LPC83x microcontrollers integrate up to 32 KB FLASH and 4 KB SRAM memory.

Peripheral set includes cyclic redundancy check (CRC) module, one I 2 C bus interface, one USART, up to two serial SPI interfaces, multi-band timer, system wake-up timer, SCT timer/PWM module, direct memory access (DMA) controller , 12-bit ADC, configurable I/O ports using a matrix switch, an input signal structure comparison module and up to 29 general purpose I/O lines.

NXP introduces the LPC5411x family of microcontrollers based on the ARM® Cortex®-M4F core with an optional integrated Cortex®-M0+ coprocessor. The devices support flexible modes of power consumption and operation of peripheral nodes, providing minimal current consumption in active mode up to 80 μA/MHz.

The new microcontrollers feature increased internal RAM memory up to 192 KB, a digital dual-channel microphone interface (DMIC) and a full-speed USB interface that operates without an external clock source. The DMIC subsystem provides industry-leading power efficiency for voice recognition and voice triggering at 50 µA or less. The LPC5411x family is supported by a comprehensive set of development tools, from the LPCOpen system driver library and sample applications to integrated application development environments (IDEs) such as IAR, Keil and LPCXpresso.

As the senior member of the XMC4000 family, the XMC4800 series devices are the industry's first highly integrated ARM® Cortex®-M microcontrollers equipped with an EtherCAT® interface providing real-time communication capabilities via the Ethernet protocol. Combining the functions of a digital signal processor and a 32-bit microcontroller, the XMC4000 family is ideal for industrial applications such as digital power conversion systems, electric drives, measurement and control systems, data input/output modules, and more.

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Introduction

1. Feasibility study of the project

2. Levels of control

3. Human-machine interface

Conclusion

Bibliography

Introduction

IN given time There is a trend in the economy in which it plays one of the leading roles in managing the production of products and its next sale. In developed countries, quality management at an enterprise attracts special attention to all subsections that affect the quality of products that are manufactured. For better interaction and more effective results, enterprises are developing different approaches to quality management.

The use of microcontrollers in products for industrial and cultural purposes not only leads to an increase in the technical and economic indicators of products (cost, reliability, power consumption, overall dimensions) and makes it possible to significantly reduce development time and delay the obsolescence of products, but also gives them fundamentally new consumer qualities such as expanded functionality, modifiability, adaptability, etc.

Product quality (including novelty, technical level, absence of defects in execution, reliability in operation) is one of the most important means of competition, gaining and maintaining positions in the market. Therefore, companies pay special attention to ensuring high quality products, establishing control at all stages of the production process, starting with quality control of the raw materials used and ending with determining the conformity of the released product technical specifications and parameters not only in the gait of its tests, but also in operation, and for complex types of equipment - with the provision of a certain warranty period after installation of the equipment at the customer’s enterprise. Therefore, product quality management has become a fundamental part of the production process and is aimed not so much at identifying defects or defects in finished products, but at checking the quality of the product during its manufacturing process.

Nowadays, for the economic and social development of the country, it is necessary to radically accelerate scientific and technological progress based on the widespread introduction of new equipment and technology, comprehensive automation and automation of production and technological processes, increasing productivity, increasing the technical level and quality of products. At the present stage of development of society, solving the assigned problems is impossible without the introduction of microprocessor technology in all areas National economy countries. The use of microprocessor technology provides an important increase in work productivity, improvement of the technical level and quality of products, and savings in raw materials.

The use of microelectronic means in products for industrial, cultural and household purposes not only leads to an increase in the technical and economic indicators of products (cost, reliability, power consumption, overall dimensions) and allows one to significantly reduce development time and delay the period of “obsolescence” of products, but also provides They have fundamentally new consumer qualities (extended functionality, modification, adaptability, etc.).

1. Feasibility study of the project

In recent years, microelectronics has developed rapidly in the direction associated with the production of microcontrollers, which are designed to “intellectualize” equipment for various purposes. The use of microcontrollers in control systems ensures the achievement of exceptionally high efficiency indicators. Particularly popular are the 16-bit microcontrollers MCS-96 from Intel, which have found application in industry, the automotive industry, medicine, and household appliances for a wide variety of purposes. Their architecture is optimized for real-time event management systems. For example, the MCS-96 family provides analog-to-digital conversion, pulse-width modulation and high-speed input and output of information.

The work of modern enterprises and processing plants involves performing many complex operations. For precise control of equipment and production processes, the latest sensors, electromechanical components and servos are used.

As an example of the attractiveness of using high-tech methods to achieve precision control, consider networked automation of a production floor and connecting it to IT networks to obtain the necessary business information and strategy, on the basis of which specific production management decisions are made.

This centralized, communications-centric view of industrial control problems gives maintenance teams and industrial engineers access to data warehouses for detailed analysis and process optimization. Plant managers and facility managers can gain comprehensive insight into overall production performance by literally just glancing at a dashboard displaying process parameters.

Subsequently, processes can be controlled manually and each production cell is controlled independently of the others. Having access to summary information about the overall actual functioning of the enterprise in real time, its management is able to analyze daily production indicators to adjust the business strategy based on quickly received data.

The gradual transition from nodes of the production chain isolated from each other to network interaction took place over several years. Due to the fact that this transition was largely narrowly focused and unplanned, when each current development of the next node of an industrial control system was based on its own set of buses, networks and controllers for this project, which made this node isolated from the general industrial control system.

Despite the fact that at the moment there is a unified top-down vision of the problems of network industrial control, the view of these problems in the bottom-up direction, from the side of the central processing unit of each segment, is highly fragmented. Before today it was simply impossible to choose a single processor architecture that would work effectively at all levels of the control infrastructure.

