Relazione tecnica sistema di comunicazione multiprotocollo con FTDI UM232H

In this paper a system that allows a computer or an embedded system to easily communicate with devices which implement the usual standard communication protocols is proposed. The system consists of a hardware device and a software application. The hardware component is based on the FTDI FT232H chip, a single channel USB to serial/parallel port converter which can be configured in a variety of industrial standard serial or parallel interfaces. The software application manages the hardware component and provides a user friendly graphical user interface which allows the customers to choose the desired protocol, to configure some protocol and message parameters, and to communicate with their devices. Therefore, the system can be used without knowing programming languages and/or protocol characteristics

The DAQ system support to the AIV activities of the ASTRI camera proposed for the Cherenkov Telescope Array

The Cherenkov Telescope Array (CTA), the next generation ground-based observatory for very high-energy gamma rays, is being built and will be operated by an international consortium. Two arrays will be located in the northern and southern hemispheres. Each telescope array will operate different numbers and types of telescopes. The Italian National Institute for Astrophysics (INAF) is leading the ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) project in the framework of the small size class of telescopes (SST). A first goal of the ASTRI project is the realization of an end-to-end prototype in dual-mirror configuration (SST-2M). The ASTRI camera focal plane is composed of a matrix of silicon photo-multiplier sensors managed by innovative front-end and back-end electronics. The ASTRI SST2M prototype is installed in Italy at the INAF "M.G. Fracastoro" observing station located at Serra La Nave, 1735 m a.s.l. on Mount Etna, Sicily. The ASTRI Data AcQuisition (DAQ) system acquires, packet by packet, the camera data from the back-end electronics. The packets are then stored locally in one raw file as soon as they arrive. During the acquisition, the DAQ system groups the packets by data type (scientific, calibration, engineering) before processing and storing the data in FITS format. All the files are then transferred to the on-site archive. In addition, we implemented a quick-look component the allows the operator to display the camera data during the acquisition. A graphical user interface enables the operator to configure, monitor and control the DAQ software. Furthermore, we implemented the control panel algorithms within the framework of the Alma Common Software, in order to integrate the DAQ software within the ASTRI control software. The ASTRI DAQ system supports the camera AIV activities and operations. We provide the instrument workstation to support the AIV activities in the laboratory, and the camera server on-site. In this paper, we assess the ASTRI DAQ system as it has performed the AIV tasks for the ASTRI SST-2M prototype

The software architecture of the camera for the ASTRI SST-2M prototype for the Cherenkov Telescope Array

The purpose of this contribution is to present the current status of the software architecture of the ASTRI SST-2M Cherenkov Camera. The ASTRI SST-2M telescope is an end-to-end prototype for the Small Size Telescope of the Cherenkov Telescope Array. The ASTRI camera is an innovative instrument based on SiPM detectors and has several internal hardware components. In this contribution we will give a brief description of the hardware components of the camera of the ASTRI SST-2M prototype and of their interconnections. Then we will present the outcome of the software architectural design process that we carried out in order to identify the main structural components of the camera software system and the relationships among them. We will analyze the architectural model that describes how the camera software is organized as a set of communicating blocks. Finally, we will show where these blocks are deployed in the hardware components and how they interact. We will describe in some detail, the physical communication ports and external ancillary devices management, the high precision time-tag management, the fast data collection and the fast data exchange between different camera subsystems, and the interfacing with the external systems

The Camera Server of the ASTRI SST-2M Telescopes Proposed for the Cherenkov Telescope Array

The Cherenkov Telescope Array (CTA) project is an international initiative to build the next generation of ground-based very high energy gamma-ray instrument . Three classes of telescopes with different mirror size will cover the full energy range from tens of GeV up to hundreds of TeV. The full sky coverage will be assured by two arrays, with one site located in each of the northern and southern hemispheres. In the current design scenario, the southern hemisphere array of CTA will include seventy small size telescopes (SST, 4m diameter) covering the highest energy region. Their implementation includes proposed intermediate steps with the development of mini-arrays of telescope precursors like the ASTRI mini-array, led by the Italian National Institute for Astrophysics (INAF) in synergy with the Universidade de Sao Paulo (Brazil) and the North-West University (South Africa). The ASTRI mini-array will be composed of nine telescope units (ASTRI SST-2M) based on double-mirror configuration whose end-to-end prototype has been installed on Mt. Etna (Italy) and is currently undergoing engineering tests. In the ASTRI SST-2M prototype, operating in single telescope configuration, the basic camera server software is being deployed and tested; it acquires the data sent by the camera back end electronics as a continuous stream of packets. In near real time, the bulk data of a given run are stored in one raw file. In parallel they are sorted by data type, converted to FITS format and stored in one file for data type. Upon closure, each file is transferred to the on-site archive. In addition, the quick look component allows the operator to display the camera data during the acquisition. This contribution presents how the camera server software of the prototype is being upgraded in order to fulfil the mini-array requirements, where it will be deployed on the camera server of each ASTRI SST-2M telescope. Particular emphasis will be devoted to the most challenging requirements that are related to the stereoscopy, when two or more telescopes have triggered simultaneously. To handle stereoscopy, each camera server has also to: (i) get the timestamp information from the clock distribution and trigger time stamping system, and associate it to the related camera event; (ii) get from the software array trigger the timestamp which passed the stereo trigger criteria; and (iii) forward to the array data acquisition system the stereo trigger events, according to the required data format and communication protocol

