Martin Killenberg

Drivers and software for MicroTCA.4

The MicroTCA.4 crate standard provides a powerful electronic platform for digital and analog signal processing. The crate standard is highly configurable and due to an excellent hardware modularity rapid adaption to various different applications is possible. Besides the hardware modularity, it is the software reliability and flexibility as well as the easy integration into existing software infrastructures that will drive the widespread adoption of the new standard.

Real time control of RF fields using a MicroTCA.4 based LLRF system at FLASH

The Free Electron Laser in Hamburg (FLASH) is a large scale user facility, providing highly stable and brilliant laser pulses down to a wavelength of 4.1 nm. Essential for stable and reproducible photon beam is the precision control of the electron bunch parameters. The acceleration principle of the electron bunches at FLASH is based on superconducting RF technology (SRF), in which the RF fields are controlled by a digital low level RF (LLRF) system. This system has been recently upgraded to the Micro Telecommunication Computing Architecture (MicroTCA.4) to improve the performance of the field regulation. This paper presents the first measurements and operation experiences using this new electronic crate standard at a large scale research facility. RF field regulation is carried out by real time fast digital processing on several boards in a MicroTCA.4 crate, and slow automation routines running on a dual core i7 front-end CPU. Scalability and modularity of this system is one of the key parameters to meet the next steps, namely being the platform standard for the European X-ray free electron laser currently build at DESY.

MicroTCA.4-based LLRF For CW Operation at ELBE - Status and Outlook

The superconducting linear accelerator ELBE at Helmholtz-Zentrum Dresden-Rossendorf is operated in continuous wave (CW) operation [1]. The analogue LLRF (low level radio frequency) system, used since 2001, is going to be replaced by a digital solution based on MicroTCA.4. The new system enables a higher flexibility, better performance and more advanced diagnostics. The contribution shows the performance of the system at ELBE, the hardware and the software structure. Further it will summarize the last steps to bring it into full user operation and give an outlook to the envisioned beam-based feedback system that will take advantage of the capabilities of the digital LLRF system. SYSTEM STRUCTURE Hardware The ELBE injector uses a thermionic gun followed by two normal conducting (NRF) buncher cavities operating at 260 MHz and 1.3 GHz. The main accelerator consists of two cryo-modules, each is equipped with two TESLAtype superconducting cavities (SRF) that are operated routinely in CW mode. For high bunch charge and high current beams with good beam properties a superconducting photo gun is currently being developed. It contains a 3.5-cell structure operating at 1.3 GHz [2]. Figure 1: Digital LLRF schematic. In Figure 1 the main components and the associated hardware are shown. The digital LLRF system at ELBE is based on a modular system using MicroTCA.4 compatible hardware [3]. The standard separates the analogue circuits from the digital data processing. This allows an adaption of the analogue frontend to the desired application, while the digital part remains the same. For all cavities a SIS8300-L2 digitizer board is used which contains fast analogue-to-digital converters (ADCs) and a powerful Virtex 6 field programmable gate array (FPGA). For the 260 MHz buncher cavity a direct sampling scheme is applied using the DS8VM1 analogue board [4]. For all 1.3 GHz cavities a mixer configuration with DWC8VM1 has been realized [5]. The cavity pickup signals are mixed with a local oscillator (LO) to an intermediate frequency (IF) which is sampled by the ADC sitting on the SIS8300-L2 [6]. The data processing and control loop is done inside the FPGA which allows parallel execution of processes with high data rate. Software All digitizer boards are connected to a CPU-board through a PCIe link. Status information and data traces are provided to a server application while this sets all the controller parameters and offers high level features. For the first test phase a stand-alone DOOCS server application was used to control the system. It could only be accessed by remote login on to the MicroTCA.4-CPU and had no interface to the ELBE control system which is a network of programmable logic controllers (PLCs) and the graphical user interface (GUI) provided by a WinCC server-client system. In order to overcome these limitations a new server application has been developed using the ChimeraTK framework [7]. This universal toolkit allows development of applications for different control systems like DOOCS and EPICS or the OPC-UA protocol. ChimeraTK enables collaboration and joint software development of institution that are using different control system architectures. OPC-UA is a powerful protocol for industrial automation and is supported by many commercial suppliers [8]. The features integrated in the ChimeraTK framework are based on the open source implementation open62541 [9] that has been designed to run on different operating systems and hardware platforms. ____________________________________________ † m.kuntzsch@hzdr.de 6th International Beam Instrumentation Conference IBIC2017, Grand Rapids, MI, USA JACoW Publishing ISBN: 978-3-95450-192-2 doi:10.18429/JACoW-IBIC2017-MOPWC02 2 Overview and Commissioning MOPWC02 101 Co nt en tf ro m th is w or k m ay be us ed un de rt he te rm so ft he CC BY 3. 0 lic en ce (© 20 18 ). A ny di str ib ut io n of th is w or k m us tm ai nt ai n at tri bu tio n to th e au th or (s ), tit le of th e w or k, pu bl ish er ,a nd D O I.

Design and implementation of LLRF station software suite in Distributed Control System used in E-XFEL

The European XFEL project is a free electron linear particle accelerator located in Hamburg, Germany, currently being developed by DESY and to be launched later this year. The particle accelerator is controlled by RF control system, built as a chain of RF stations bound to cryomodules across the tunnel. Each RF station has a set of additional devices, that are used to control particular parts of the system. The core library for device module handling was designed using Distributed Objected Oriented Control System (DOOCS) framework as a base, and then it was extended by implementing component software pattern design, thus allowing simplified and universal way of handling communication with the hardware, as well as handling other tasks such as data validation and application logic. The library is implemented by using modern C++11/14 standards and utilizing Boost library features where necessary. The server applications utilize the library to provide common device access by using Chimera Tool Kit, as well as other register-based protocols like Simple Network Management Protocol (SNMP). In addition to the core library, two device-specific libraries were created to provide the flexibility of embedding them into third party DOOCS server applications if needed.

Software tests and timulations for real-time applications based on virtual time

Unit and integration tests are powerful tools to ensure software quality. Writing such tests for real-time applications accessing hardware requires not only replacing the real hardware with a virtual implementation in software. Also time must be controlled precisely. For a number of reasons the time scale in the simulated environment should not be identical to the real time: computations needed for a complex plant model might just be too slow for a real time simulation, or some long-term software behaviour should be tested in a short-running test. Communications with devices often require a specific timing which should be subject of a unit test. These examples demand using a virtual time scale in software tests. We present the VirtualLab framework as part of the MTCA4U tool kit. It has been designed to help implementing such tests by introducing the concept of virtual time and combining it with an implementation basis for virtual devices and plant models. The framework is designed modularly so that virtual devices and model components can be reused to test different parts of the control system software.