Modern developments in the field of processor technologies provide developers with the opportunity to innovate within the framework of using a single concept in the implementation of industrial control systems. By carefully analyzing the performance, functionality and communication requirements at each control level, the designer can settle on a standard single-core processor architecture, which not only provides an optimal solution at a competitive cost, but also reduces development costs and significantly reduces design cycle time and the ability to reuse already developed software.

2. Levels of Management

Typically, a production process management system is presented as a hierarchy consisting of four levels

· Sensors and actuators used to monitor production processes by providing reports on current status and recording state changes;

· Electric motors and other systems, such as inductive heaters for influencing the state of a process or operation;

Controls that analyze information received from sensor nodes and issue commands to the actuator system to achieve the desired changes, including programmable logic controller (PLC) networks and programmable automation controller (PAC) networks , connecting devices;

· Human-machine interface modules (HMI, Human-Machine Interface), providing visual and algorithmic representation of the current state of production for engineers and technical services.

Rice. 1. Automated production, consisting of four main levels of process control

Until now, no software-compatible processor architecture has been able to cost-effectively cover all four levels of the industrial control model. By leveraging a common processor architecture, developers can reduce the number of development tools they purchase, have the ability to always work in an extremely familiar development environment, and can reuse written code.

The ARM® architecture is an open, freely licensed architecture with no proprietary rights required. The advantage of openness has made the ARM architecture a de facto standard, favoring the development of reliable, diverse, and comprehensive systems using third-party software and hardware. microcontroller network control

As a leader in embedded processors, ARM Ltd. offers a wide range of microprocessor cores to meet the performance requirements of all levels of industrial control. The evolutionary kernel strategy has won awards for software compatibility and architectural continuity. Full software compatibility when migrating from Cortex™-M3 microcontrollers to Cortex-A8 microprocessors allows for simple control system development with communication algorithms designed and tested just once, but now with the ability to choose from a full range of performance characteristics. It should be noted that some ARM cores have integrated support for industrial control functions, including deterministic modes and multitasking.

While these cores alone are a great starting point, microcontrollers and microprocessors with ARM architecture must also provide appropriate combinations of integrated peripherals and memory options. The ever-growing trend in the number of applications for industrial control tasks dictates the need to produce a large number of families, the use of which could cover the full range of possible solutions that meet the requirements for cost, performance and functionality.

Finally, to help developers create industrial control systems within a unified architectural concept, professional software debugging tools are primarily needed to facilitate the development process and provide maximum opportunities for code reuse.

The best way to illustrate the flexibility and diversity of ARM products and determine the best combination of microcontroller and microprocessor peripheral sets to implement discrete control functions is to analyze the requirements at each level of the hierarchical control model presented in Fig. 1.

The control level of production equipment is usually a large number of programmable logic controllers (PLC, Programmable Logic Controller) operating within it. Programmable logic controllers receive information from sensors and, using it, make decisions about changing the progress of the production process, and also control relays, motors or other mechanical technological devices. They can monitor and manage large arrays of I/O lines across hundreds of network nodes.

Controllers typically must operate in a deterministic mode, meaning that each I/O port takes a specific amount of time (or number of computation cycles) to respond. Where the requirements for deterministic real-time execution are not as stringent, some programmable controllers use real-time operating systems (RTOS, Real-Time Operating System), which facilitates application programming for a specific task, but assumes that the system responds through which - a separate period of time.

One of the distinctive characteristics of the ARM Cortex-M3 core is its hardware support for deterministic operation. Instead of fetching data from the cache, the Cortex-M3 core receives instructions and data directly from the internal Flash memory. This provides a hardware-based way to preserve processor state while handling exceptions. When an external interrupt signal is received, transferring control to its handler takes only 12 cycles, and in the case of nested interrupts, transferring control to the handler takes only six cycles.

From a design perspective, the determinism built into the Cortex-M3 core makes it possible to replace a two-chip motor control solution with a single-chip solution based on a single microcontroller. The dual-chip solution requires a DSP processor to control the motor tied to the network node, while constant communication with the system is maintained by the microcontroller. The use of a microcontroller with a Cortex-M3 core is a single-chip solution to both problems simultaneously.

Hardware support for deterministic operation is most effective when using network protocols specially designed for these operating modes. The IEEE1588 Precision Time Protocol (PTP) is suitable for this, the main feature of which is the accuracy of the supported time intervals and the ability to implement multi-addressing modes. From a development automation perspective, this means that a 10/100 Ethernet module supporting IEEE1588 PTP mode is an important peripheral node. Some of the highest level Programmable Automation Controllers (PACs) require support for Gigabit Ethernet, which is obvious due to the increase in data flows.

Another popular method of networking industrial automation devices is the use of CAN (Controller Area Network) protocols, which makes it possible to create distributed and redundant systems.

Wireless networks have become popular for networking programmable logic controllers, sensors, and other end devices. Also, wireless communications WLAN (wireless Ethernet) are used to connect programmable logic controllers with programmable process automation controllers.

TI's Sitara™ family of ARM microcontrollers feature on-chip Ethernet MAC, CAN, and SDIO modules for WLANs and the performance levels required to support network protocols.

Rice. 2. Microcontrollers of the Sitara AM35x family based on the Cortex-A8 core

The ZigBee protocol has become widespread for the implementation of sensor networks. Based on the IEEE802.15.4 radio specification, the ZigBee interface enables mesh networks to create robust, self-programming networks ideal for industrial applications.

