Creation of a software and hardware product of a real-time system for collecting, accounting and managing data transmission of an intelligent transport system in context of the IoT

Some aspects of the functioning of modern microcontrollers of the Internet of Things in conditions that are close to real-time systems are reviewed in the article. Attention is paid to the aspects of the theory of physical data transmission, the significance of the delay metrics in the data transmission path is substantiated and emphasized. These delays (in view of the generalization of measurement results) determine the control accuracy and controllability of the data processing system as a whole, and also affect the reliability of the results. The process of formalization of the architectural template of a data collecting and accounting system for a control device (which is widespread in intelligent transport systems and the Internet of things) is described. The practical application of the approach in synchronous control through the implementation of a web interface and a control language in a microprocessor system (which can be possible at low traffic transmission rates) is substantiated. In conclusion, a generalization of the scope of application of the developed specialized computer system in transport field is given.

• to develop a specialized computer system for a wireless gateway for an intelligent transport network; • to implement support for the control language, which allows making decisions about control strategies based on current conditions and allows you streamline ESP control in accordance with the needs for some actions, in other words to provide support for adaptive control; • to ensure the collection of data on the controlled operational process and visualize it in the form of graphic means; • to formalize the process control model based on the collected data and rules (criteria), the implementation of which ensures the greatest efficiency and safety.
Thus, the subject of research is a cybernetic system with the functions of selection of information about technological processes and provision of a convenient human-machine interface with an operator, while maintaining the history of the process and implementing automatic control of the process through various information and communication means.

Aspects of functioning of microprocessor systems in systems close to real time, the importance of jitter minimization
Data collection and accounting systems in the IoT are a new direction of automation of production processes and production based on computer technology and specialized software, adapted to the technical features of inexpensive single-chip systems -which are well suited for ensuring the process of collection of information from remote points (objects) for processing, analysis and possible management of remote objects through various web interfaces.
The novelty of the studied topic is explained by the fact that earlier such systems were used exclusively in bulky control systems for automated operational processes. High requirements for hardware content were imposed to such system. Even solutions of industrial Internet of Things (which is a formal model for the development of smart control systems, taking into account the principles of Indutry 4.0) dose not propose it. It is something that shall be covered in more details due to the multi-criteria assessment of the role of the hardware component in context of real-time control systems from the point of the information transmission medium [1].
Studies that touch upon the study of the development of hardware requirements for the implementation of functionally significant components of transmitting modules of cyber-physical systems in most microprocessor-based systems are reduced to determination of temporary connection failures and determination of collisions mediated through time-measured terms such as ping and jitter. In other words through delay variations, such as the most significant (but not the only) categorical requirements that determine the fundamental aspect of the telematic interaction path (see figure 1).

Figure 1. Jitter -characteristics and types for digital transmitters.
Since the communication channels for modern dispatching systems that are very diverse, the choice of a specific traffic management solution depends on the system architecture, the distance between the dispatching unit (MTU) and the RTU (remote workplace), the number of controlled points, they express the bandwidth requirements and reliability of channels, as well as the availability of commercial communication lines.
The trend in the development of traffic management systems as a structural component of SCADA systems can be considered as use not only through the analysis of dedicated communication channels, but also corporate computer networks and specialized industrial networks (industrial buses -CAN, etc.). In modern industrial, electrical and transport systems, industrial networks have gained great popularity -specialized high-speed communication channels that effectively solve the problem of reliability and noise immunity of connections to different hierarchical levels of automation.
Based on the categorical apparatus of the requirements for the SCS being developed, we will rely on the construction of a data model that would directly relate to the aspects (requirements for functioning) of SCADA systems built on various kinds of time specifiers (see figure 2). Based on figure 2, it becomes obvious that it is necessary to develop an architectural solution that implies a minimum (adequately) available data transmission rate to achieve minimum values of time delays, and as a consequence, a decrease in the curve of loss of packages with data in real-time systems within the framework of the IoT concept.
The best jitter performance was demonstrated in the exchamge pathway by IEEE 802.11 (Supportive Technology for Information Exchange) for packages with a total rate of 2 Kbps (0.014 ms for a 30 minute session). For certain reasons these values are undoubtedly insufficient (although there is a tendency to use LoRaWAN as a reference technology for information transfer), for full-fledged data collection systems, however, they suggest earlier assumptions regarding finding the minimum available and adequate values for the requirements to compliance with the rules for the functioning of real-time systems [2].
To implement the operation of the software and hardware platform and architectural solution, an ESP8266 (ESP-12F) microprocessor module operating in IEEE 802.11n has been selected. This module has the ability to operate in the telematic mode at 9600 baud /s, which is equal to 7.68 kb/s.

Master data in software and hardware system and data management tool for a developed specialized computer system
The attractiveness of maintaining a low bandwidth for the developed analytical platform is due to the fact that existing solutions (microprocessor systems) for the Internet of Things, firstly, cannot provide a high rate of operation of integrated transceivers, and secondly, they are aimed at use in conditions of low consumption [3]. The designed developed system had requirements for working through a web interface, via HTTP, and implementing an API for remote and local management.
The database has been implemented through the master data templates (MDM), which are widely used in business systems and intelligent transport systems.  [4].
The purpose of master data management is to make sure that there is no incomplete and inconsistent data in real time by simplifying the data transmission system in the external loop (it is necessary to store all data in the device memory, and transfer only those that are necessary for exchange session (separate metrics for specific (set by the operator remotely) scales from peripheral devices): sensors and actuators, which simplifies the use of a specialized computer system in various fields of activity and informatization facilities.
The Master Data Management template (figure 3) on the one hand shall provide customization for working with data on a specific object, and on the other hand shall be independent from the specifics of the application industry, the scope of the product built on its basis and its information environment [5]. The SCADA software developed by IDEArduino is based on the C language for the ESP-12F, which has an IEEE 802.11 module.
The control language of the collection and dispatching system is implemented both through a direct control interface and a web server implemented via HTTP, as well as through an AT construct formalized through the BS-88 control language, which is defined by the ISA-88 standard. One control command takes 512 bytes of traffic.
The current edition of the control standard includes the necessary organizational and technical standards used in SCADA systems:  The control is based on the regulation of the discrete (D) and analogue (A) ports, the reading itself is realized through hardware interrupts.
The developed SCADA integrates a full-fledged automated control through an integrated approach to the definition of master data and flow control of discrete Input /Output lines in the configuration mode ("SETUP)" (see figure 4). Let's turn on $ D3 for 45 seconds using the syntax of the control language (in order to do it the designated input must be set to a positive one): 7: $D3 = 1; if ($ timer> = 45) trans {8}; // On this line, the algorithm seems to 'get stuck' (go into a controlled interrupt) until the condition is met 8: $D3 = 0; Such control structure is not like a usual device programming language, where one statement is executed at each step [6]. Note: the system provides one more statement -the "stop" statement, which stops the execution of the script. However, in this case, the AUTO field will remain enabled on the panel.
Special variables (functions) One such variable -$ timer, has been reviewed but there are others. $ntime -[n] ow [time] -current time; used as a floating point number 13.4 means 13 hours and 40 minutes $random -random number [0: 1] (used to simulate life in an empty house) $morning -start of the day for mid-latitudes (used to turn off the lights) $evening -sunset time (used to turn on the lights) $retro -timer value that timer has reached in the previous phase $temp -current temperature value from ds18b20 temperature sensor connected to D5 $ptime -time in seconds from the beginning of the scan period, equal to T_scan.