS2). The measurement can be stopped automatically after a specified number of sweeps by
checking Sweep preset. If the checkbox ROI Preset is marked, the measurement will be stopped after
acquiring more events than specified in the interval between the boundaries defined in the corresponding
edit fields. The events are counted only if they are within the ROI limits, i.e. >= the lower limit and < the upper
limit. Another possibility is to acquire data for a given time via the Time Preset.

A series of measurements can be acquired into separate memory parts by checking Sequential cycles and
specifying the number of cycles. Each single measurement should be terminated preferably by a sweep
preset condition. The complete run stops after performing the specified number of cycles. The spectra are
then shown in a two dimensional view row by row in the MPANT program. As the sequential mode is
implemented in the firmware, there is only a very small delay of 30 ns between the time spectra when using
a sweep preset.

For some measurements it is desired to synchronize the sequential cycles to an external signal from a
sample changer or target mover. This can also be done by using the Digital I/O port together with the
“waitpin” command. Just define any of the function toolbar icons in the MPANT program by a command like
oncycle waitpin 3000 and click on this toolbar icon. Now in sequential mode when a sweep preset is
reached after each individual cycle, the acquisition stops until the voltage level at Dig I/O 7 gets low. If the
voltage is still high after 3000 msec, a message box will pop up and warn that a time out happened. See
section 4.3 about more details and on the syntax of control language commands.

F ComTec GmbH 45

Fig. 4.7: MCS Settings for one (left) or two stop inputs (right)

Software Description

For the MCS Inputs the Polarity can be selected between TTL and ECL (NIM) signals. For each of the MCS
inputs you can select between the rising and the falling edge. Usually for TTL signals, rising edge should be
active and for (negative) fast NIM signals “rising edge” should be deselected as the leading edge has the
better timing.

OK takes the settings and closes the dialog. Apply sets the parameters in the hardware without closing the
dialog. Cancel closes the dialog and cancels all changes.

The input thresholds can be set individually for each input. Click the “Thresholds...” button to open the
Thresholds dialog.

4.1.6 Presets

Clicking the Presets checkbox in the Settings dialog opens the ADC Presets dialog as shown in Fig. 4.10.
Here all preset parameters for PHA mode and SVA mode can be set. Select the ADC in the drop-down
listbox at top right. If the checkbox ROIpreset is marked, the measurement will be stopped after acquiring
more events than specified in the corresponding edit field. The Counts are events counted by the hardware
that trigger a pulse height analysis, whereas the ROI events are counted in the software if the corresponding
data in the spectrum are within the ROI2 boundaries, i.e. >= the lower limit ROI min and < the upper limit ROI
max that can be defined in the ADC Settings dialog. Another possibility is to acquire data for a given run time
via the RTimepreset or a given live time via the LTimepreset. A measurement will be stopped if the
corresponding checkbox is marked.

2 ROI: Region Of Interest

46 F ComTec GmbH

Fig. 4.9: ADC Presets Dialog

Fig. 4.8: Thresholds Dialog

Software Description

4.1.7 ADC Settings

Clicking the ADC Settings button in the Settings overview the ADC Settings dialog as shown in Fig. 4.10.
Here all parameters like range, etc. for PHA mode and SVA mode can be set. Select the ADC in the drop­down listbox at top right. The Enable checkbox must be checked if the corresponding channel is active. The
ADC resolution and length of the spectrum is set by the Range listbox between 2 and 65536 in binary steps.
For the Gate input there is a choice between Don't Use, COINC, ANTI and REJ IN.

COINC means that the voltage level at the Gate input must be high to trigger an event, ANTI means that the
level must be low. A pull-up resistor in COINC mode and a pull-down resistor in ANTI mode lets the input
work if no gate input is connected, see . The gating is evaluated at the time of the threshold crossing. Set All
sets the range and Gate mode for all ADC's.

The SCA3 boundaries can be set with the SCA Lower, Upper edit fields. Here the units are in LSB's of the 16­bit ADC, i.e. full range is from 0 to 65535. If an event is recorded inside the SCA boundaries, a pulse signal
can be output at the corresponding monitor output at the feature connector.

The Threshold for triggering an event can be set in mV, an event will be triggered if the voltage level crosses
the zero plus threshold level. The Get Zero button calibrates the offset voltage level. It is recommended to
connect no signal when doing this offset calibration. The offsets will be saved into the default settings file
MCA4A.SET by clicking “Save” in the hardware settings dialog, and automatically reloaded when the
software is started next time. See chapter 2.5.1. As the offset calibration can cause a shift in the spectrum,
be careful not to do a new “Get Zero” within a series of measurements. The pulse height spectrum shown in
the MPANT program is an histogram of the ADC data, the offset is subtracted. Therefore the maximum pulse
height value that can be recorded when using a 64k range is 64k minus the zero value. The maximum

3 SCA: Single-channel-analyzer

F ComTec GmbH 47

Fig. 4.10: ADC Settings dialog, right: Scope mode

Software Description

spectrum range is therefore somewhat less than the binary range set, so the spectrum length shown in the
MPANT program is correspondingly reduced and the spectrum will be new painted when a new “Get Zero”
calibration is done.

The MCA4A is able either to record the waveform and send the complete waveform data (Scope Mode) or to
do a pulse height analysis and just send the result. The maximum count rate is of course much lower in
Scope mode, therefore this mode is used for optimizing the electronics like adjusting a pole zero in the
amplifier and also selecting the parameters for the PHA (pulse-height analysis). See chapters 2.5.2 and

2.5.3.

Select Scope-Mode to inspect your signal as shown in the right part of Fig. 4.10. New elements appear now
in the dialog for editing the waveform length and the trigger parameters. The waveform length can be
selected between 4k, 8k, 16k and 32k. The unit is 8 ns, so the waveform length is between 32 µs and
262 µs. For the Triggering you can set the Source and Trigger Mode. For the first check use the channel
corresponding to the ADC as trigger source, i.e. CH1 for ADC a_1, and Normal as trigger mode. Now close
all dialog boxes with OK and do a short acquisition by clicking the Start toolbar icon in the MPANT program.
You should get a view of the waveform of your pulses. If you now go back into the ADC Settings dialog, a
new button “guess” will appear beside the Shaping listbox in the PHA box. If you click that button, a
recommended value for the shaping time will be selected to get a first choice for the PHA parameters.

The trigger source in Scope-Mode can be selected between Software, CH1, CH2, CH3, CH4 and Extern
(START). “Software” means that an event will be triggered by the software as often as possible. “Extern
Trigger” means a signal connected at the START / GATE1 input. When using the Extern trigger new edit
elements appear in the “SVA-Mode / Extern Trigger” box for the Polarity, Impedance and Edge of the START
input discriminator.

The Trigger Mode can be Normal, Auto and Single Shot. “Auto” means that a software trigger will be done if
no trigger event is detected. “Single Shot” means that the acquisition is stopped after a single trigger event.
To do this, an event count preset of 1 is set. The Pretrigger can be selected between none, 30 samples, 100
samples and 250 samples.

Check SVA-Mode if you want to do a sampled voltage analysis. In this mode an external trigger signal
samples a voltage conversion. The same trigger parameters like polarity, impedance, edge can be set as for
the external trigger. For ADC1 the START / GATE1 input is used, for ADC2 the STOP1 / GATE2 input and so
on. SVA-mode disables automatically Scope-Mode and PHA, in the PHA box “Maximum” will be selected.

The 8 Digital I/O ports (Feature connector) can be used as Tag bits if this checkbox is selected and the
respective licence is enabled. A new edit field for the number of tag bits (select between 1 and 8) appears in
the Tagbits box and a drop-down select box for One Hot, Binary and Don't show. “Don't show” means that
the tag bits are only in the list data but not shown.

“One hot” means that a two dimensional spectrum is acquired with the tag bits as y-coordinate. See Fig.

4.11. For eight tag bits there will be 10 rows of the data array. The first row contains the spectrum if no tag bit
was detected. The second row is the spectrum with tag bit 0 set only, the next row is the spectrum with tag
bit 1 set and so on, last row contains the spectrum when more than one tag bit is set.

If Sequential mode is selected in the Presets dialog, there is an option “next cycle with tag 0 toggle”. This
enables to acquire very short measurements synchronized to an external signal without any deadtime, for
example to acquire PIXE images. See in the readme.txt at Server version 1.62 about a DLL that can be
called at every cycle switching to do fast evaluations. An example named hvcycle.dll is part of the shipped
software, the source code is part of the DLL software interface.

“Binary” means the y-coordinate is the value if the tag bits are seen as a binary number. In this case for 8 tag
bits the y-dimension of the 2D spectrum is 256. Tag bits can be used in PHA mode, Scope mode and SVA
mode. As the digital I/O port is used, the other functions using the digital I/O port like external controlled Start
/ Stop of an acquisition are not available together with Tag bits.

48 F ComTec GmbH

Software Description

If you check advanced Settings more options will appear for the PHA parameters. VPP (mV) is the voltage
corresponding to the full range of the ADC from 0 to 65535 LSB's. You can change it if you have a calibrated
value for example by connecting a DC voltage to the ADC input that is known very well for example by using
a good digital volt meter. The THL hysteresis can be selected between “none”, “15 LSB”, “30 LSB” and “50
LSB”. The value means that the voltage level at the input must go below the threshold by the respective
value before a new pulse will be triggered. The threshold level hysteresis prevents triggering again on
spurious signals when crossing the threshold after a pulse. The recommended value depends on the noise
level, a value of 30 LSB is recommended, especially for signals that have a slow falling time and when using
the “Maximum” method.