Microcontrollers with the Cortex-M3 core have the required performance to implement the ZigBee protocol and solve related problems, with the exception of organizing a radio channel. Also, the performance of the Cortex-M3 core is sufficient to provide communications in the 10/100 Base T Ethernet standard in half- or full-duplex modes with support for auto-MDIX mode.

A significant advantage of TI's Stellaris® family of ARM Cortex-M3 microcontrollers is their on-chip Ethernet PHY and MAC modules, which can reduce product cost and footprint compared to a traditional dual-chip solution. For projects that require higher performance than 10/100 Ethernet, designers should look to a family of Cortex-A8 microcontrollers such as TI's Sitara family.

The Cortex-M3 core is optimized for single-cycle access to on-chip FLASH and SRAM memory, and provides the designer with performance unattainable in previously marketed microcontrollers. With the ability to access FLASH and SRAM in a single cycle, developers using the Stellaris family of microcontrollers at 50 MHz receive performance comparable to the performance of other controllers at 100 MHz.

3. Man- machine interface

From the point of view of organizing the operation of the system, the human-machine interface (HMI, Human-Machine Interface), which is at the top level of the hierarchy, is the most demanding.

The main user interfaces, which are touch control buttons on the screen, slide bars and basic 2D graphics elements, can be implemented on the basis of a microcontroller, for example, with an ARM Cortex-M3 core. In addition, a high-level operating system is required, so the implementation of the user interface is shifting from microcontrollers towards microprocessor systems.

In automated systems, operators operating from remote workstations must have maximum ability to monitor production and cover as wide a range of production equipment as possible. To achieve meaningful surveillance, higher-level graphics capabilities such as 3D video and graphics are required. For example, one method of providing an operator with the ability to control a distributed control system is to provide access to each part of it by selecting a tab on the graphical display screen corresponding to the mechanism or segment.

Developed implementation options for the human-machine interface have the ability to display data in the form of an algorithmic representation, 2D and 3D graphics, as well as video information from control video surveillance cameras installed in production. It also provides the possibility of window display of parameters of particularly critical processes and properties of manufactured products. Scaling, rendering, and windowing are common properties to all mature HMI implementations. Touch screens and keyboards and voice control are additional input methods, and all require interface or peripheral support from the microprocessor system.

A high degree of interactivity with production processes is required, which includes switching surveillance cameras, receiving current reports on request and the ability to issue control commands production process or technological line. The management console easily provides for receiving and processing information from hundreds of devices of the management network located in its nodes at the lower levels of the hierarchy.

In terms of microprocessor selection, achieving the highest levels of interactivity requires a device with built-in graphics and video processing capabilities, rich I/O functionality, and significant processing power. Also, when choosing a microprocessor, there are many important role The presence of the required peripherals and necessary software libraries plays a role.

Among several families that meet the above-mentioned requirements, processors based on the ARM Cortex-A8 architecture deserve attention. The peripheral, interface, and performance features of these products will be discussed in more detail later in this article.

Design Issues

A key point in making the final decision in choosing a processor is the availability of software, which significantly reduces the time to market for the final product. Software typically includes operating systems, libraries, and communication stacks.

Graphics requirements are often the determining factor when choosing an operating system. Control applications running 2D or 3D graphics, streaming video and high screen resolutions typically also require the use of full real-time operating systems, such as Embedded Linux or Windows™ Embedded CE, installed on processors with ARM9™ or Cortex™-A8 cores, such as ARM microcontrollers of the Sitara™ family, which include a fully functional memory management unit (MMU, Memory Management Unit).

An intelligent display module capable of processing text, 2D graphics primitives and QVGA JPEG images is usually the limit of application for Cortex-M3 based microcontrollers. The Cortex-M3 core includes a Memory Protection Unit (MPU) that facilitates efficient use of compact real-time operating systems and lightweight Linux kernels, such as the Unisom kernel from RoweBots.

One of the benefits of the ARM architecture mentioned earlier is that it is a powerful ecosystem in itself. As a result, there are a large number of certified third-party communications stacks available on the market, including specialized communications protocol stacks required for networking industrial automation equipment. To reduce the time to market for end devices based on TI's Stellaris family of microcontrollers, the StellarisWare® software package is provided, consisting of peripheral driver libraries, a graphics library, and a USB library for organizing both the host and slave ( Device) devices, with support for On-the-Go modes, and a bootloader, in conjunction with an IEC 60730 self-test library, which can be used to diagnose devices as part of industrial applications.

This time-to-market approach extends to the Sitara™ family of microcontrollers, for which hardware development tools, drivers and system support packages (BSPs) are available for open Linux, Windows Embedded CE6 systems, along with third-party support for operating systems such as Neutrino , Integrity and VxWorks.

Energy consumption

Device power consumption has become an important characteristic for all applications, including powered devices. However, while portable device designers are most interested in processor consumption, industrial system designers are focused on maintaining minimal consumption throughout the entire operating time of the equipment to reduce utility and energy costs. Reduced energy consumption also has positive environmental effects.

Almost all enterprises and industries use electric motors, the consumption of which, as a rule, accounts for a large percentage of the total power enterprise consumption. Surprisingly, the ability to operate deterministically plays a significant role in energy efficiency. In the Cortex-M3 family of microcontrollers, the performance of the interrupt processing system has been increased by 60 percent, which significantly reduces the power consumed by the system. A 60 percent faster interrupt system means the microcontroller can stop and start the engine 60 times faster, saving significant energy savings over the course of a year. In addition, the performance of the Cortex-M3 core is suitable for the implementation of intelligent digital switching, which provides the ability to select a less powerful motor for an application, select a more efficient motor, or improve the performance of an existing motor (for example, using space vector modulation in controlling an AC induction motor instead of a simple sine wave algorithm) - all this reduces the overall power consumption of the system. The Stellaris family of microcontrollers have dedicated PWM channels for controlling electric motors with switching pause timers and a quadrature encoder interface (QEI, Quadrature Encoder Interface) for organizing closed control loops, allowing the developer to effectively use the computing capabilities of the Cortex-M3 core to increase performance while reducing power consumption.

