Interface 1-wire

Single-wire the interface 1-Wire developed in the late nineties by Dallas Semiconductor Corp firm., p>>>

• devices in special MicroCAN cases for the solution of problems of identification, transfer or transformation information (iButton technology),
• programming of the built-in memory of integrated components,
• automation systems (technology of networks of 1-Wire-networks). to

  If the first application is widely known to div in the world market, and for a long time enjoys deserved popularity, and the second with success provides possibility of easy reorganization of functions of semi-conductor components with small quantity of the external conclusions made by Dallas Semiconductor Corp firm., that automation systems on the basis of the 1-Wire-tire yet did not receive due recognition. Earlier such situation was defined, the extremely limited set of components for the organization of applications in the field of automation. However, recently appears more and more messages and concrete examples of use of the 1-Wire-interface in the most various areas, more and more developers show interest to this technology that is connected, first of all, with considerable extension of the nomenclature of single-wire components.

  So in what feature of this network standard? After all as Wednesday for information transfer on the single-wire line use of a usual telephone cable and, therefore, speed of an exchange in this case more often is possible is not great. However, if attentively to analyse the majority of objects demanding automation, more than for 60 % from them speed limit of service in 15,4kbit/second will be more than satisfactory. And other advantages 1-Wire, such as:

  • the simple and original solution of an adresuyemost of subscribers,
  • the simple protocol,
  • simple structure of the communication line,
  • small consumption of components,
  • easy change of a configuration of a network,
  • considerable extent of communication lines,
  • exclusive low cost of all technology as a whole, tells li to ul about need to pay the closest attention to this effective tool for the solution of problems of complex automation in the most various spheres of activity.

  the Basic principles

  1-Wire-net represents the information network using for implementation of digital communication one line of data and one returnable (or earth ) a wire. Thus, the available cables containing neekranirovanny twisted pair of this or that category can be applied to realization of the environment of an exchange of this network, and even a usual telephone wire. Such cables at their laying do not demand existence of any special equipment, and restriction of the maximum length of the single-wire line is regulated by developers at level 300м.

  the Basis of architecture of 1-Wire-networks, is topology of the general tire when each of devices is connected directly to the uniform highway, without any cascade connections or branchings. Thus as the base the network structure with one leading or the master and numerous conducted is used. Though there is a number of specific receptions of the organization of work of single-wire systems in a mode of the multimaster.

  the Configuration of any 1-Wire-network can change any way in the course of its work, without creating hindrances of further operation and operability of all system as a whole if at these changes the basic principles of the organization of the single-wire tire are observed. This possibility is reached thanks to presence at the protocol of the 1-Wire-interface of special team of search of conducted devices ( ROM Search ) which allows to define new participants of information exchange quickly. Standard speed of working off of such team makes ~75 knots of a network a second.

  Thanks to existence as a part of any device supplied with the network version of the 1-Wire-interface, the unique individual address (absence of coincidence of addresses for the devices which ever are let out by Dallas Semiconductor Corp., it is guaranteed by the manufacturing firm), such network has almost unlimited address space. Thus, each of single-wire devices is ready at once to use as a part of a 1-Wire-network, without any additional hardware-software updatings. Single-wire components are samotaktiruyemy semi-conductor devices, at the heart of exchange of information between which, management of change of duration of time intervals of pulse signals in the single-wire environment and their measurement lies. Signaling, for the 1-Wire-interface, asynchronous and half-duplex, and all information circulating in a network, is perceived by subscribers either as teams, or as data. Teams of a network are generated by the master and provide various options of search and addressing of conducted devices, define activity on lines even without direct addressing of separate components, br/>
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  Standard speed of work of a 1-Wire-network which makes 15,4kbit/second, was chosen, first, taking into account ensuring the maximum reliability of data transmission on big distances, and, secondly, taking into account speed of the most widespread types of microcontrollers which generally should be used at realization of leading devices of the single-wire tire. This value of speed of an exchange can be reduced to any possible value thanks to introduction of a compulsory delay between transfer to the line of separate bits of data (extension of temporary slots of the protocol). Or it is increased at the expense of transition to the special accelerated mode of an exchange (speed of Overdrive - to 125kbit/second) which is allowed for separate types of single-wire components on small on distance, the high-quality communication line not overloaded with another devices.