The Fit width is the most important parameter that influences the quality of the pulse-height analysis of
Gaussian shaped pulses, see Fig. 3.9. This Fit width and the limits Width min, max for the fit range are set
when choosing a Shaping time from the list box. You may play with the Fit width parameter and see if you
can improve the resolution of your pulses by setting a value corresponding to a shaping time in between of
those in the list. If your pulses are shaped with a rather long shaping time, it could be necessary to increase
the max Width of the Fit range to get a successful PHA result.

For Flattop pulses it is necessary to specify a ROI at the top of the waveform for calculating the mean value
as PHA result, see Fig. 4.12. To get such a zoomed picture of the pulse at its top region, first switch off the
Auto scale and Minimum auto scale in the Scale options dialog of the MPANT program (Fig. 4.13). Then set

Y-Slice for the Region Shape by clicking the corresponding toolbar icon and while keeping the right mouse
button pressed, drag a zooming rectangle over the interesting region at the top of the waveform, then click
the “Zoom in” icon . To define the ROI, switch back to X-Slice for the Region Shape using the
corresponding icon . Then drag the ROI boundaries from left to right keeping the right mouse button
pressed and click the “Create ROI” icon . To take over the ROI parameters into the flattop PHA, click the
from ROI button shown in Fig. 4.14. There is a choice of anchoring the ROI either at the left edge of the
pulse, the right edge, or the left ROI boundary at a constant fraction between right and left edge, by selecting
CFT in the listbox. The edges are determined by the time when the signal crosses the threshold. It depends

F ComTec GmbH 49

Fig. 4.11: Left: Setting Tag bits, right: advanced Settings

Software Description

on the electronics creating the flattop pulses, which method of anchoring the ROI gives the best result for a
varying pulse height.

50 F ComTec GmbH

Fig. 4.12: Setting a ROI in the waveform for the pulse-height analysis of flattop pulses

Fig. 4.13: How to switch off Auto Scaling

Fig. 4.14: Setting parameters for flattop PHA

Software Description

4.1.8 Pulse-width histogramming

The pulse width of the analog input pulse at the threshold level can be measured in units of 64 ns, the pulse
width data is inserted into the highest 12 bits of the RTC data, the length of the timestamp data is then only
32 bits instead of 44 bits. A histogram of the pulse width distribution can be acquired, and a two dimensional
spectrum showing the pulse height versus pulse width can be created. It is possible to reject events if the
pulse width is larger than a specified limit. See in Fig. 4.15 how to create a pulse width histogram and set a
limit for the maximum pulse width. Note that if “Reject” is enabled, the data is still in the list file and the event
is rejected only in the histograms. So when evaluating a list file, the pulse width limit still can be changed.

F ComTec GmbH 51

Fig. 4.15: Pulse Width Histogramming

Software Description

4.1.9 Scaler Setting

The “Scaler Settings...” button in the settings overview opens the respective dialog box to define the use of
the 8 125 MHz Scaler/Counters. This is an option, see chapter 3.5 . A utility program mca4scal.exe is started
automatically and shows the scaler values, optionally as a ratemeter. The scalers can be individually named,
the values are saved into the data file. For an exact synchronizing of start and stop of the scalers with the
acquisition it is recommended to enable Count gated with GO and Remove GO when Preset reached.
Furthermore, the three checkboxes concerning the GO-line in the system definition dialog should be crossed,
see chapter 4.1.10 .

52 F ComTec GmbH

Fig. 4.16 Scaler Settings dialog box

Fig. 4.17 Left: MCA4-Scaler Status utility, right: as ratemeter

Software Description

4.1.10 System Definition

The “System...” item in the settings menu opens the System Definition dialog box. S everal MCA's can be
combined to form up to 4 separate systems that can be started, stopped and erased together. The use of the
Digital Input / Output and the GO-Line can be defined: It can be used either to show the ON or OFF status of
the systems if the checkbox Status Dig 0..3 is marked. At the respective pins +5 Volt are output if an
acquisition is running and 0 V if not. Alternatively, it can be used for example with a sample changer by
checking "Value inc. at Stop". Here, the 8-bit value entered in the edit field (a number between 0 and 255) is
output at the Dig I/O port. This value will always be incremented by 1 if the MCA4 is stopped. The Invert
checkbox allows inverting the logical level. See also the commands pulse and waitpin how to handshake a
sample changer or synchronize sequential cycles with a target mover, see the control language in 4.3. The
Radio buttons Push-Pull and Open Drain define the output mode of the Dig I/O ports.

It is also possible to use the digital input 4 as an external trigger for starting the system (DESY control line). If
the corresponding checkbox Start with Dig 4 is marked, a start command for the respective system will not
immediately start the system. After the start command, the digital input will be permanently checked for its
logical level. If the level changes from high to low, the data for the system is cleared and it will then be
started. It will stop if the level returns to high (or vice versa if Invert is marked) and can again be restarted
with the next level change. A stop command for the system will finish the digital input checking. By checking
Clear before Start the spectra is cleared before the start. As an alternative to controlling Start/stop via digital
input 4 also the GO-line can be used by checking Start with GO. This is better as the GO-line controls the
hardware directly.

The Use of the GO-Line is controlled via the 3 checkboxes Watch, High when ON, and Low at Stop. The GO
line gates directly the hardware. "Low at Stop" means that the GO line is immediately pulled down by the
hardware when a sweep preset is reached, or as fast as possible by the software at any other stop. If Tag
bits are used, the digital I/O port is used as an input for the tag bits exclusively, see chapter 4.1.7.

F ComTec GmbH 53

Fig. 4.18: System Definition dialog box

Software Description

4.1.11 Calculated Spectra dialog

Dependent on installed options like RTC and Coincidence Mode the MCA4 software allows to create several
calculated spectra from different channels. By clicking "Spectra..." in the Settings menu or the corresponding
MPANT toolbar icon the Dualparameter and Calculated Spectra dialog box of the MCA4 server is called.
Here additional dual parameter and calculated spectra can be added, modified and deleted from the list.
Since firmware 5.16 it is possible to create a 2D view of the pulse height versus the pulse width if pulse width
histogramming is enabled, by a “Add Shape” button.

If the 8 ns RTC for at least two channels and Coincidence mode options are installed, there is a “ Add Multi”
button. If pressed, the Multi Display Settings dialog opens. It allows to define dual parameter spectra
showing coincident events from two ADC inputs. The coincidence is recognized by the software if events
from different ADC have a RTC value that is inside a specified coincidence time interval.

For the x Axis and y Axis a Parameter and Range must be chosen from the respective drop down list. You
can edit a Name of the new multi spectra, or you can left the 'Name' edit field untouched to choose an
automatically generated name like a_1 x a_2. The length of the Coincidence time window can be defined in
units of µs. If Conditions are defined, one can be selected as a necessary Condition for incrementing a
channel in this dual-parameter spectra. See more about Conditions later in 4.1.12. For zoomed Maps check
the x Offset and y Offset checkbox and enter a value for the respective Offsets and Compression. The Offset

54 F ComTec GmbH

Fig. 4.19: Dual parameter and Calculated spectra dialog box

Fig. 4.20: Multi Display Setting

Software Description

point marks the lower left corner of the zoomed map, and the Compr. by 2^n means the power of two by
which the spectra are compressed. A value of zero means full resolution.

Press Add Time to define a new Time spectrum in the Multi Time Display Settings dialog. For the x Axis and y
Axis a parameter and range must be chosen from the respective drop down list. The time axis can be either
the x Axis or the y Axis, select the respective radio button. The time parameter can be either a 1 msec Real
time or the 8 nsec RTC clock if the respective option is available. Define the Time Offset and Time Bin size in
the corresponding edit fields and Unit selection boxes. A Name can be entered for the new time spectra, or
you can left the 'Name' edit field untouched to choose an automatically generated name like RTC x a_1. The
checkbox Time Differences enables recording time spectra relative to an event in any selected ADC. For
zoomed Maps check the x Offset or y Offset checkbox and enter a value for the respective Offsets and
Compression. The Offset point marks the lower left corner of the zoomed map, and the Compr. by 2^n
means the power of two by which the spectra are compressed. A value of zero means full resolution. For a
one-dimensional time spectrum just use 1 for the ADC range.

Press Add Calc from the Map and Calculated Spectra dialog to define a new calculated single spectrum in
the Calculated Spectrum Setting dialog. Depending on installed RTC and Coincidence options, this dialog
comes up either as shown left or right in Fig. 4.22.

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Fig. 4.21: Multi Time Display Setting, left with installed RTC option and right without RTC option.

Software Description

You have a choice between several formulas to combine two parameters: Sum = left + right makes a sum
spectrum, and Diff = Range + left - right can be used to subtract two spectra. The Range and Name can be
defined in the edit fields or default values will be taken. Any such calculated spectrum can be used as a
parameter for a new dual parameter spectrum. If Conditions are defined, one can be selected as a
necessary Condition for incrementing a channel in this spectra. For ADC inputs in addition the Pos = Range *
right / (left + right) formula is available, that is often used for position dependent detectors read out from both
sides, and the Division formula Div = Range * left / right can be used to divide two spectra. The Range and
Name can be defined in the edit fields or default values will be taken. Any such calculated spectrum can be
used as a parameter for a multi parameter spectrum. If Conditions are defined, one can be selected as a
necessary Condition for incrementing a channel in this spectra. The COPY type of spectra allows to set
conditions for copies of primary ADC spectra. History allows to display a history plot of an ADC as a new
spectrum, i.e. you can see the data of the ADC as they come in versus the event number. The length of the
history plot can be defined free, just edit the Range number. Wrap around lets the history plot start new from
the left overwriting the old curve, when the right end is reached.