Another energy consumption issue in the growing trend of developing fully closed industrial automation systems is protection from dust and other contaminants commonly found in manufacturing environments. If more than just a radiator is used to cool the processor and associated electronics, the designer is forced to provide either air cooling holes and fans, which altogether contradicts the concept of a closed system, or install expensive systems for forced cleaning of incoming air. The advanced Sitara™ family of microcontrollers are designed to solve energy consumption problems by using adaptive software and hardware methods with dynamic control of voltage, frequency and power.

Peripherals and I/O

Multiple processor cores based on standard ARM architecture have a number of advantages. While system-level devices are implemented on microprocessors and microcontrollers, the functional modules provided by chip manufacturers to surround the system-on-chip core are also important. The development of memory functions is of decisive importance. Along with this, since the variety of applications is determined by the richness of the peripherals, the number and types of peripheral modules and I/O interfaces are also key.

Two most important communication blocks - the CAN interface controller and the Enternet network MAC controller, as well as a PHY module with support for the IEEE 1588 standard have already been discussed. The various I/O options are discussed below, many of which are widely used in a wide variety of information transfer applications:

· I2C interface: multi-master serial computer bus designed for connecting low-speed peripherals

· UART/USART: advanced high-speed general purpose peripherals

SPI Interface: A widely used communication method for transmitting data in full duplex mode

I2S audio interface: noise-free signal transmission to external circuits in audio applications

· External peripheral interface (EPI, External Peripheral Interface): configurable memory interface with support modes for SDRAM, SRAM/Flash, 8- and 16-bit Host-Bus peripherals, as well as support for high-speed parallel machine-to-machine data transfer interface (M2M, Machine- to-Machine) with a speed of 150 MB/sec

· USB interface: a communication interface between two or more devices, often combining the ability to work in USB host mode and work in USB On-The-Go mode.

For industrial applications controlling electric motors, mechanization devices and other production equipment, functionality such as high-speed general purpose input/output lines (GPIO, General Purpose Input/Output), pulse width modulation modules (PWM, Pulse Width Modulation) are of greatest importance. , quadrature encoded inputs and channels with analog-to-digital conversion (ADC, Analog-Digital Conversion).

The variety of such functions that can be implemented on a chip is well illustrated in Figure 3, a block diagram of a modern, highly integrated microcontroller.

Rice. 3. Extensive set of Stellaris® 9000 series microcontroller peripherals based on Cortex-M3 core

All the on-chip functionality described earlier is offered by most microcontroller manufacturers. In some cases, a distinctive feature is a design with higher operational reliability characteristics. The integrated IEEE 1588 compliant Ethernet MAC and PHY modules in the Stellaris family of products are a prime example of this distinctive feature of these microcontrollers.

Another example is the programmable real-time unit (PRU) featured in TI's ARM9-based Sitara family of microcontrollers. This module is a small processor with a limited instruction set, and can be configured to perform any special real-time functions not implemented on the main chip.

In industrial control applications, a PRU module is typically configured to provide data I/O functions. This may be a separate interface or I/O block that is not provided in the microcontrollers of any product line. When performing monotonous functions, using a PRU module is more preferable than adding an additional chip in terms of product cost. For example, with the help of PRU, the developer can implement additional standard interfaces, such as UART or industrial Fieldbus and Profibus. The PRU's full programmability even allows developers to profit by adding custom custom interfaces.

Because the PRU is programmable, it can be used as a variety of I/O modules in a variety of environments, thereby increasing system performance while reducing power consumption. For example, a PRU can perform specialized data processing while eliminating the operation of an ARM9 processor for the time being by stopping its clocking.

Conclusion

Microcontrollers are developing at an incredible pace and can be found in a huge number of modern industrial and household appliances: machines, cars, telephones, TVs, refrigerators, washing machines... and even coffee makers. Microcontroller manufacturers include Intel, Motorola, Hitachi, Microchip, Atmel, Philips, Texas Instruments, Infineon Technologies (formerly Siemens Semiconductor Group) and many others.

As more semiconductor companies join the ranks of manufacturers of microprocessors and microcontrollers based on the ARM architecture, industrial control equipment designers will have a wider selection of chips available to implement their projects. The final product choice will be determined by the intelligence of the semiconductor (balanced memory functions, high-speed I/O modules and peripherals, integrated communications that reduce time to market), as well as the availability of quality software development tools, software libraries and industrial protocol stacks. In fact, it will not be enough for a manufacturer to simply have the best microprocessors and microcontrollers in its product range. His highest priority will be to create all the necessary conditions for the developer to quickly start a project - providing ready-made tools and open source software.

Bibliography

1. Frunze A.V. Microcontrollers from Philips family x 51 Volume 1. - Dodeka-XXI, 2005.

2. Belov A.V. A tutorial for device developers using AVR microcontrollers. - Science and technology, 2008

3. Frunze A.V. Microcontrollers? It's that simple. - Dodeka-XXI, 2007

5. Tanenbaum E. Computer architecture. - St. Petersburg: Peter, 2007.

6. "Mathematical foundations of systems theory automatic control", A.R. Gaiduk, Moscow, 2002.

7. Educational and methodological manual for completing a course project in the disciplines “Automated control in technical systems” and “Design of microprocessor systems for industrial electronics”, T.A. Pyavchenko, Taganrog, 1999.