  At realization of the single-wire interface are used by p standard KMOP/TTL logic levels of signals, and a food of the majority of single-wire components can be carried out from an external source with working tension in a range from 2,8В to 6,0В. As alternative to application of an external food serves, so-called, the mechanism of "a parasitic food" which action consists in use by each of conducted components of the 1-Wire-line of electric energy of the impulses transferred on the tire of data which accumulates in the special capacity built in the device. Besides, separate components of single-wire networks can use a diet on the tire of data when energy to the receiver arrives directly from the master on the communication line, thus exchange of information in a network compulsorily stops.

  Perhaps, especially attractive quality of technology 1-Wire is exclusive simplicity of control, debugging and network service practically any configuration constructed on this standard. Really, to start work enough any personal computer, the inexpensive adapter of the 1-Wire-line, and also freely extended Dallas Semiconductor Corp firm. iButton Viewer programs. In the presence of this small number of components control and management of a network practically any complexity constructed on the basis of standard single-wire components, will be organized literally within several minutes. The iButton Viewer program, in this case, allows with the maximum comfort for the developer to identify any of conducted single-wire devices on lines and to check in full correctness of its functioning as a part of a configured network.

  the Organization of leaders

  Separate types of adapters which allow to allocate any personal computer with possibility to serve as the master a 1-Wire-network, are issued the firm Dallas Semiconductor Corp. Adapters concern them for parallel port of the DS1410E type, for DS9097E and DS9097U type COM port, for DS9490R type USB port. These devices have various functionality and design features that provides to the developer the maximum freedom of choice when designing. And existence at the user of small skills in creation of electronic equipment, allows to make easily independent assembly of the circuit of the elementary adapter of a 1-Wire-network for the computer from a small number of available electronic components.

  Often as the leader of the single-wire tire the computer, and the elementary universal microcontroller acts not. For the organization of its interface to a 1-Wire-network various hardware-software methods are used. From the elementary when the operating program of the controler completely realizes the 1-Wire-interface protocol on one of the functional two-forked conclusions connected with the single-wire line, to the options, allowing to liberate considerable resources of the controler, thanks to specialized chips of interface to a 1-Wire-network. Such chips are connected to the processor playing a role of the leader of the single-wire tire, through the peripheral knots of input-output which are a part of any universal microcontroller. For example, the DS1481 device is intended for connection directly to functional conclusions of a parallel exchange of the controler. And for the organization of the master of single-wire system on the basis of microcontrollers with 3хвольтовым a food the passive chips of DS1482 which are carrying out coordination with levels of signals of the standard 1-Wire-highway are delivered. If the master of the single-wire line has to be organized on the basis of standard knot of the consecutive UART interface of the microcontroller, DS2480В chip is used, and the chip of DS2490 adapts the single-wire line for work from the built-in knot of the UBS interface. Both chips realize the so-called programmed mechanism of an active tightening of the tire of data of the 1-Wire-highway, providing high-quality signaling in long problem lines and increase in loading ability of the leader by number of conducted devices served by it. By the way the majority is higher than the mentioned adapters for personal computers, are also constructed on the basis of similar chips. Moreover, considering features of work of modern operational environments of Windows, use of these components which in essence are digital machine guns operated on the consecutive interface, provides full-scale service of single-wire lines in real time.

  At creation of the difficult finished microprocessor systems having deficiency of machine time for implementation of the 1-Wire-protocol, the most rational is idea about assignment of a separate task of service of the single-wire line on special knot of custom-made or semicustom SBIS, for the subsequent interface of such digital machine gun, through the system highway, is direct with the main processor knot. Dallas Semiconductor Corp firm. even developed a set of recommendations about the organization of similar knot under the name DS1WM which was realized, including, experts of Xilinx Inc. in the form of the finished practical example for programmed reconstructed matrixes of Virtex and Spartan families. Moreover, and Dallas Semiconductor Corp., which including is known as the supplier of high-speed controlers of a clone of MCS51, lets out specialized coherent the DS80C400 microcontroller which contains the machine gun of support of the 1-Wire-protocol built in a crystal with possibility of realization of the mechanism of an active tightening.