Spectra containing the sum of counts from several ADC's can be used to create a "superdetector" from
multiple smaller detectors. The sum spectrum is calculated from the complete single spectra. Select the "Or
= Sum of counts" radio button.

56 F ComTec GmbH

Fig. 4.22: Calculated Spectrum Setting, with (left) and without (right) RTC and Coincidence options

Fig. 4.23: Sum of Counts dialog

Software Description

In the "Sum of counts" dialog you can select which ADCs will contribute to the superdetector. It is
recommended to enable "Use Calibration" and to perform a careful calibration of all selected ADC's:

Make a short acquisition using a pulser or a calibration source so you get a peak in each used ADC. In each
ADC zoom into the spectrum, then by keeping the right mouse button pressed drag from left to right over the
peak to mark a fit region and click on the "Fit" toolbar icon to make a Gaussian peak fit. Note the position
value of the peak in the first ADC. For the first ADC you can just enable "Use Calibration" in the calibration
dialog and use the standard parameters p0=0, p1=1. In the next ADC enter two calibration points: for the first
point enter 0 for the Channel and 0 for the value and click "Add>>". For the second calibration point use the
result of the fit: Click "Fit" to enter the Channel value of the fitted peak position. For the "Value" enter the fit
result of the peak position in the first ADC. Click "Calibrate" and enable "Use Calibration", then click "OK".
Proceed this way until all used ADCs are calibrated. You will immediately get the effect: Instead of a peak
multiplet you will see a single sharp peak in the sum spectrum.

Another good method to enter the calibration is to draw in the second spectrum a ROI over the peak by
keeping the right mouse button pressed and clicking the “Create ROI” icon , then select “Region..Edit”
item from the MPANT menu, select the ROI in the list, enter the fit result from the first spectrum for the value
of the Calibration Peak and click “Modify” and “OK”. Then choose Region..Auto Calib in the MPANT menu.

The automatic generated spectra name is for example "OR_3_C". The 3 is here an hexadecimal bit pattern
indicating that ADC1 (bit 0) and ADC2 (bit 1) contribute to the OR sum. The C at the end of the name means
that "Use Calibration" is enabled.

F ComTec GmbH 57

Fig. 4.24: Sum of counts spectrum before and after calibration

Software Description

4.1.12 Conditions

If the RTC and Coincidence options are enabled, press Conditions... from the "Dualparameter and
Calculated Spectra" dialog to define or edit ROI Conditions in the Conditions dialog.

To define a new condition, press Add Roi... to open the ROI Condition dialog.

Here it is possible to define a Condition as an event inside or outside of an ROI in any parameter spectrum
i.e. a calculated parameter or a "copy" of a primary spectrum. There are two drop-down list boxes for the
Parameter and ROI. Of course the ROI must be defined before by using the MPANT program, it is not
possible here to add any new ROI. A checkbox labeled NOT in ROI allows to define a condition as an event
outside the ROI. Using the edit field Name it is possible to define a name for the Condition. A default name
built by the parameter name and ROI number will be set automatically.

Press Combine... to open the Combine Conditions dialog.

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Fig. 4.25: Conditions

Fig. 4.26: ROI Conditions dialog

Fig. 4.27: Combine Conditions dialog

Software Description

Here a Condition can be defined as a combination using the Boolean operators NOT, OR or AND of already
defined conditions. The OR will be symbolized in the automatically generated name by a plus sign "+", the
AND by an asterisk "*".

If tag bits are enabled in the user licence, it is also possible to define tag bit conditions. The conditions dialog
contains then a button Add Tag...

To define a new tag condition, press Add Tag... to open the Tag Condition dialog.

Here a Condition can be defined that is true for a special tag bit pattern. Two parameters Pattern and Mask
can be edited in hex format with two hexadecimal digits. The Mask defines which tag bits are used, and the
Pattern defines for which tag bit pattern the condition is true (or false if NOT is checked). The shown
example with Pattern=2 and Mask=fe is a condition that is true if tag bit 1 is ON and tag bits 2 to 7 are all
OFF, tag bit 0 does not care.

F ComTec GmbH 59

Fig. 4.28: Conditions dialog with tag bits enabled

Fig. 4.29: Tag Conditions dialog

Software Description

4.2 File formats

The .mpa format is used to save all spectra in a single file. It starts with an ASCII header containing the
settings and then the spectra follow one after the other, each proceeded with a header line like

[DATA0,16384 ]

(This means the first single spectrum with a length of 16384 channels.)

[DATA1,16384 ]

(This means the second single spectra...)

[CDAT0,16384]

(This is the first dual parameter or calculated spectra with a length of 16384 channels. The enumeration
starts again at zero after all "physical" spectra.)

The format of the data itself can be ASCII, Binary, GANAAS, EMSA or CSV (see below). Individual spectra
can also be saved into single files. If "separate header" is checked in the data operations dialog, such
spectra data is written into two separate files, one with extension .mp containing configuration data and one
containing pure spectra data with an extension indicating the chosen format. The .mp file contains the
settings in ASCII format using the control language described in section 4.3

Spectra data files with extension .asc contain in each line one decimal number in ASCII containing the
corresponding count value in the histogram.

Binary data files with extension .dat are written with 4 bytes per data value, as usual in the Intel world in
reverse order i.e. the least significant byte comes first.

GANAAS data files with extension .spe contain 10 data in ASCII format after a simple header. This format is
used by the IAEA gamma spectra evaluation program GANAAS.

EMSA data files are in ASCII with extension .emsa and follow the NIST EMSA spectrum file format.

Another ASCII file format is the x y format with extension .csv. It can be read for example with Excel and
contains the channel number and content as two decimal numbers in ASCII per line separated by a TAB
character.

List files have the extension .lst and start with a header containing the usual report and configuration data in
ASCII as in the .mpa or .mp files. The header ends with a line containing [DATA].

Then follows the data, depending on the format chosen for the data file either in ASCII or binary. In ASCII
format one data word is written in hex format per line. In binary format each stop event is written with 8 bytes,
as usual in the Intel world in the reverse order, i.e. the least significant byte comes first. A single event is a 64
bit number (8 bytes), or in scope mode a multiple of such 8 byte numbers.

The lowest two bits 0 and 1 are the channel number 0..3 for ADC1..ADC4.

Bit 2 is a flag for pileup detected.

Bit 3 indicates scope mode. If it is on, more data words follow.

Bit 4 – 47 is a 44 bit event time. If the RTC option is enabled, it is in units of 8 ns, otherwise in units of 1
msec. With tag bits enabled, the 8 most significant event time bits are used for tagging and represent the 8
dig I/O input bits. If pulse width measurement is enabled, the most significant 12 bits are used for the pulse
width and represent the pulse width at the threshold level in units of 64 ns.

Bit 48 – 63 are the 16 bit ADC value or in scope mode the length of the waveform data minus one in units of
16 bit words. This size value can be 4095, 8191, 16383 or 32767. The waveform data follow then next.

Here is an example of list file data:

[DATA]
adf20000000266f0
ad4f0000000266f2
ae0c0000000266f3
ae820000000266f1
ae850000000573a1
ad500000000573b2
ae0e0000000573a3

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Software Description

The software adds at the end of a list file a small data block containing the counter values.

The format follow the scheme of scope mode data, it can be distinguished by the waveform length that is
only 12 16-bit words.

The lowest two bits 0 and 1 are the channel number 0..3 for ADC1..ADC4.

Bit 3 indicates scope mode. It is on, so more data words follow.

Bit 4 – 47 are zero.

Bit 48 – 63 are the length of the counter data minus one in units of 16 bit words. This size value is 11 or in
hex format b for 12 16-bit words or 3 64-bit counter data. The counter data follow then next, real time, live
time and event counter. The counter data are 64 bit values

Here is an example of a counter data block:

000b000000000008
0000000007735943
00000000075aacad
0000000000002710
000b000000000009
0000000007735943
00000000075aaed3
0000000000002710
000b00000000000a
0000000007735943
00000000075ab725
0000000000002710
000b00000000000b
0000000007735943
00000000075aaf24
0000000000002710

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Software Description

4.3 Control Language

A sequence of commands that are stored in a file with extension .CTL can be executed by the MCA4 server
program or MPANT with the “Load ” or “Run” command. Also the configuration files MCA4A.SET or the
header files with extension .MP contain such commands to set the parameters. Each command starts at the
beginning of a new line with a typical keyword, the case is ignored. Any other characters in a line may
contain a value or a comment.

Following methods are available to execute commands:

 Define one of programmable toolbar icons F1..F12 in the MPANT program with the command and

click the icon, see Options..Function keys in the MPANT menu.

 Load the command file using the Load command in the file menu.

 Enable remote mode in the server and send commands via the serial connection. A special DLL is

necessary which is part of the optional available MPANT EXTERNAL CONTROL software.

 Open a DDE connection and send the commands via DDE as described in section 4.4. The

application name for opening the DDE connection with the standard MCA4 server program
MCA4.EXE is MCA4, the topic is MCA4-. Implemented are the DDE Execute to perform any
command, and the DDE Request with items RANGE and DATA.

 Send the commands over a TCP/IP net using a remote shell and the optional available MPANT

EXTERNAL CONTROL software. It is necessary to have a TCP/IP Winsock installed and that the
remote shell daemon program MPA4NET is running. See the readme file on the installation disk.

 Send the commands via the DLL interface from LabVIEW, a Visual Basic program or any other

application (software including the complete source code of the DLL and examples optional
available).

 From your own Windows application, register a Windows message and then send the command

as can be seen in the DLL source code.