8. “Management of technological processes in the production of microelectronic devices”, V.A. Puzyrev, Moscow, 1984.

9. P.I. Chernysh "Local control systems", Taganrog, 1993.

10. “Digital control systems”, P. Iserman, Moscow, 1984.

11. Guidelines for the development of functional diagrams for the automation of technological processes and production in course and diploma projects, A.S. Klyuev, Ivanovo, 1993.

12. Tavernier K. PIC microcontrollers. Application practice: Transl. from fr. -M: DMKPress, 2008. - 272 pp.: ill. (Handbook Series).

13. Borzenko A.E. IBM PC: device, repair, modernization. - 2nd ed. reworked and additional - M.: Computer Press LLP, 2006. - 344 p.: ill.

14. Digital integrated circuits: Reference/M.I. Bogdanovich, I.N. Grel, V.A. Prokhorenko, V.V. Shalimo.-Mn.: Belarus, 2001. - 493 p.: ill.

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Modes of application of “TKM - 52” in automated process control systems

The “TKM - 52” controller is designed to collect, process information and generate impacts on the control object as part of distributed hierarchical or local autonomous automated process control systems based on an Ethernet or RS-485 (MODBUS) network. The controller can be used:

a) as an autonomous device for controlling small objects;

b) as a remote communication terminal with an object as part of distributed control systems;

c) simultaneously as a local control device and as a remote communication terminal with an object as part of complex distributed control systems.

The controller in redundant mode is designed for use in highly reliable control systems. Depending on the design options, one of the operating systems can be installed in the controller: DOS or System Software (SPO) based on OS LINUX. In the first case, MFK can be carried out using universal programming tools using the TRA - CE MODE program.

In stand-alone applications, the controller solves problems of medium information capacity (50 - 200 channels). You can connect various peripheral devices to it via serial (RS - 232, HRS - 485) and parallel interfaces, as well as via Ethernet. The built-in keyboard and indicator unit V03 can be used as an operator-technologist console.

In the mode of using a remote terminal for communication with an object, the control program is executed on a computing device of the top level of the hierarchy (for example, on an IBM PC) connected to the controller via a serial channel (RS - 232 or RS - 485. Modbus protocol), or via an Ethernet network , and the controller ensures the collection of information and the issuance of control actions on the object.

Application in mixed mode (as an intelligent node of a distributed automated process control system), the object is controlled by an application program,

stored in the controller's non-volatile memory. In this case, the controller is connected to the Ethernet network, which allows the computing device at the top level of the hierarchy to have access to the values ​​of the controller’s input and output signals and the values ​​of the operating variables of the application program, as well as to influence these values. The controller can use all available interfaces, as well as its keyboard and indicator. Simultaneous execution of the application program and operation over the Ethernet network is supported by the controller's operating system and I/O system.

This option uses the resources of the TKM 52 controller to the greatest extent, and allows you to create flexible and reliable distributed automated process control systems of any information capacity (up to tens of thousands of channels). This ensures the survivability of individual subsystems.

Composition and characteristics of the controller

The TKM - 52 controller is a design-assembled product, the composition of which is determined when ordering. The controller consists of a base part, a keyboard-display unit and input/output modules (from 1 to 4). The basic part of the controller consists of a housing, a power supply, a PCM423L processor module with a TCbus52 module and a V03 keyboard and display unit.

The controller body is made of metal and consists of sections connected to each other using special screws. The rear section houses the power supply and processor module. The remaining sections house I/O modules. The front section always houses the keyboard and display unit V3. Depending on the number of sections for I/O modules, the following configurations of the base part of the controller differ:

The “TKM - 52” controller operates from an alternating current network with a frequency of 50 Hz and a voltage of 220 V, power consumption is 130 W.

The TKM - 52 controller is designed for continuous round-the-clock operation.

The range of operating temperatures of the environment surrounding the controller is from plus 5 to plus 50 C. The controller has a dust-splash-proof design IP42.

Main characteristics of the processor module:

a) processor: FAMD DX-133(5x86-133);

b) system RAM - 8 MB, depending on the installation of the memory module, can be expanded up to 32 MB;

c) FLASH - memory of system and application programs - 4 MB (can be expanded up to 144 MB;

d) serial ports: COM1 RS232, COM2 RS232/RS485 compatible UART 16550, parallel port LPT1: supports SPP/EPP/ECP modes;

e) Ethernet interface: Realtek RTL8019AS controller, NE2000 software compatible;

e) WatchDog hardware reset timer, astronomical calendar-timer powered by a built-in battery, power supply - 5 V ± 5%, 2 A.

The industrial applications of microcontrollers are very wide. These include decision automation, motor control, human-machine interfaces (HMI), sensors and programmable logic control. Increasingly, designers are introducing microcontrollers into previously “mindless” systems, and the rapid spread of industrial IoT (Internet of Things) is significantly accelerating the implementation of microcontrollers. However, industrial applications require lower consumption electrical energy and its more rational use.

Therefore, microcontroller manufacturers are introducing their products into industrial and related markets, while offering high performance and flexibility, but with minimal power consumption.
Content:

Requirements for industrial microcontrollers

Typically, industrial environments place greater demands on electrical equipment due to harsher operating conditions, such as possible electrical noise and large current and voltage surges caused by the operation of powerful electric motors, compressors, welding equipment and other machines. Electrostatic and electromagnetic interference (EMI) and many others may also occur.

Low supply voltage and geometric processes of 130 nm (feature density. Achieved in 2000-2001 by leading chip companies) or less do not handle the hazards listed above. To eliminate possible emergency situations, special external protection circuits are used, special boards that are located between the power part and the ground. If microcontroller manufacturers want to conquer the modern global market, they need to adhere to several requirements, which we will discuss below.