  Rather perspective the direction connected with use of pocket computers (or PDA (Personal Digital Assistant)) the popular PalmOS, Handspring and WinCE/PocketPC platforms for service of single-wire components, including working as a part of 1-Wire-networks is represented also. Thus, to PDA connection to the single-wire tire apply specialized adapters of a serial port which differ small consumption and are constructed on the basis of the circuit decisions using above than listed chips of interface to the 1-Wire-line. Such approach is now the most rational at the organization of independent and mobile 1-Wire-systems.

  the Problem of preparation of the software for management of the master of the line at service of 1-Wire-networks, also is not represented unsoluble. Dallas Semiconductor Corp firm. freely the professional software package of the developer iButton TMEX SDK being a universal remedy for professional programmers which considerably simplifies process of creation of programs for service of the single-wire devices connected through standard types of adapters to personal computers which are equipped with the Windows operating system extends. It contains a set of the debugged drivers and utilities for implementation of the full-scale 1-Wire-protocol. As the interaction environment with the developer the iButton TMEX SDK package uses the special standardized program API interface. Besides, from the fttp-server of campaign of Dallas Semiconductor Corp. a number of examples of implementation of the 1-Wire-protocol is freely available to some, most popular types of microprocessors, and also ready libraries of functional program modules of the single-wire interface for various program platforms.

  Conducted single-wire components

  The conducted single-wire components containing the 1-Wire-interface, are issued in two different types. Or in the MicroCAN cases similar outwardly to the disk metal accumulator, or in ordinary cases for installation on the printed-circuit board. MicroCAN case hollow inside. It carries out function of protection of a semi-conductor crystal of a single-wire chip containing in it which is connected to the outside world only through two, isolated from each other, the halves of the case being in essence contact platforms for connection of the single-wire line. In similar "tabletochny" cases iButton devices are delivered, as a rule. Components which are intended for use as a part of 1-Wire-networks, are packed in the plastic cases used for manufacturing of transistors and integrated circuits. Such approach speaks that unlike iButton devices single-wire devices for 1-Wire-networks often have more than two conclusions. Besides conclusions which are required for data exchange on onethe wire highway, they have additional conclusions necessary, for ensuring their food and the organization of the external chains connecting such devices with objects of automation, for example, by sensors or actuation mechanisms.

  To the simplest conducted single-wire components treat the silicon serial number DS2401 (or the modified option of this device with an external food of DS2411) and the electronic key of DS2405 operated on the 1-Wire-interface. The first of these devices is often used as an electronic label which allows to identify a condition, for example, the mechanical switch switching the line of data of the single-wire interface. By means of DS2405 it is possible to carry out distantly the simplest functions of switching of the external equipment, changing a condition of an operated key of rather returnable conductor of the 1-Wire-highway.

  However, the most popular conducted components on the basis of which the greatest number of applications is realized, perhaps, digital thermometers of the DS18S20 type (better known under designation of the laid-off DS1820 device which is not made any more, but managed to become the international brand), certainly, are. Advantages of these digital thermometers from the point of view of the highway organization, in comparison with any other integrated temperature sensors, and also quite good metrological characteristics and a good noise stability, deduce them on the first place at creation of multipoint systems of temperature control in a range from - 55°С to +125°С. They allow not only to carry out direct monitoring of temperature in real time, but also thanks to existence of the built-in non-volatile memory of temperature ustavka, can provide the priority alarm system to the line about the fact of an exit of controllable parameter out of limits of preset values. Also, more perfect DS18В20 devices, speed of transformation in which is defined by word length of result which is programmed by the master of the line directly during their service are delivered. The digital code which is read out from such thermometer, is direct result of the measured value of temperature and does not need additional transformations. And their not calibrated, but during too time cheaper version under DS1822 designation, is represented the optimum decision for developers of inexpensive multipoint monitoring systems of temperature processes. For the consumers using only parasitic diet of the single-wire line, Dallas Semiconductor Corp campaign. lets out economic dvukhvyvodny devices - DS18S20-PAR, DS18B20-PAR, DS1822-PAR. The Russian firm Rainbow Technologies received the certificate of Gosstandart of Russia on the statement as gages including the single-wire digital thermometers DS1822, DS18B20, DS18S20, DS1920 made by firm Maxim Integrated Products, Inc., which structure includes Dallas Semiconductor Corp. In confirmation of this fact there is a document that these types of devices are registered in the State register of measuring instruments at No. 23169-02 and are allowed to application in the Russian Federation.