The file MCA4A.SET contains a complete list of commands for setting parameters. An example is:

[MCA4A] 104 ; Device and serial number
samplemode=10f ; bit 0..3 chn1..4 0: scope-mode, 1: phamode

; bit 4..7 chn1..4 pile-up reject

; bit 8: Software-PHA
enable_dither=1 ; enable dithering, improves the differential linearity of the ADC chip.
pr_ena=0 ; Preset enable flags, MCS mode:

; bit 0: runtime preset enabled

; bit 1: realtime preset enabled

; bit 2: sweep preset enabled

; bit 3: ROI preset enabled

; bit 5: ROI2 preset enabled
enb_ch=1 ; bit0..3: enable ADC chn1..chn4
thr1=ad20c62 ; LOWORD: threshold 1 HIWORD: zero in 64 bit ADC LSB's.
thr2=b370cc7 ; threshold 2 and zero
thr3=9dc0b6c ; threshold 3 and zero
thr4=9dc0b6c ; threshold 4 and zero
width1=531ffe ; LOWORD: maxwidth1 samples per pulse, HIWORD: minwidth1
width2=531ffe
width3=531ffe
width4=531ffe
digio=0 ; LOWORD: Use of Dig I/O, GO Line:

; bit 0: status dig 0..3

; bit 1: Output digval and increment digval after stop

; bit 2: Invert polarity

; bit 3: Push-Pull output

; bit 4: Start System 1 with Dig 4

; bit 5: Start System 1 with GO

; bit 8: GOWATCH

; bit 9: GO High at Start

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Software Description

; bit 10: GO Low at Stop

; bit 11: Clear before triggered start
digval=0 ; 0..255 DIG I/O Output value
trigger=6 ; bit 1..4 control_trigger for scope mode.

; bit 0: TRG_EDGE_DOWN

; bit 1: TRG_EDGE_UP

; bit 2..4: TRG_SRC,0=none (softw.), 1..4=CH1..4, 5=extern

; bit 5: 0=normal, 1=auto

; bit 6: single shot
mcsmode=0 ; bit 16: mcs mode

; bit 17: 2mcs mode

; bit 18: sequential mode

; bit 19: ext. clock
cycles=1 ; cycles for sequential mode
mcspol=10 ; bit 0: start with rising edge

; bit 1: stop1 rising edge

; bit 2: stop2 rising edge

; bit 3: ch adv rising edge

; bit 4: FAST NIM

; bit 5: 4k7 MCS Inputs
svapol=f ; for external trigger and SVA:

; bit 0: trigger / ch1 with rising edge

; bit 1: ch2 rising edge

; bit 2: ch3 rising edge

; bit 3: ch4 rising edge

; bit 4: FAST NIM

; bit 5: 1=4k7, 0=50 Ohm
dwellunit=0 ; choice of units in dialog 0=ns, 1=usec, 2=msec, 3=sec
dwelltime=10 ; in units of 10 ns
swpreset=10 ; sweep preset value
timepreset=10.000 ; time preset
unipolar=1 ; unipolar or bipolar (0)
event_cnt_mode=1 ; count only stored events
fifosize=0 ; 0=128 MB, 1=32 MB, 2=8 MB
sca1=ffff ; LOWORD: upperlevel SCA 1, HIWORD: lowerlevel SCA 1
sca2=ffff
sca3=ffff
sca4=ffff
phafit=0 ; bit0..1 chn1: 0=max, 1= fit, 2 flattop, 3 reserved

; bit2..3 chn2

; bit4..5 chn3

; bit6..7 chn4
fitwidth1=29 ; LOWORD: fitwidth gaussian, HIWORD, pulsewidth flattop
fitwidth2=29
fitwidth3=29
fitwidth4=29
memsegs=aa ; Bit0..1: SEGMENTS_CH1, 0..3 = 1x32k/2x16k/4x8k/8x4k segments

; Bit2..3: SEGMENTS_CH2

; Bit4..5: SEGMENTS_CH3

; Bit6..7: SEGMENTS_CH4
ctm8=125 ; coincidence time in units of 8 ns
mwidth1=0 ; flattop: range for Mean calc LOWORD upper, HIWORD lower
mwidth2=0 ; LOWORD: Bit0..13 meanrange, Bit(15,14) Method 0=left, 1=cft, 2=right
mwidth3=0 ; HIWORD: roileft
mwidth4=0
gate=0 ; bit 0..3: GATE_ADC1..4, 1=Gate must be active for pulse processing

; bit 4..7: GATE_POL1..4, 1=active high

; bit 8..11: REJECT_ADC1..4, 1=use GATE as reject, e.g. pile-up detected,

; cor. GATE_ADCx must be 0

; bit 12..15: SVA mode
ctlsca=0 ; bit 0..3: SCA_CH1, 0=SCA, 1=Over-Threshold, 2=GATE Input, 3=MCS Input

; bit 4..7: SCA_CH2,

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Software Description

; bit 8..11: SCA_CH3,

; bit 12..15 SCA_CH4
autoinc=0 ; 1=Enable Auto increment of filename
savedata=0 ; bit 0: auto save after stop

; bit 1: write listfile

; bit 2: listfile only, no evaluation

; bit 5: drop zero events
mpafmt=asc ; format used in mpa datafiles

; (dat=binary, asc=ASCII, csv=CSV, spe=GANAAS, emsa=EMSA)
sephead=0 ; seperate Header
fmt=dat ; data format used in separated spectra (extension MP)

; (dat=binary, asc=ASCII, csv=CSV, spe=GANAAS, emsa=EMSA
mpacaluse=0 ; use calibration for shifted summing .mpa files according to calibration
smoothpts=5 ; Number of points to average for a smooth operation
wndwidth=160 ; Sets width of server window
wndheight=24 ; Sets height of server window
sysdef=0 ; Defines which module belongs to a system, relevant only for more

; modules
[MCS1] ; MCS1 parameters
active=1 ; active
range=4096 ; spectrum length
[MCS2] ; MCS2 parameters
active=0 ; active
range=4096 ; spectrum length (same as MCS1 range)
[CHN1] ; Scopemode Channel 1 parameters
active=0 ; active
range=4096 ; waveform length
[CHN2]
active=0
range=4096
[CHN3]
active=0
range=4096
[CHN4]
active=0
range=4096
[ADC1] ; ADC1 parameters
active=1 ; active
range=16384 ; spectrum length
prena=0 ; bit 0: realtime preset enabled

; bit 1: livetime preset enabled

; bit 2: Event preset enabled

; bit 3: ROI preset enabled
roimin=0 ; lower ROI limit for ROI preset
roimax=16384 ; upper limit: roimin <= channel < roimax
evpreset=1 ; ROI preset or event count preset
rtpreset=1000.000 ; real time preset (sec)
ltpreset=1000.000 ; live time preset (sec)
bitshift=2 ; bit shift between ADC LSB's and spectrum resolution
caloff=0.000000 ; calibration parameter: offset
calfact=1.000000 ; calibration parameter: factor
calfact2=0
calfact3=0
calunit=keV ; calibration unit
caluse=0 ; bit 0=1: use calibration, higher bits: calibration formula
[ADC2] ; the following section concerns parameters of ADC2

...

The following commands perform actions and therefore usually are not included in the MCA4A.SET file:

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Software Description

start ; Clears the data and starts a new acquisition of system 1.

; Further execution of the .CTL file is suspended until any

; acquisition stops due to a preset.

halt ; Stops acquisition of system 1 if one is running.

cont ; Continues acquisition of system 1. If a time preset

; is already reached, the time preset is prolongated

; by the value which was valid when the “start“ command

; was executed. Further execution of the .CTL file

; is suspended (see start).

erase ; Clears all spectra of system 1.

savecnf ; Writes the settings into MCS6A.SET

savempa ; Saves all configuration and spectra data.

; An existing file is overwritten.

loadmpa ; Loads mpa data; the filename

; must be specified before with a command mpaname=...

addmpa ; Adds mpa data to actual spectra; the filename

; must be specified before with a command mpaname=...

submpa ; Subtracts mpa data from actual spectra; the filename

; must be specified before with a command mpaname=...

MC_A ; Sets actual input channel to MC_A (STOP1) for the rest of

; the control file.

MC_B ; Sets actual multichannel analyzer to MC_B (STOP2)

savedat ; Saves data of actual channel as separated

; spectrum (extension .MP) An existing file

; is overwritten.

loaddat ; Loads data of actual channel, the filename

; must be specified before with a command datname=...

adddat ; Adds data into actual spectra; the filename

; must be specified before with a command datname=...

subdat ; Subtracts data from actual spectra channel; the filename

; must be specified before with a command datname=...

smooth ; Smoothes the data in actual spectra

erase ; Clears the data of system 1.

exit ; Exits the server (and MPANT) programs

alert Message ; Displays a Messagebox containing Message and an OK

; button that must be pressed before execution can continue.

waitinfo 5000 Message ; Displays a Messagebox containing Message, an OK

; and an END button. After the specified time (5000 msec)

; the Messagebox vanishes and execution continues. OK

; continues immediately, END escapes execution.

beep * ; Makes a beep. The character '*' may be replaced with '?', '!' or

; left empty. The corresponding sound is defined in the WIN.INI

; file in the [sounds] section.

delay 4000 ; Waits specified time (4000 msec = 4 sec).

pulse 100 ; Outputs a pulse of 100 ms duration at dig 3.

waitpin 4000 ; Waits 4000 ms for going the level at dig 7 going low.

; After a timeout a Messagebox warns and waits for pressing OK

; Can be used for connecting a sample changer.

waitpin3 4000 ; waits for going the level at pin 3 going low. All Dig I/O ports 0..7

; can be used this way.