Low power consumption

Modern control and monitoring systems are becoming increasingly complex, increasing the requirements for processing in individual remote sensor units. Does this data need to be processed locally or use an ever-increasing number of digital communication protocols? Most modern developers include a microcontroller in the measurement sensor to add additional functions to it. Modern systems include motor condition monitors, functions for remote measurement of liquids and gases, control of control valves, and so on.

Many industrial sensor assemblies are located significantly away from power sources, where the big disadvantage is the voltage drop on the line from the source to the sensor. Some sensors use a current loop where losses are lower. But regardless of the power supply, low power consumption of the microcontroller is a must.

There are also battery-powered systems - building automation systems, fire alarms, motion detectors, electronic locks and thermostats. There are also many medical devices, such as blood glucose meters, heart rate monitors and other equipment.

Technology has not kept pace with the ever-increasing capabilities of smart systems, which increases the need to minimize the energy consumption of system elements. The microcontroller must consume a minimum of electricity in operating mode and be able to switch to the “sleep” mode with minimal energy consumption, as well as “wake up” when given condition(internal timer or external interrupt).

Ability to save data

An important note about battery performance: Every battery will eventually discharge and may not be able to maintain the required power output. Yes, if your mobile phone turns off in the middle of a conversation, it will cause irritation, but if a medical device turns off during an operation or a complex production cycle system, this can lead to very tragic consequences. When powered from the mains, the voltage may disappear due to a large overload or an accident on the line.

In such situations, it is very important that the microcontroller is able to calculate the shutdown situation and save all important operating data. It would be very nice if the device could save the states of the CPU, program counter, clock, registers, I/O states, etc., so that after re-operation the device can resume its operation without a cold start.

Multiple communication options

When it comes to communications, in industrial applications gamma is controlled. At the same time, in wired communications there are almost all types, ranging from the classic current loop 4 - 20 mA and RC-232 to Ethernet, USB, LVDS, CAN and many other types of exchange protocols. As IoT gained popularity, wireless communication protocols and mixed protocols began to appear, for example, Bluetooth, Wi-Fi, ZigBee. In simple terms, the likelihood that this industry will settle on any one data exchange protocol is zero, therefore modern microcontrollers should accommodate a range of communication options.

Safety

The latest version of the Internet protocol IPv6 has a 128-bit address field, which gives it a theoretical maximum of 3.4 x 10 38 addresses. That's more than grains of sand in the world! With such a huge number of devices potentially open to the outside world, it becomes topical issue security. Many existing solutions are based on the use of open source software such as OpenSSL, but the results of this use are far from the best.

A few horror stories did occur. In 2015, researchers armed with a laptop and mobile phone hacked Jeep Cherokee using a wireless Internet connection. They even managed to disable the brakes! Naturally, this drawback was eliminated by the developers, but the danger remains. The possibility of hacking modern systems connected to the Internet keeps IoT experts in suspense, because if they were able to hack a car, they could hack the system of an entire plant or factory, and this is much more dangerous. Remember Stuxnet?

A key requirement for modern industrial microcontrollers is robust software and hardware security features such as AES encryption.

Scalable set of core options

A product that tries to satisfy all users will ultimately satisfy no one.

Some industrial applications prioritize low power consumption. For example, a wireless monitoring system for recording temperature in a food freezing system, or a patch-on sensor system for collecting physiological data. This system spends most of its working time in sleep mode and periodically wakes up to perform a few simple tasks.

A large-scale industrial project will combine microcontrollers with different performance and power combinations. To speed up processing and speed up time to market, it must easily port application code between cores, depending on functional tasks.

Flexible set of peripherals

Given the enormous volumes of industrial control, processing and measurement, any industrial family of microcontrollers must have a minimum set of peripheral devices. Some of the “minimum set”:

• Medium resolution (10-, 12-, 14-bit) analog-to-digital ADC converters operating at speeds up to 1MSamples/s;
• (24-bit) high resolution for lower speeds of high-precision applications;
• Several serial communication options, especially I2C, SPI and UART, but preferably USB;
• Security features: IP protection, Advanced Encryption Standard (AES) hardware accelerator;
• Built-in LDO and DC-DC converters;
• Specialized peripherals to perform common tasks, such as capacitive touch switch module, LCD panel driver, transimpedance amplifier and so on.

Powerful development tools

New projects are becoming more complex and require improved and faster development processes. In order to keep up with current trends, any family of industrial microcontrollers must have full support at all stages of development and operation, which includes software, development tools and tools.

The software ecosystem should include a GUI IDE, an RTOS, a debugger, coding examples, code generation tools, peripheral settings, diver libraries, and APIs. There should also be support for the design process, preferably with online access to factory experts, as well as online user chat where tips and recommendations can be exchanged.

MSP43x Family of Low Power Industrial Microcontrollers

Several manufacturers have developed solutions to meet the demand of the growing market. One of bright examples Such manufacturers include Texas Instruments with its MSP43x family, which offers an excellent combination of high performance and low power consumption.

More than 500 devices are included in the MSP43x line, including even the ultra-low power MSP430, based on a 16-bit RISC core, and the MSP432, which can combine high level performance with ultra-low power consumption. These devices have a 32-bit ARM Cortex-M4F floating point core with up to 256 KB of flash memory.

The MSP430FRxx is a family of 100 devices that utilize ferroelectric random access memory (FRAM) for unique performance capabilities. FRAM, also known as FeRAM or F-RAM, combines the features of flash and SRAM technologies. It is non-volatile with fast write and low power consumption, 10-15 cycle write endurance, improved code and data security compared to flash or EEPROM, and increased resistance to radiation and electromagnetic emissions.