Software design of the ASTRI camera server proposed for the Cherenkov Telescope Array

The Italian National Institute for Astrophysics (INAF) is leading the ASTRI project within the ambitious Cherenkov Telescope Array (CTA), the next generation of ground-based observatories for very high energy gamma-ray astronomy. In the framework of the small sized telescopes (SST), a first goal of the ASTRI project is the realization of an end-to-end prototype in dual-mirror configuration (2M) with the camera composed of a matrix of Silicon photo-multiplier sensors managed by innovative front-end and back-end electronics. The prototype, named ASTRI SST-2M, is installed in Italy at the INAF "M.G. Fracastoro" observing station located at Serra La Nave, 1735 m a.s.l. on Mount Etna, Sicily. As a second step, the ASTRI project is focused on the implementation of a mini-array composed at least of nine ASTRI telescopes and proposed to be placed at the CTA southern site. This paper outlines the design of the camera server software that will be installed on the ASTRI mini-array. The software is based on the version installed on the ASTRI SST-2M prototype operating in a single telescope configuration. The migration from single telescope to mini-array context has required additional interfaces in order to guarantee high interoperability with other software and hardware components. In the mini-array configuration each camera communicates with its own camera server via a dedicated high rate data link. The primary goal of the camera server is to acquire the bulk data, packet by packet, without any data loss and to timestamp each packet very precisely. During array operation, the camera server receives from the SoftWare Array Trigger (SWAT) the list of science events that participate in stereo triggered events. These science events, and all others that are flagged either by the camera as interleaved calibration or by the camera server as possible single-muon events, are sent to the Array DAQ. All remaining science events will be discarded. A suitable buffer is provided to perform this processing on all the incoming event packets. The camera server provides interfaces to the array control software to allow for monitoring and control during array operations. In this paper we present the design of the camera server software with particular emphasis on the external interfaces. In addition, we report the results of the first integration activities and performance tests. <P /

An ASIC front-end for fluorescence and Cherenkov light detection with SiPM for space and ground applications

This version was subsequently modified, so that the final article is radically changed with respect to itAstroparticle and High Energy Astrophysics space missions measuring extensive air showers produced by cosmic rays and neutrinos in atmosphere require detection of very faint and intense ultraviolet and visible light. Characteristics of the new generation of SiPM (Silicon PhotoMultiplier) are potentially right for this purpose. The capability to operate SiPM contemporarily in photon counting and in charge integration is strictly dependent indeed by the design of the front-end electronics (FEE). In this context, the challenge is to find the right balance and a feasible solution for managing SiPM with a FEE to be able to work, contemporarily and efficiently, in photon counting and charge integration. In this manuscript we present a new ASIC, named RADIOROC, that is an improvement of the CITIROC and that is at the end of its design phase: this chip will be able to work contemporarily in both the named modes. The RADIOROC characteristics and the first simulations carried out on the chip design will be presented

Software design and code generation for the engineering graphical user interface of the ASTRI SST-2M prototype for the Cherenkov Telescope Array