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Software Description

loadcnf configfile ; Loads a configuration stored in a config file like mca4a.set.

run controlfile ; Runs a sequence of commands stored in controlfile. This

; command cannot be nested, i.e. it is not possible to execute

; a run command from the controlfile called with a run command,

; only if it was called with a load command.

onstart command ; The command is executed always after a start action when the

; acquisition is already running. The command can be any valid

; command, also 'run controlfile' is possible.

onstart off ; Switches off the 'onstart' feature. Also a manual Stop command

; switches it off.

onstop command ; The command is executed always after a stop caused by a

; preset reached or trigger. This can be used to program measure

; cycles. For example the command 'onstop start' makes a

; loop of this kind.

onstop off ; Switches off the 'onstop' feature. Also a manual Stop command

; switches it off.

oncycle command ; The command is executed in sequential mode after each cycle.

; can be used together with 'waitpin' command to synchronize with a

; beam- or target mover.

oncycle off ; Switches off the 'oncycle' feature.

lastrun=5 ; Defines the file count for the last run in a measure cycle. After a

; file with this count or greater was saved with autoinc on, instead

; of the 'onstop command' the 'onlast command' is executed.

numruns=5 ; Defines the file count for the last run in a measure cycle. The

; last count is the present one plus the numruns number. After a

; file with this count was saved with autoinc on, instead of the

; 'onstop command' the 'onlast command' is executed.

onlast command ; The command is executed after a stop caused by a preset

; reached or trigger instead of the 'onstop command', when the

; last file count is reached with autoinc on. This can be used to

; finish programmed measure cycles.

onlast off ; Switches off the 'onlast' feature. Also a manual Stop command

; switches it off.

exec program ; Executes a Windows program or .PIF file.

; Example: exec notepad test.ctl

; opens the notepad editor and loads test.ctl.

fitrois ; Makes a single peak Gaussian fit for all ROIs in the active

; Display of MPANT and dumps the result into a logfile. This is

; performed by the MPANT program and therefore can be

; made only if this application is running.

fitrois MC_A ; Similar to the fitroi command, but using the argument allows to

; specify which spectrum should be evaluated independently of

; which child window is activated in MPANT. MC_A means STOP1

autocal ; Makes a single peak Gaussian fit for all ROIs in the active

; Display of MPANT for which a peak value was entered in the

; MPANT Region Edit dialog and uses the results for a

; calibration. This is performed by the MPANT program and

; therefore can be made only if this application is running.

autocal SP_1 ; Similar to the autocal command, but using the argument allows

; to specify which spectrum should be evaluated independently of

; which child window is activated in MPANT

deleteallrois ; deletes all ROIs in the active MPANT window.

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Software Description

deleteallrois MC_# ; allows to delete all ROIs of a specified spectra (1 for # means

; A1..).

The following commands make sense only when using the serial line or TCP/IP control or DLL control
interface:

MC_A? ; Sends the status of MC_A via the serial port and make it actual.

...

MC_H? ; Sends the status of MC_H via the serial port and

; make it actual.

? ; Send the status of the actual channel

sendfile filename ; Sends the ASCII file with name ‘filename’ via the serial line.

The execution of a control file can be finished from the Server or MPANT with any Halt command.

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Software Description

4.4 Controlling the MCA4 Windows Server via DDE

The MCA4 program can be a server for DDE (Dynamic Data Exchange). Many Windows software packages
can use the DDE standard protocols to communicate with other Windows programs, for example GRAMS,
FAMOS or LabVIEW. In the following the DDE capabilities of the MCA4 program are described together with
a demo VI (“Virtual Instrument”) for LabVIEW. It is not recommended to use the DDE protocol for LabVIEW,
as also a DLL interface is available that is much faster. The following should be seen as a general description
of the DDE conversation capabilities of the MCA4 server program.

4.4.1 Open Conversation

application: MCA4
topic: MCA4-

Any application that wants to be a client of a DDE server, must open the conversation first by specifying an
application and a topic name. The application name is MCA4 and the topic is MCA4-.

4.4.2 DDE Execute

The DDE Execute command can be used to perform any action of the MCA4 program. Any of the Control
command lines described in section 4.3 can be used. For example a sequence of control commands saved
in a file TEST.CTL can be executed by specifying the command

RUN TEST.CTL

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Fig. 4.30: Opening the DDE conversation with the MCA4 server in LabVIEW

Software Description

The MCA4 program then executes the command and, after finishing, it sends an Acknowledge message to
the DDE client. This can be used to synchronize the actions in both applications. DDE Request

The DDE Request is a message exchange to obtain the value of a specified item. Only two items are defined

for DDE request up to now: RANGE and DATA. The value is obtained as an ASCII string, i.e. it must be

converted by the client to get the numbers. All other parameters concerning the setup can be obtained by the

client application by reading and evaluating the configuration file.

RANGE

The RANGE item can be used to obtain the total number of data.

DATA

With the DATA item the data is obtained. The value of this item is a multiline string that contains in each line
a decimal number as an ASCII string.

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Fig. 4.31: Executing a MCA4 command from a LabVIEW application

Fig. 4.32: Getting the total number of spectrum data with LabVIEW

Software Description

4.4.3 Close Conversation

After finishing the DDE communication with the server program, it must be closed.

The following figure shows the “Panel” of the described VI for LabVIEW.

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Fig. 4.33: Getting the data with LabVIEW

Fig. 4.34: Closing the DDE communication in LabVIEW

Software Description

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Fig. 4.35: Control Panel of the demo VI for LabVIEW

Software Description

4.5 Controlling the MCA4 Windows Server via DLL

The MCA4 server program provides access to all functions, parameters and data via a DLL (“dynamic link
library”). So the server can be completely controlled by the MPANT software that provides all necessary
graphic displays.

The DLL DMCA4.DLL is an interface providing functions to communicate with the server program. Most of
these functions send messages to the server as you do it when operating the server program by sending
Windows messages via mouse clicks. Please do not expect any functions in this DLL for controlling the
hardware directly. All software using the DLL interface requires that the server program is running. The DLL
was mainly developed as an interface between the server program and MPANT, not as a nice developing
tool for customers. But by looking at the programming examples and some hints in the DLL documentation it
should be easy to develop own programs that are able to control the server like MPANT does.

The server program has a built-in command interpreter. The syntax of these commands is described in
chapter 4.3, and in the MPANT on-line help (look for: "How to use the command language.."). It is
recommended to send commands like "range=16384" to the server via the RunCmd DLL function, i.e.
RunCmd(0, "range=16384"); if you want to set parameters like a spectra length. The alternative method is to
store all settings parameters into the DLL by calling the DLL function StoreSettingData(setting, 0); and then
calling NewSetting(0); to send a message to the server to read new settings from the DLL. This method will
not work for changing a spectra length to avoid the problem of any undefined memory pointers. The range
parameter should be changed by the server program only (or by sending a "range=.." command). The
recommended usage of the DLL is reading parameters like Status, Settings, Strings, Cnt numbers, ROI
boundaries using the corresponding DLL functions, but for any actions or setting any parameters the
command interpreter should be used.

It is important that the DLL is loaded first by the Server program and that it is loaded from the same path by
all programs using it. Otherwise it does not work to access the shared memory. The dmca4.dll is installed by
the installation program into the standard Windows folder for 32-bit or 64-bit DLLs, respectively. Please make
sure that there is nowhere else any file dmca4.dll.

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NOTE:

The complete documented source code of the DLL including a library with fundamental VI’s and an
example VI for LabVIEW and an example Visual Basic and C program is available as an option.

MPANT Software

5 MPANT Software

The window of the MPANT program is shown here. It enables the full control of the MCA4 via the server
program to perform measurements and save data, and shows the data on-line in several windows.

The server program MCA4.EXE automatically starts MPANT. If you try to start MPANT before the server is
started, a message box warns that you should start the server first. If you want to use the server without the
MPANT display program, you may rename the file “mpant.exe” into “mympant.exe”. It will then not be found
by the server and not started. MPANT can be closed at any time without affecting the data acquisition and
can be restarted out of the server menu or by a shortcut on the desktop.

MPANT has viewing capabilities for single- and two-dimensional spectra. For ROI's the ROISum, Net sum
and the mean counts per channel (i.e. ROISum divided by number of channels) and the centroid is displayed
(<x> for single spectra, <x> and <y> for two dimensional). A single spectrum can be converted into a two­dimensional one by specifying the x dimension in the display option dialog. It is possible to drag a rectangle
and zoom into this rectangle. Rectangular ROI's can be set and the ROISum and Net ROISum is displayed.
The Net Sum is calculated the same way like in the single view, by subtracting a linear interpolated
background from the both outmost channels in x-direction. This Net sums are then summed up in y-direction.
The ROI editing dialog is changed into a Rectangular Editing dialog for MAP and ISO displays. The Cursor
can be moved in x and y direction using the mouse and the arrow keys, in ISO display only using the arrow
keys.

A status window at the left side gives all information about the status of the MCA4. Below the different
counting rates a progress bar shows the filling of the FIFO.

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Fig. 5.1: MPANT main window

MPANT Software

A toolbar provides fast access to many used functions in the menu. A status bar at the bottom gives help
about the meaning of the toolbar icons. A cursor appears when clicking the left mouse button inside the
graphics area. The cursor can be moved using the arrow keys. To get rid of the cursor, make a double click
with the right mouse button outside the graphics area. To define a region, press the right mouse button, and
while keeping the button pressed, drag a rectangle. In zoomed state a scroll bar appears that allows scrolling
through the spectrum.

In the following the several menu functions are described together with the corresponding toolbar icons.

5.1 File Menu

Load..., Add..., Save Display As..., Save MPA As...