The MSP43x family supports a variety of industrial and other low-power applications, including network infrastructure, process control, test and measurement, home automation, medical and fitness equipment, personal electronic devices, and more.

Ultra-low power example: nine-axis sensors combined with MSP430F5528

In research and measurement applications, an increasing number of sensors are being “fused” into a single system and use common software and hardware to combine data from multiple devices. Data fusion corrects individual sensor deficiencies and improves performance when determining position or orientation in space.

The diagram above shows a block diagram of an AHRS that uses a low-power MSP430F5528, along with a magnetometer, gyroscope, and accelerometer on all three axes. MSP430F5528 optimizes and expands life cycle batteries of a portable measuring device containing a 16-bit RISC core, a hardware multiplier, a 12-bit ADC and several serial modules including USB.

The software uses a direction-cosine-matrix (DCM) algorithm that takes calibrated sensor readings, calculates their orientation in space and outputs values ​​in the form of height, roll, and yaw, called Euler angles.

If necessary, the MSP430F5xx can interact with motion sensors via a serial I 2 C protocol. This can benefit the entire system as the main microcontroller is freed from processing sensor information. It can remain in standby mode, thereby reducing power consumption, or use freed resources for other tasks, thus increasing system performance.

Example of a high performance application: BPSK modem using MSP432P401R

Binary phase shift keying (BPSK) is a digital modulation scheme that conveys information by changing the phase of a reference signal. A typical application would be an optical communication system that uses a BPSK modem to provide an additional communication channel for low data rate signals.

BPSK uses two different signals to represent binary digital data in two different modulation phases. The carrier of one phase will be bit 0, while the phase shifted by 180 0 will be bit 1. This data transfer is shown below:

The MSP432P401R forms the core of the design. In addition to the 32-bit ARM Cortex-M4 core, this device has a 14-bit, 1-MSa/s ADC and CMSIS digital signal processing (DSP) library, allowing it to efficiently handle complex DSP functions.

The transmitter (modulator) and receiver (demodulator) are shown below:

The implementation includes BPSK modulation and demodulation, forward error correction, error correction to improve BER, and digital signal conditioning. BPSK includes an optional finite impulse response (FIR) low-pass filter to improve the signal-to-noise ratio (SNR) prior to demodulation.

BPSK modulator characteristics:

• carrier frequency 125 kHz;
• bit rate up to 125 kbit/s;
• Full packet or frame up to 600 bytes;
• x4 media oversampling at 125 kHz (i.e. 500 kSamples/s sampling rate)

conclusions

Microcontrollers for industrial use must have a combination of high performance, low power consumption, flexible feature set, and a strong software development ecosystem.

The article discusses the role of microcontrollers (MC) in industrial automation systems, in particular, we will talk about how a real-world interface for various types of sensors and actuators is implemented on the basis of microcontrollers. We will also discuss the need to integrate high-performance cores, such as the ARM Cortex-M3, into microcontrollers with the precision and specialized peripherals found in the company's ADuCM360 series and Energy Micro's EFM32 family of microcontrollers. Also not to be ignored is the relatively new communication protocol that is focused on this application area, with specific reference to the budget microcontrollers of the XC800 / XC16x family () and (), and to specialized transceivers, including ().

Microcontrollers integrate technical capabilities for mixed signal processing and computing power, while the level of performance of MCUs and their functionality is constantly growing. However, there are other developments that can extend the life cycle of low-cost and low-performance microcontrollers.

By definition, microcontrollers are useless without communication with " real world" They were designed to act as hubs for inputs and outputs, performing conditional branch tasks and controlling serial and parallel processes. Their role is determined by the control, while the ability to program means that the nature of the control is determined by logic. However, they were originally designed to provide an interface to the analog world, and therefore microcontrollers rely heavily on the analog-to-digital conversion process to operate. Often this is a digital representation of an analog parameter, usually obtained from some kind of sensor, on the basis of which the control process is based, and the main application of the microcontroller in this case is seen in automation systems. Ability to manage large and complex mechanical systems, using a miniature and relatively cheap "piece" of silicon, contributed to the fact that microcontrollers have become the most important element industrial automation systems, and it is not surprising that many manufacturers began to produce specialized families of microcontrollers.

Precision work

For commercial reasons, it is expected that data conversion, a key function of microcontrollers, should be cost-effectively implemented into the microcontroller, resulting in an increased level of integration of mixed-signal processing functionality. In addition, an increase in the level of integration increases the load on the core.

The low cost and flexible functionality of microcontrollers means microcontrollers are widely used in a variety of applications, but manufacturers are now looking to integrate multiple functions into a single microcontroller for reasons of cost-effectiveness, complexity, or security. Where once dozens of microcontrollers may have been used, now only one is needed.

It is therefore not surprising that what started out as 4-bit devices has now evolved into very complex and powerful 32-bit processor cores, with the ARM Cortex-M core becoming the choice of many manufacturers.

Combining a high-performance processor core with precise and stable analog functionality is not an easy task. CMOS technology is ideal for high speed digital circuits, but there may be problems with the implementation of sensitive analog peripherals. One of the companies with extensive experience in this area is Analog Devices. The company's family of fully integrated ADuCM data acquisition systems are designed to interface directly with precision analog sensors. This approach not only reduces the number of external components, but also ensures the accuracy of the conversion and measurements.