ASTRI is an on-going project developed in the framework of the Cherenkov Telescope Array (CTA). An end- to-end prototype of a dual-mirror small-size telescope (SST-2M) has been installed at the INAF observing station on Mt. Etna, Italy. The next step is the development of the ASTRI mini-array composed of nine ASTRI SST-2M telescopes proposed to be installed at the CTA southern site. The ASTRI mini-array is a collaborative and international effort carried on by Italy, Brazil and South-Africa and led by the Italian National Institute of Astrophysics, INAF. To control the ASTRI telescopes, a specific ASTRI Mini-Array Software System (MASS) was designed using a scalable and distributed architecture to monitor all the hardware devices for the telescopes. Using code generation we built automatically from the ASTRI Interface Control Documents a set of communication libraries and extensive Graphical User Interfaces that provide full access to the capabilities offered by the telescope hardware subsystems for testing and maintenance. Leveraging these generated libraries and components we then implemented a human designed, integrated, Engineering GUI for MASS to perform the verification of the whole prototype and test shared services such as the alarms, configurations, control systems, and scientific on-line outcomes. In our experience the use of code generation dramatically reduced the amount of effort in development, integration and testing of the more basic software components and resulted in a fast software release life cycle. This approach could be valuable for the whole CTA project, characterized by a large diversity of hardware components

Temperature characterization of the CITIROC front-end chip of the ASTRI SST-2M Cherenkov camera

The Cherenkov Imaging Telescope Integrated Read Out Chip, CITIROC, is the front-end chip of the camera for the ASTRI SST-2M, one of the prototypes for the small sized telescopes of the Cherenkov Telescope Array, CTA. The telescope, operating in the energy range from a few TeV to beyond 300 TeV, is characterized by innovative technological solutions. The optical system is arranged in a dual-mirror configuration and the focal plane camera consists of a matrix of multi-pixel Silicon Photo-Multipliers. Among others, one of the most important project issue consists in the thermal characterization of the camera that, in the ASTRI SST-2M prototype, is thermo-controlled in a narrow temperature range. A set of at least nine similar telescopes will form the ASTRI mini-array proposed to be installed at the CTA southern site. In the cameras of the ASTRI mini-array telescopes the thermal control could be relaxed with a considerable gain in terms of power consumption, cost and simplicity. So, a study of the temperature dependence of the camera components is needed. The present work addresses this issue showing the results of the measurements carried out on CITIROC as a function of the temperature. We focused our investigation on the pedestal stability, linearity of the charge output signal, preamplifier gain and trigger uniformity in the temperature range 15-30°C. Our results show, for each of the above-mentioned measurable quantities, that temperature dependency is at the level of a few percent

The Online Observation Quality System for the ASTRI Mini-Array

The ASTRI Mini-Array is an international collaboration led by the Italian National Institute for Astrophysics (INAF), aiming to construct and operate an array of nine Imaging Atmospheric Cherenkov Telescopes (IACTs) to study gamma-ray sources at very high energy (TeV) and to perform stellar intensity interferometry observations. This contribution describes the design and the technologies used by the ASTRI team to implement the Online Observation Quality System (OOQS). The main objective of the OOQS is to perform data quality analyses in real-time during Cherenkov and intensity interferometry observations to provide feedback to both the Central Control System and the Operator. The OOQS performs the analysis of key data quality parameters and can generate alarms to other sub-systems for a fast reaction to solve critical conditions. The results from the data quality analyses are saved into the Quality Archive for further investigations. The Operator can visualise the OOQS results through the Operator Human Machine Interface as soon as they are produced. The main challenge addressed by the OOQS design is to perform online data quality checks on the data streams produced by nine telescopes, acquired by the Array Data Acquisition System and forwarded to the OOQS. In the current OOQS design, the Redis in-memory database manages the data throughput generated by the telescopes, and the Slurm workload scheduler executes in parallel the high number of data quality analyses.Comment: 8 pages, 3 figures, Proceedings of the 37th International Cosmic Ray Conference (ICRC 2021), Berlin, German

Procedures for the relative calibration of the SiPM gain on ASTRI SST-2M camera

ASTRI SST-2M is one of the prototypes of the small size class of telescopes proposed for the Cherenkov Telescope Array. Its optical design is based on a dual-mirror Schwarzschild-Couder configuration, and the camera is composed by a matrix of monolithic multipixel silicon photomultipliers managed by ad-hoc tailored front-end electronics. This paper describes the procedures for the gain calibration on the ASTRI SST-2M. Since the SiPM gain depends on the operative voltage and the temperature, we adjust the operative voltages for all sensors to have equal gains at a reference temperature. We then correct gain variations caused by temperature changes by adjusting the operating voltage of each sensor. For that purpose the SiPM gain dependence on operating voltage and on temperature have been measured. In addition, we present the calibration procedures and the results of the experimental measurements to evaluate, for each pixel, the parameters necessary to make the trigger uniform over the whole focal plane