These menu items provide the usual functions for loading and saving data, either a complete data set when
loading or saving a .MPA data file, or separated spectra when loading or adding a .MP data file. The 'Load'
function creates then a new spectrum for compare, whereas the 'Add' functions adds the data to the
spectrum selected by the active window. For saving a selected spectrum into a seperated file, click on the
respective display window and select “Save Display As..” from the MPANT File menu. If you want to have the
data file seperated from the header containing the configuration, first open the data operations dialog using
the toolbar icon showing the 4 yellow diskettes, select “Selected Spectra” and check “Seperate Header” as
shown in Fig. 4.3.When saving data, you have the choice between several formats like binary (.DAT), ASCII
(.ASC), GANAAS (.SPE), EMSA (.emsa) and CSV (.CSV) format by selecting it from “Save type As...”. To
read a CSV file with Excel, load it as a text file and configure TAB characters as seperators.

When you load data, select a header file (extension .MP). This file contains the information about the size
and format of the data file, which is then automatically read. With “Add” the data is added to the present data.

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Fig. 5.2: MPANT Map and Isometric display

MPANT Software

The data read from a file is shifted according to the calibration, if it is available and 'Use Calib' is checked in
the MCA4 Data Operations dialog, see Fig. 4.3. This dialog can also be used to load spectrum data from a
file into an existing display window.

New Display:

With the Open New menu item or the corresponding icon a new Display window can be created and shown
as the active window. In the “Open New Display” dialog box the spectrum for the new display can be
selected.

Open All

By selecting the Open All menu item, all available Displays are shown. The windows of the last opened
Display become active.

Close All

By selecting the Close All menu item, all Display windows are closed.

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Fig. 5.3: File New Display dialog

MPANT Software

Compare...

The Compare... menu item opens a dialog that enables to show two spectra with different colors in the same
window. The active display window can be checked as a primary window and there is a list of other spectrum
windows that can be inserted as secondary windows.

Using the features of the software it is possible to create a shifted spectrum that has a characteristic peak at
the same place as the primary spectrum, see 4.1.11 . This way a view as shown in Fig. 5.5 can be created.

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Fig. 5.5: Compare two spectra

Fig. 5.4: Compare dialog

MPANT Software

Print...

The Print menu item opens the print dialog. It allows to arrange several pictures on a page into zones. The
number of zones in vertical and horizontal direction can be specified. The Color can be black/white, RGB
(colored) or Gray scale. RGB is recommended also for black laser printers. Some info lines containing date,
file name and title can be added. For each page a temporary file PRINT1.WMF, PRINT2.WMF... will be
created. This file is in Windows Meta file format and can be exported into some other Windows applications.

Setup Printer...

The Setup Printer menu item enables to configure the printer.

Exit

The Exit menu item exits the MPANT program. The server and any measurement data remain active,
MPANT can be easy restarted out of the file menu of the server program.

5.2 Window Menu

The Window menu enables arranging the Display windows.

Tile

With the Tile menu item or by clicking the corresponding icon, all opened and displayed MPANT Display
windows are arranged over the full MPANT client area trying to allocate the same size for each window.

Cascade

The Cascade menu item or respective icon arranges all windows in a cascade display.

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Fig. 5.6: Print dialog

MPANT Software

Open All

By selecting the Open All menu item, all Display windows are opened.

Window list

At the end of the Window menu, all created Display windows are listed with their names, the current active
window is checked. By selecting any of the names, this window becomes the active window and is displayed
in front of all the others.

5.3 Region Menu

The Region menu contains commands for Regions and ROI's (Regions of Interest). A Region can be defined
by marking it in a display, with the mouse using the right mouse button and dragging a rectangle over the
area one is interested in. A ROI, i.e. an already defined region in a single spectrum can be shown zoomed by
double-clicking with the left mouse button on the corresponding colored area in the bar at the bottom of the
spectra display. A single mouse click with the left button on the corresponding colored area makes this to the
selected ROI and lets the counts contained in this ROI be displayed in the information lines of the respective
window. Advance the selected ROI to the next or previous one using the "+" or "-" key from the numeric
keypad.

Polygonal and curved ROI's in MAP displays are implemented in addition to the rectangular ROI's. The
boundaries can be polygonal, circular, annular or pie. Make a choice of the shape using the Menu
Region...Shape or the corresponding toolbar icon. Define the ROI using the right mouse button, the TAB and
the END key (please read the help in the status bar) and save the ROI using the toolbar icon "Create new
ROI" . Advance the selected ROI to the next or previous one using the "+" or "-" key from the numeric
keypad. The ROI boundary is displayed by lines or circles and the ROI area can in addition be displayed in
inverted color by enabling the checkbox "Invert ROI Pixel" in the MAP Display options dialog. The sum and
net sum of counts within the selected ROI is displayed. The net sum is calculated by subtracting a
background integral by summing line integrals S(y) for each y coordinate using the mean value of the counts
at the lowest and highest x coordinate of the ROI.

Zoom

The Zoom item or respective icon enlarges a Region to the maximum Spectrum Display size.

Back

The Back menu item or clicking the corresponding icon restores the last zoom view. Each time a Back
command is clicked the view is stepped back one step.

Zoom Out

The Zoom Out menu item or clicking the corresponding icon enlarges the actual zoom view by a factor 2, if
possible. You can also use a mouse wheel for zooming in at out.

Home

Clicking the Home menu item or the corresponding icon restores a Display to the basic configuration
showing the complete spectrum.

Shape

Selecting the Shape menu item opens a sub menu with the items Rectangle, X-Slice Y-Slice and Rectangle,
Polygon, Circle, Annular and Pie to choose the ROI shape.

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MPANT Software

Rectangle

Sets the region shape to a rectangle with arbitrary dimensions. To enter the rectangular region, press the
right mouse button, drag a rectangle, and release the button to define the region.

X-Slice

Sets the Region shape to the rectangle with maximal height.

Y-Slice

Sets the Region shape to the rectangle with maximal width.

Polygon

Sets the Region shape to polygonal. To enter a polygonal Region using the mouse, press the right button for
each point, the TAB key for a next polygon and the END key to close it.

Circle

Sets the Region shape to circular. To enter a circular Region using the mouse, click the right button at the
center, move the mouse and press the END key to finish.

Annular

Sets the Region shape to annular. To enter an annular Region using the mouse, click the right button at the
center and first circle and press the END key at the second circle.

Pie

Sets the Region shape to pie. To enter a pie Region using the mouse, click the right button at the center and
first radial end-point, press the END key at the second radial line end-point.

Create

The Create menu item creates a new ROI from the current marked Region.

Delete

By selecting the Delete menu item or the respective icon, the current active ROI is deleted and the previously
defined ROI is activated.

Edit...

With the Edit item, a dialog box is opened which enables editing the ROI list, i.e. create a new or delete,
change and activate an existing ROI. Also the peak values for an automatic calibration can be entered here.
A ROI can be edited and added to the list. It can also be made to the “Active ROI”, that is the special ROI
that is used by the server program to calculate the events within this ROI and look for an event preset. The
ROI list can be cleared and it can be written into a file with extension .CTL, which can be directly loaded into
the server to restore the ROI list.

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MPANT Software

Clicking on it in the ROI list can change the selected ROI. In the MPANT spectrum display the total and net
sum of the selected ROI is displayed.

ROI names are implemented. The name can be entered in the ROI editing dialog. Press "Modify" to insert a
new name from the edit field of the selected ROI into the list.

For polygonal, circular, annular and pie ROI's there is a special dialog to select and edit all the parameters.
The ROI definition parameters can be saved into a .CTL file and reloaded using the File menu like any
control file. Note that the selected ROI can be advanced in any activated spectra display by pressing the "+"
and "-" key from the numeric keypad.

X-projection, Y-Projection

Projections of ROI's in dual parameter spectra to the x- and y-axes are implemented. There are menu items
"X-Projection" and "Y-Projection" in the Region menu. They create new single spectra displays showing the
respective projection of the selected ROI in a dual parameter spectrum in the active window.

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Fig. 5.7: Slice and rectangular ROI Editing dialog

Fig. 5.8: Polygonal ROI Editing dialog

MPANT Software

Fit...

By selecting the Fit... menu item or the respective icon, a single Gaussian peak fit with linear background is
performed for the currently marked region. The fitted curve is displayed and a dialog box shows the results:

The full width at half maximum FWHM and Position of the Gaussian can be changed and a New Fit can be
performed, they even can be fixed to the entered value by marking the respective check box. The Position
and FWHM are displayed in channels and also in calibrated units, if a calibration is available. The area of the
Gaussian is also shown. For all values also the standard deviations are given. The value of Q is the
normalized chi**2. To take into account the systematic error of the line shape, you may multiply the errors
with the square root of Q. Click on Save to append a line containing the results to a Log file with the specified
name. OK closes the dialog and lets the fitted function in the display also if it is refreshed, whereas after
Cancel the curve no longer will be shown in a refreshed display. Options... opens a new dialog box to define
the information in the log file.

Peak Evaluation...

By selecting the Eval... menu item or the respective icon, a general peak evaluation with linear background is
performed for the currently marked region. The calculated background curve is displayed and a dialog box
shows the results:

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Fig. 5.9: Single Gaussian Peak Fit

MPANT Software

The Position and FWHM are displayed in channels and also in calibrated units, if a calibration is available.
The area of the peak is also shown, as well as the FWTM and FWTM / FWHM ratio. Click on Save to append
a line containing the results to a Log file with the specified name. OK closes the dialog. Options... opens a
new dialog box to define the information in the log file:

Two radio buttons enable to select between Gaussian fit and general peak evaluation. The several quantities
are written in standard text format with Tabs as separators and a Newline character at the end of each line,
so the file can be read with standard calculation programs like EXCEL as a text file. Click on Print Header to
write a header line.

Fit ROIs

With the Fit ROIs item, for all ROI's a Single Gaussian Peak Fit is performed and the results are dumped into
the log file.