  Four-channel single-wire ATsP of the DS2450 type and two-channel single-wire the counter combined with buffer memory, the DS2423 type allow to solve the problems connected with numbering of analog and pulse and time signals. The first of these devices in essence resolves a problem of service of sources of analog information as a part of 1-Wire-networks which the majority of sensors of various physical sizes let out now (pressure, weight, tension, humidity, a current, illumination, acceleration, the same temperature, but in ranges inaccessible to registration by means of use of digital thermometers etc. concerns) . The second device can serve with success many types of pulse sensors applied in equipment (various optical counters, sensors of quantity of turns, a target signal from flowmeters revolving objects, the capacitor sensors of the humidity which have been switched on in setting chains of operated generators of impulses, counters of level radiation integrating converters of tension into frequency etc.).

  But after all the most irreplaceable "bricks" underlying the base of single-wire networks of automation, are universal dual addressed transistor keys of the DS2406P type (the modern version of widely known DS2407P devices). On the basis of these devices the mass of applications, and, first of all, knots of control of logic conditions (levels) and circuits of service of sensors of "dry contact", and also various key circuits can be realized. Thus, thanks to these components collecting discrete information from territorially dispersed sensors (monitors of doors, contactors of provision of fittings, any sensors having an exit YES/NO, somehow sensors of situation, pass, presence, the fire and security alarm system etc.) is carried out. Similar devices provide management of switching of any kinds of the power equipment which have two working conditions: it is included/is switched off (heaters, conditioners, motors, fans, armaturny latches etc.) . Besides, two-forked, individually programmed conclusions of DS2406P can be used for the organization of the slow consecutive interface between the local microcontroller and a 1-Wire-network. Despite low speed at realization of a similar way of exchange of information on a single-wire network when one bit of data is transferred for two standard parcels, such decision is accepted and rather reliable for a large number of concrete applications.

  Nevertheless, firm Dallas Semiconductor Corp. as standard "bridge" of an exchange between any circuits constructed on microcontrollers of various types, and 1-Wire-networks use of specialized two-port static memory of DS2404 is recommended. As to the massif of memory of this device access is possible, both from the single-wire tire, and from the subordinated consecutive interface operated by the microcontroller, exchange of information between the leader of a network and the subordinated intellectual device solving any local task, is made rather easily. Moreover, thanks to existence as a part of a chip of DS2404 of additional knot of a real time clock and a calendar, supply of the data kept by the processor in the general massif of memory, individual temporary labels is possible.

  on the basis of knot of a real time clock of a crystal of DS2404 Dallas Semiconductor Corp campaign. two more components, single-wire systems of automation very useful to creation are issued. It DS2415 and DS2417 devices. Applying any of these devices it is possible to organize cheap hours/calendar with the single-wire network interface. Besides, the second device thanks to existence in its structure of a separate conclusion of interruption, can operate also in addition on time switching of the external equipment or provide synchronization of operation of other devices with the processes occurring on the 1-Wire-line.

  Considerably expands with p possibilities of single-wire networks on analog management dispersed, including power, the equipment a digital potentiometer of DS2890 completed with the network 1-Wire-interface. Using this device it is possible to create the most various systems of remote unaccented management, thanks to possibility of smooth change of an analog regulating signal on 256 gradation.

  At all variety of single-wire components, it is obvious that most universal of them is the unique DS2408 device. It is individually two-forked eight-digit port of input-output freely digit-by-digit programmed on the 1-Wire-tire which allows to realize any interface between the external device of any updating and the single-wire line. This device has the two-forked conclusion of external synchronization providing hardware clocking of transferred or accepted data. Use of a chip of DS2408 allows to provide management of 1-Wire-tire means: the concentrated two-forked input-output on 8 independent channels, a drive of svetodinamichesky, liquid crystal indicators and displays of different types, scanning of matrix keyboards and discrete sensors of the most various types and as allows to realize really full-scale interface with various types of microcontrollers, both in consecutive, and in a parallel fashion.