The converter, integrated into an ARM Cortex-M3 ADuCM360 system for example, is a 24-bit sigma-delta ADC that is part of the analog subsystem. This data acquisition system integrates programmable drive current sources and a bias voltage generator, but the more important part is the built-in filters (one used for precision measurements, the other for fast measurements) that are used to detect large changes in the original signal.

Working with sensors in “deep sleep” mode

Microcontroller manufacturers are recognizing the important role of sensors in automation systems and are beginning to develop optimized analog input circuits that provide a specialized interface for inductive, capacitive and resistive sensors.

Even analog input circuits have been developed that can operate autonomously, such as the LESENSE (Low Energy Sensor) interface in Energy Micro's ultra-low power microcontrollers (Figure 1). The interface consists of analog comparators, a DAC and a low-power controller (sequencer), which is programmed by the microcontroller core, but then operates autonomously while the main part of the device is in “deep sleep” mode.

The LESENSE interface controller operates from a 32 kHz clock source and controls its activity, while the comparator outputs can be configured as interrupt sources to “wake up” the processor, and the DAC can be selected as the comparator reference source. LESENSE technology also includes a programmable decoder that can be configured to generate an interrupt signal only when multiple sensor conditions are met at the same time. Digi-Key offers the EFM32 Tiny Gecko Starter Kit, which includes the LESENSE demo project. Microcontrollers of the Tiny Gecko family are based on the ARM Cortex-M3 core with an operating frequency of up to 32 MHz and are aimed at use in industrial automation systems that require measuring temperature, vibration, pressure and recording movements.

IO-Link protocol

The introduction of a new powerful sensor-actuator interface is helping many manufacturers extend the lifecycle of their 8- and 16-bit microcontrollers in the industrial automation arena. This data interface protocol is called IO-Link and is already supported by leaders in the industrial automation sector and, in particular, by microcontroller manufacturers.

Data transmission using the IO-Link protocol is carried out over a 3-wire unshielded cable over distances of up to 20 meters, which makes it possible to integrate intelligent sensors and actuators into existing systems. The protocol implies that each sensor or actuator is "intelligent", in other words, each point is implemented on a microcontroller, but the protocol itself is very simple, so an 8-bit microcontroller will be sufficient for these purposes, and this is exactly what is currently used by many manufacturers.

The protocol (also known as SDCI - Single-drop Digital Communication Interface, regulated by the IEC 61131-9 specification) is a point-to-point network communication protocol that communicates sensors and actuators with controllers. IO-Link makes it possible for smart sensors to transmit their status, parameters of all settings and internal events to controllers. As such, it is not intended to replace existing communication layers such as FieldBus, Profinet or HART, but can work alongside them to simplify the communication of low-cost microcontrollers with precision sensors and actuators.

A consortium of manufacturers using IO-Link believes that system complexity can be significantly reduced, as well as introducing additional useful features, for example, real-time diagnostics through parametric monitoring (Figure 3). When integrated into a FieldBus topology via a gateway (again, implemented on a microcontroller or programmable logic controller), complex systems can be monitored and controlled centrally from the control room. Sensors and actuators can be configured remotely, in part because IO-Link specification sensors know much more about themselves than “regular” sensors.

First of all, we note that the proprietary (and manufacturer) identifier and various settings are built into the sensor in XML format and are available upon request. This allows the system to instantly classify the sensor and understand its purpose. But more importantly, IO-Link allows sensors (and actuators) to provide data to the controller continuously in real time. In fact, the protocol involves the exchange of three types of data: process data, service data and event data. Process data is transmitted cyclically, and service data is transmitted acyclically and at the request of the master controller. Service data can be used when writing/reading device parameters.

Several microcontroller manufacturers have joined the IO-Link consortium, which recently became a Technical Committee (TC6) within the international PI community (PROFIBUS & PROFINET International). Essentially, IO-Link establishes a standardized method for controllers (including microcontrollers and programmable logic controllers) to identify, control, and communicate with sensors and actuators that use the protocol. The list of manufacturers of IO-Link-compatible devices is constantly growing, as is comprehensive hardware and software support for microcontroller manufacturers.

Some of this support comes from companies specializing in this field, for example Mesco Engineering - German company, which partners with a number of semiconductor manufacturers to develop IO-Link solutions. The list of its partners includes quite large and well-known companies: Infineon, Atmel and Texas Instruments. Infineon, for example, has ported Mesco's software stack to its 8-bit XC800 series microcontrollers, and is also supporting IO-Link master development on its 16-bit microcontrollers.

The stack developed by Mesco has also been ported to the Texas Instruments MSP430 series 16-bit microcontrollers, specifically the MSP430F2274.

Manufacturers are also focusing on developing discrete IO-Link transceivers. For example, Maxim produces the MAX14821 chip, which implements a physical layer interface to a microcontroller that supports the data link layer protocol (Figure 4). Two internal linear regulators produce a common supply voltage of 3.3 V and 5 V for the sensor and actuator; connection to the microcontroller for configuration and monitoring is carried out via the SPI serial interface.

It is likely that due to the ease of implementation and adoption of the IO-Link interface, more manufacturers will integrate this physical layer with other specialized peripherals found in microcontrollers for use in industrial automation systems. Renesas has already introduced a range of specialized IO-Link Master/Slave controllers based on its 16-bit 78K family of microcontrollers.

Industrial automation systems have always depended on a combination of measurement and control. Over the past few years, there has been a significant increase in the level of industrial network communications and protocols, however, the interface between the digital and analog parts of the system has remained relatively unchanged. With the introduction of the IO-Link interface, sensors and actuators currently being developed are still able to interface with the microcontroller in a more sophisticated manner. The point-to-point communication protocol not only provides an easier way to exchange data to control system elements, but also expands the capabilities of low-cost microcontrollers.