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Fig. 5.11: Log file Options

Fig. 5.10: Evaluation of a non-Gaussian peak

MPANT Software

Auto Calib

Makes a Gauss fit for all ROI's in the active Display for which a calibration value was entered in the ROI
editing dialog, and performs a calibration using the fit results. You have then only to check “use calibration” in
the calibration dialog opened with to use it.

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MPANT Software

5.4 Options Menu

The Options Menu contains commands for changing display properties like scale, colors etc., hardware
settings, calibration and comments.

Colors...

The Colors menu item or respective icon opens the Colors dialog box.

It changes the palette or Display element color depending on which mode is chosen. The current color and
palette setup may be saved or a new one can be loaded.

To change on of the colors, select "Palette colors" and click on one of the colors. In the Color Palette dialog
box the RGB values can be edited or for a 256 color video driver one of the Physical palette colors can be
chosen.

Display...

The Display menu item or the corresponding icon opens for single spectra the Single view dialog box.

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Fig. 5.12: Colors dialog

Fig. 5.13: Color Palette dialog

MPANT Software

Here the graphic display mode of single spectra can be chosen. The 'Type' combo box gives a choice
between dot, histogram, spline and line. The 'Symbol' combo box gives a choice between None, Circle,
Triangle down, Triangle up, Cross, Snow-flake and Diamond. The symbols can be filled by checking Fill,
error bars can be displayed by checking Error Bar.

'Dot' means that each spectra point is shown as a small rectangle or the specified symbol, the size can be
adjusted with the size combo box. 'Histogram' is the usual display with horizontal and vertical lines, 'spline I'
means linear interpolation between the points, and 'line' means vertical lines from the ground to each spectra
point.

If the displayed spectra range contains more channels as pixel columns are available in the video graphic
display, usually only the maximum value of the channels falling into that pixel columns is displayed. But it can
also explicitly specified by marking the check boxes “Max Pixel”, “Mean Pixel” ,“Min Pixel” or “All” which
value will be displayed. It is also possible to display all three possible Pixel values in different colors that can
be chosen in the colors dialog. For the “Mean Pixel” a Threshold value can be entered; channel contents
below this value then aren't taken into account for the mean value calculation. As plotting all values costs a
lot of computing time for very large spectra, it is replaces automatically by “Max” and “Min” pixel for spectra
with more than 1 million counts.

The button labeled Custom Formula... provides spectra that are calculated in a special DLL named
FMPA3.DLL. This DLL allows to calculate spectra and to display it with the MPANT program. The source
code of this DLL is part of the optional DLL software interface, so it is possible to program customer defined
functions. Select a single spectrum and open the Display options dialog. Press then the button labeled
"Custom formula...". A dialog box "Custom-transformed spectra" is opened. Here the formula for the
calculation can be selected and the parameters can be edited. A new display window showing the calculated
spectra can be created. Error Bars can be activated in the display options dialog, for the calculation of the
error bars also the DLL is used. Formula #6 calculates a Fourier transform of a wave form acquired in scope
mode, see Fig. 2.14.

It is possible to change to a two dimensional view of the spectrum by specifying the x Dimension and clicking
the button ">> MAP" from the Single Display Options dialog.

For MAP displays the Display Options dialog is changed and enables a choice between four Graphic types:
bitmap dot, vector dot, bitmap contour and vector contour. Bitmap Dot is recommended as a standard,
because it makes a good and fast display. The check box Invert Roi Pixel changes the color inside ROI's to
make them better visible. Vector Contour paints colored contour lines. To calculate the lines takes a lot of
time and causes the mouse pointer changing to an hourglass. But it gives very impressive colored pictures
suited especially for presentation and when looking carefully at spectra details.

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Fig. 5.14: Single Display Options dialog

MPANT Software

From the MAP View dialog it is possible to change to Single view by clicking ">> Single" or change to
Isometric View by clicking ">> Isometric". This can also be done directly via the respective toolbar icon .

In isometric mode several single spectra are drawn behind each other. The Precession angle around the
vertical axis can be chosen in multiples of 90 degrees. This rotation can also be done directly using toolbar
icons and . The Tilt angle is between the x and y-axis and can be chosen between 15 and 89 degrees.
The Height specifies the percentage of the z-axis length respective to the whole drawing, it can be entered
between 0 and 99. With hidden it can be specified whether the hidden parts are not drawn. If
"Monochrome" is checked, the spectra are painted monochrome, otherwise in color.

Axis...

By the Axis... menu item or the respective icon, the Axis Parameters dialog box is opened.

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Fig. 5.15: Map Display Options dialog

Fig. 5.16: Isometric Display Options dialog

MPANT Software

It provides many choices for the axis of a display. The frame can be rectangular or L-shape, the frame
thickness can be adjusted (xWidth, yWidth). The font size can be chosen between Small and Large. A grid
for x and y can be enabled, the style can be chosen between Solid, Dash, DashDot and DashDotDot. Ticks
on each of the four frame borders can be enabled, the tick length and thickness can be chosen. The style of
the axis labeling depends on enabled ticks at the bottom respective left side: If no ticks are enabled there,
only the lowest and highest values are displayed at the axis, otherwise the ticks are labeled. 'Use calibration'
changes the axis ticks and labels into calibrated values. A check box "Start maximized" allows to define if the
MPANT main window should start in maximized size. It is necessary to save the MPANT options to make
these settings permanent.

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Fig. 5.17: Axis Parameters dialog

MPANT Software

Scaling...

The Scaling menu item or the corresponding icon opens the Scale Parameters dialog box.

It enables changing the ranges and attributes of a Spectrum axis. By setting the Auto scaling mode, the
MPANT will automatically recalculate the y-axis maximum value for the visible Spectrum region only. To keep
the same height of the visible region for a longer time, deselect the Auto scaling mode. Then with the scroll
bar thumb one can quickly change the visible region scale, otherwise the scale will be changed
automatically. The Minimum auto scale mode helps to display weak structures on a large background.

Lin / Log scale

For a Lin scale all data intervals have the same size. With Log scale the intervals will be small for small y
values and large for large y values. All options have effect only on the active Display.

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Fig. 5.18: Scale Parameters dialog

MPANT Software

Calibration...

Using the Calibration menu item or the corresponding icon opens the Calibration dialog box.

Choose between several calibration formulas. Enter some cursor positions and the corresponding values.
The actual cursor position can be entered by pressing 'Cursor' or the last fitted peak position by pressing 'Fit'.
Click on Add to insert the calibration position into the list, then on Calibrate. The obtained coefficients can be
inspected together with the statistical error, or they can be changed and entered by hand. If ‘use calibration’
is on, the calibrated values are displayed together with the channel position of the cursor. For MAP spectra
the dialog is slightly different and allows to select by two radio buttons between the calibration of x- and y­axis. For a selected parameter there is only one calibration: If any ADC is already calibrated in a single
spectrum and it is used also in a MAP spectrum, the calibration is the same here.

The fastest way to get a good calibration is to create ROI's around peaks with known energy and enter the
energy in the ROI editing dialog, see Fig. 5.7. Then use the “Auto Calib” function in the region menu. You will
immediately get a calibration and the dialog opens as shown in Fig. 5.19.

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Fig. 5.19: Calibration dialog

MPANT Software

Comments...

Up to 13 comment lines with each 60 characters can be entered using the Comments dialog box. The
content of these lines is saved in the data header file. The first line automatically contains the time and date
when a measurement was started. The second line contains the title of the spectra. Note that editing this line
changes the spectra name. This is the only method to change the name of physical ADC spectra. The
description of each comment line can be changed by editing the file COMMENT.TXT.

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Fig. 5.20: Comments dialog

MPANT Software

Hardware...

The Hardware settings dialog box allows to make all the respective settings (ref. 4.1.4 ).

Data...

The Data Operations dialog allows to edit format settings and to load and save spectra data, ref. 4.1.3 .

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Fig. 5.21: Settings dialog

Fig. 5.22: Data Operations dialog

MPANT Software

System...

The System Definition dialog box allows to make all the respective settings, see 4.1.10 .

Spectra...

The Spectra dialog box allows editing the list of calculated and dual parameter spectra, see chapter 4.1.11

Slice...

The Slice option allows to create new single spectra displays, showing a slice in a dual parameter spectrum.
Click on a dual parameter spectrum display to make it the active window, then select the Slice menu item or
toolbar icon. The Slice dialog box is displayed.

Select ”x=const” or ”y=const” for the slice direction, and the coordinate. Clicking the "create" button creates
the new display window. In the title bar of the new window the name of the dual parameter spectra and the
slice coordinate is shown.

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Fig. 5.23: System Definition dialog

Fig. 5.24: Spectra dialog

MPANT Software

The slice position can be changed using the scroll bar in the Slice dialog, or by entering the value in the edit
field and pressing the button, which is labeled ”Set” after creation of the slice view.

Clicking its close field can close the Slice dialog. Created slice spectra displays remain visible and their
coordinates can be changed later using the Slice utility again. The position of the Slice dialog with respect to
the MPANT main window can be saved in the MPANT.CFG file. Rectangular ROI's are visible in the slice
spectra display and can be created here.

Replay...

The menu item Options – Replay... opens the Replay settings dialog (ref. 4.1.3 ).

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Fig. 5.25: Slice dialog

Fig. 5.26: Replay dialog

MPANT Software

Tool Bar...

Selecting the Tool Bar Menu item opens the Tool Bar Dialog Box. It enables arranging the icons in the Tool
Bar.

If it is enabled, an array of icons in the MPANT Menu is shown. Clicking the left mouse button with the cursor
positioned on an icon, the user can perform a corresponding MPANT Menu command very quick.