  Some components of 1-Wire-networks contain in the structure the constant massif (once filled by the user) or non-volatile memory of this or that volume. It allows to store the special office information connected with application of a concrete component and features of its use (the identifier, territorial situation, calibration factors, dimension, value of ustavka by default etc.) directly as a part of the single-wire device. Thanks to it for the organization of work of each new single-wire network it is not necessary to prepare the separate special software, it is enough to have one standard program, which переконфигурируется depending on specifics of concrete system (certainly if memory of all components of 1-Wire-system is filled according to the certain, in advance stipulated rules). If in the course of work of system it is required to store additional volumes of information, at the disposal of the developer there are the special single-wire devices containing both constant (DS2502/DS2505/DS2506), and non-volatile (DS2430A/DS2432/DS2433) memory of various volumes.

  A number of components of iButton family in MicroCAN cases also can be used as a part of 1-Wire-networks as conducted single-wire devices which solve specific problems of identification, accumulation, storage and information transfer. For example, for realization of procedure of identification in systems of industrial automation there is enough application of widespread nosimy electronic labels of DS1990A. And multipoint temperature monitoring can be easily executed by a network from several devices DS1921# or otherwise devices ТЕРМОХРОН, each of which registers the temperature values measured through certain, in advance set, periods and keeps received information in own non-volatile memory, in essence, being programmed by "the temperature tape recorder". For a solution of the problem of transfer of the data which have been saved up by independent 1-Wire-system, to the personal computer various iButton devices which in this case play a role, so-called, "transport tablets" are issued. The devices of non-volatile memory including in structure of the design a lithium element of a food, first of all, belong to similar devices. It is a number of "tablets" since DS1992 (1Кбит) to DS1996 (64Кбита), and among them, of course, DS1994 updating (4Кбита), containing in addition the knot of a real time clock convenient for generation of temporary labels of kept data or for the organization of independent logger of a resource.

  Besides, for the same purposes devices with electricly erased memory of the EEPROM type of updatings of DS1971 (32байта), DS1973 (512байт) and DS1977 (32Кбайта) can be used. When moving big arrays of information "the transport tablet" is convenient for using together with the adapter of USB port of the DS9490B type which provides high speed of transfer at data exchange between the iButton device and the personal computer. If it is a question only of the solution of a problem of accumulation and data storage in a 1-Wire-network, any of listed above "transport tablets" can be easily included in structure of a similar network. Thus for connection of devices in MicroCAN cases to conductors of the single-wire line use special latches of the DS9100 or DS9098P type, or simpler clips of the DS9094 type.

  From the point of view of skhemotekhnichesky realization of the single-wire interface and stability of work on problem lines all conducted single-wire components historically differ from each other, sharing thus on groups:
  1. DS2401, DS2405 - the first devices with the 1-Wire-interface in plastic cases, are completely similar on circuitry to the first models of iButton devices which were focused for work on short tires (till 1994),
  2. DS1820, DS2407P, DS2450, DS2404, DS2415, DS2417, DS1920 etc. - the second version which has been specially focused for work on long lines (till 2000 now these components are generally laid off), 3. DS18S20, DS18B20, DS1822, DS2438, DS2406P, DS2409, DS2890, DS1973 etc. - the third option steadier against collisions on the 1-Wire-highway in comparison with previous (since 2000),
  4. DS2411, DS2408, DS1921#, DS1977 etc. - the last option, the most successful on reliability of circuitry of the 1-Wire-interface (c of 2003). />/>/>

  the Communication line and topology

  the Big role at creation of 1-Wire-networks plays execution of the single-wire communication line. As a rule, such lines have the structure consisting of three main conductors: DATA - the tire of data, RET - a returnable or earth wire, EXT_POWER - an external food not only served conducted devices, but also external concerning them chains of sensors and governing bodies. Depending on a way of laying, interface to conducted devices and materials used at laying, according to below following Table distinguish three main options of quality of the organization of 1-Wire-networks, each of which means use of special technology and accessories at line realization.