It is also possible to include icons for free programmable function keys F1...F12 into the Toolbar. The function
keys can be programmed in the Function keys dialog with any one of the commands described in 4.3 . It can
be accessed either by clicking the "Function keys..." button or directly from the Options menu.

The functions can be executed by clicking the corresponding icon in the toolbar or by the corresponding
function key on the keyboard simultaneously with the CTRL key. The MPANT window must be the active on

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Fig. 5.27: Tool Bar dialog

Fig. 5.28: Function keys dialog

MPANT Software

the desktop and have the focus, i.e. it must be the top window. Uncheck the “Confirm Start” check box if you
don't like the message box asking for a confirmation before starting a new acquisition.

Status bar

With this menu item the Status bar at the bottom of the MPANT main window can be switched on or off. A
corresponding check mark shows if it is active or not. The Status bar usually shows if an acquisition is active.
When the left mouse button is pressed while the mouse cursor is within a toolbar icon, it displays a short help
message what the meaning of the toolbar icon is.

Status window

The status window at the left side of the MPANT main window can be shown in a small or large size or can
be hidden.

Save As...

Saves all parameters defined in the Options menu to the MPANT.CFG or a user defined config file.

Open...

Loads a new configuration.

5.5 Action Menus

Start

The Start toolbar button erases the data and starts a new measurement.

Halt

The Halt toolbar button stops a measurement.

Continue

The Continue toolbar button continues a measurement.

Erase

The Erase toolbar button erases the data.

If more than one systems are defined for starting and stopping combined MCAs together, more groups of
start / halt / continue / erase icons appear in the toolbar for the respective systems.

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MPANT Software

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Fig. 5.29: MPANT with four systems enabled

Programming and Software Options

6 Programming and Software Options

The MCA4A can be controlled by user-written programs using the DLL software interface with example
programs for Visual Basic, LabVIEW and C that is available as an option. Furthermore, LINUX software is
available as an option containing a driver, library and console test program. A Windows software similar to
the LINUX package that runs without the server using a stand-alone DLL is also available on demand for
customers who own one of the two available library packages.

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Appendix

7 Appendix

7.1 Absolute Maximum Ratings

Input voltage: any ADC input: ...................................................................... -16 … +17 V

any GATE / MCS input (short duration only): ...................... -1.7 ... +5.54 V

any FEATURE I/O port: ...................................................... -0.5 … +5.55 V

any Counter input: ................................................................-0.5 … +7.0 V

DC power supply: ............................................................................ +14 V

DC input current: any ADC input: .............................................................................. ±17 mA

any GATE / MCS input: ................................................................. ±70 mA

any DIGITAL I/O port: .................................................................... ±10 mA

any Counter input: ........................................................................ ±50 mA

Input power: any GATE / MCS input: ......................................................... max. 0.25 W

any Counter input (termination resistors): ............................... max. 0.5 W

7.2 Recommended Operating Conditions

Power supply: .............................................................................. nominal +12 VDC / 15 W

voltage range: ......................................................................+11 ... +14V

DC

Operating temperature range: .................................................................................................. 0 to +50°C

GO-Line load: .................................................................................... min. 1 kΩ to +5.0 V

or ................................................................................... min. 2 kΩ to GND

Digital I/O input voltage: ................................................................................................. 0 … +3.3 V

7.3 Specifications

7.3.1 ADC inputs

Input impedance: (8V, option) ................................................................................... 1.07 kΩ

(10V, standard) ............................................................................. 1.33 kΩ

Input voltage range (10V option): unipolar ....................................................................... nominal 0 … +10 V

bipolar .................................................................................. nominal ±5 V

Other ranges settable by jumpers:

8V range: unipolar ......................................................................... nominal 0 … +8 V

bipolar ................................................................................. nominal ±4 V

2.5V range: unipolar ...................................................................... nominal 0 … +2.5 V

bipolar ............................................................................ nominal ±1.25 V

2.0V range: unipolar ......................................................................... nominal 0 … +2 V

bipolar ................................................................................. nominal ±1 V

7.3.2 GATE / MCS inputs

Input impedance (selectable): (to GND) ............................................................................................ 50 Ω

(to GND or + 3.3V) .......................................................................... 4.7 kΩ

Input voltage range: positive (TTL, slow NIM) ................................ 0 … +3.3V (5 V compatible)

negative (fast NIM) ................................................................ 0 … -800mV

4 respect maximum input power limit
5 Maximum DC undershoot below GND must be limited to either -0.5V or 10mA. During transitions, undershoot to -2.0V or overshoot

to +7.0V is allowed, provided this lasts less than 10ns and with the current is limited to 200mA

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Appendix

Input threshold voltage: positive (TTL, slow NIM) .................................................................. +1.3V

negative (fast NIM) ....................................................................... -300mV

Pulse width (high, low): (MCS START and CHADV) ..................................................... min. 1.0 ns

(MCS STOP 1 and 2) ............................................................... min. 0.8 ns

Frequency: (MCS START and CHADV) ................................................ max. 100 MHz

(MCS STOP 1 and 2) ......................................................... max. 400 MHz

Slew rate requirement: ............................................................................................... min. 25 V/µs

7.3.3 SCA outputs

Output voltage (at IC pin): VOH (IOH = -4.0mA) ..................................................................... min. 2.4 V

VOL (IOL = 8.0mA) ...................................................................... max. 0.4 V

Output impedance: (series resistor) .................................................................................. 22 Ω

SCA output pulse width: ........................................................................................................ 120 ns

7.3.4 Digital I/O ports

R Pull: ( default pull-up to +3.3V) ............................................................... 1.0 kΩ

R I/O: ( default series resistor) ..................................................................... 22 Ω

Input voltage (at IC pin): VIH ............................................................................................. min. 2.0 V

VIL ............................................................................................. max. 0.8 V

Output voltage (at IC pin): VOH (IOH = -4.0mA) ..................................................................... min. 2.4 V

VOL (IOL = 8.0mA) ...................................................................... max. 0.4 V

7.3.5 Reference clock I/O

Input frequency: (auto dtected) ........................................................................ 5 ... 100 MHz

Output frequency: ....................................................................................................... 10 MHz

Impedance: ........................................................................................ (dc blocked) 50 Ω

Output HIGH voltage: (50 Ω load) ................................................................................. typ. 2.0 V

Output LOW voltage: (50 Ω load) ................................................................................. typ. 0.4 V

Input amplitude: (clipped sine or sine wave) ...................................................... typ. 3.3 V

PP

7.3.6 Octal Counter inputs

Count frequency: ............................................................................................. max. 125 MHz

Input impedance: ............................................................................................... 50 Ω / 0.5 W

Input pulse width: (high or low) ................................................................................ min. 4 ns

Input HIGH voltage: ....................................................................................................... min. 2 V

Input LOW voltage: .................................................................................................. max. 0.4 V

7.3.7 RTC RESET input

Input impedance: ............................................................................................... 50 Ω / 0.5 W

Input pulse width: (high or low) ................................................................................ min. 8 ns

Input HIGH voltage: ....................................................................................................... min. 2 V

Input LOW voltage: .................................................................................................. max. 0.4 V

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Appendix

7.4 Performance

7.4.1 General

DDR2 Memory: ................................................................................... 1Gbit = 32M x 32 bit

Memory modes: (FIFO) ......................................................................................... Listmode

Data throughput: (USB transfer rate) ........................................................................... MB/s

ADC data buffer memory: (each input) ............................................................................. 32k x 16 bit

........................................... segmentable in 1 / 2 / 4 / 8 equal sized blocks

Basic operating modes6: Pulse Height / Multichannel Analysis ................................................. PHA

Oscilloscope ................................................................................. SCOPE

Frequency Domain ............................................................................. FFT

Sampled Voltage Analysis .................................................................. SVA

Multichannel scaling .......................................................................... MCS

RTC (Real Time Clock) resolution: ........................................................................................................... 1 ms

(optional) ............................................................................................ 8 ns

Reference oscillator: Stability: ....................................................................................... ±50 ppm

Aging: .................................................................................. ±3 ppm / year

7.4.2 Analog-to-Digital Converter

Conversion time: abs. Maximum PHA ............................................................................ 8 ns

Gaussian fit PHA ........................................................ (2 x i17 + 96) x 8 ns

Flattop fit .......................................................................... (M8 + 42) x 8 ns

Live- / realtime resolution: (standard) .......................................................................................... 1 ms

(RTC option) ........................................................................................8 ns

Timer preset range: (standard) ............................................................................... < 248 x 1 ms

(RTC option) ............................................................................ < 248 x 8 ns

Reference voltage: temperature drift: ............................................................... max. 3 ppm/°C

Resolution: Gaussian fit (32k range) .......................................... typ. 1.7 … 2.8 FWHM

Integral non-linearity9: (for 97% of the channels, ref. Fig. 7.1 and Fig. 7.2) .................... < ±3.5 %

Differential non-linearity10: (Gaussian fit and 97% of the channels, ref. Fig. 7.3) ..................... < ±1 %

GATE to threshold crossing: t

setup

..................................................................................................... TBD

t

hold

...................................................................................................... TBD

TAG bits sampling period: ......................................................................................................... 2.5 µs

6 some modes may be used simultanously
7 fit is performed through (2 x i1 + 1) sample data (1 < i1 < 64)
8 M = number of samples averaged (0 < M < 256)
9 INL(n) = [COUNTS(n) / Mean(Range)] – 1, with n = 300 … 31300, Range = 31001

includes non-linearities of the ramp generator, tail pulser and shaping amplifier

10 DNL(n) = COUNTS(n) / [0.5 x COUNTS(n-1) + 0.5 x COUNTS(n+1)], with n = 300 … 31300

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