  IEEE1394 (Firewire)

  line Classification	Length of the line	Number of conducted devices	Type of a used cable	Topology	the Master of the line
  Short lines	To 30м	To 50шт.	4-хпроводный telephone	Free	the Passive tightening (resistor)
  Average lines	To 100м	To 200шт.	Twisted pair of 5 categories	the General tire	the Active tightening (DS2480, DS2490 or the special circuit decision)
  Long lines	To 300м	To 300шт.		the General tire with a uniform trunk	the Active tightening taking into account a current in the line

  is frequent at the organization of difficult single-wire networks, for the purpose of convenience of conducting of the communication line, reduction of its extent or decrease in electric load of lines thanks to reduction of devices at the same time working at it, it is necessary to provide the treelike or beam structure of the highway considerably different from structure of the general tire. For this purpose use branchings of 1-Wire-networks of one or several levels. A basic element at creation of such branches is or a usual addressed key of the DS2406 type which provides branching thanks to switching of a returnable wire of the single-wire line, or the specialized vetvitel of DS2409 switching directly the tire of data of the 1-Wire-line. The last option is more preferable since components on the disconnected branch conducted by a vetvitel, remain always in an active condition. Serial service by the master of a network of each of branches, at disconnected other branches, allows to increase considerably total length of the line and number of conducted devices on it.

  If the 1-Wire-system organization on the basis of the personal computer is connected by p with special difficulties, use of the intellectual adapter for LINK type COM port is most optimum. It is realized on the basis of the microprocessor. Thus, the device, completely emulating from a serial port operation of the popular DS9097U adapter, production Dallas Semiconductor Corp., and thus supporting all software developed earlier for personal computers, thanks to built-in own intellectual resources realizes a preferential operating mode of single-wire devices on problem 1-Wire-lines in the conditions of a difficult pomekhovy situation. LINK repeatedly improves the mechanism of an active tightening on lines that allows to receive really ideal signals of an exchange at lengths of a cable more than 300 meters and number of accompanied single-wire components bigger 100шт, and use by the processor of the device of algorithms of a digital filtration repeatedly improves stability of the served single-wire line to electromagnetic hindrances. to Application

  to

  as the international standard and gravity of the relation to this interface from venerable developers and producers of electronics tell to p the numerous facts About recognition of the single-wire tire. For example, there is practically no universal microcontroller, in literature on which application ways of the organization on its base of the master of the single-wire line would not be discussed.

  The line on use of technology of 1-Wire-networks in the field of automation the American firm Embedded Data Systems, LLC (the successor of PointSix, Inc most consistently defends.) . It is possible to tell that this campaign made a name on introduction and promotion of achievements of the single-wire tire in the field of automation. And it, despite that the main area of its activity is not automation of greenhouses and not creation of systems of the fire alarm system, and development of means and systems for service of high-technology industries of mechanical engineering and the chemical industry, and even creation of the unique experimental and scientific equipment. As confirmation it is served by the widest range of production which is issued firm (various probes for measurement of high and low temperatures, sensors of humidity, pressure and acidity with the special functions, special optical sensors, payments of collection of information, the device of interface to the various analytical equipment and many other things), and each of devices contains elements of single-wire technology.

  To perspective examples in a 1-Wire-technology scope for automation, undoubtedly, it is possible to refer activity of such known global manufacturers as SYSTRONIX or AAG Electronica. LLC. Lines of the finished tools, and also numerous examples of their use, and a high rating of sales of delivered products, allow to speak about success and a demand of the concept of the single-wire tire applied by these firms for the solution of the most various problems of the distributed automation.

  Other example which is visually showing in practice of possibility of technology of the single-wire tire, the project of creation of completely automatic meteorological stations (1-Wire Weather Station) which was developed in common by firms PointSix, Inc is., AAG Electronica LLC, Dallas Semiconductor Corp. and Texas Weather Instruments, Inc. In the beginning (still in the mid-nineties) some experimental systems constructed on the basis of the leading personal computer with the DS9097U adapter which is complex heart, from three DS18S20 thermometers which are carrying out control of temperature, DS2438 chip for service of the sensor of humidity of air, the DS2423 component for determination of speed of a wind and 16 electronic labels of DS2401 defining its direction were created. These first meteosystems were established and successfully tested in the course of long operation in the State of Texas. And separate from them were completed with additional single-wire decisions which provided control of signals from sensors: barometric pressure, categories of a lightning, an amount of precipitation upon surfaces, solar activity, humidity of the soil etc. Data from all sensors, registered by each of similar systems, arrived in the personal computer and on the Internet were broadcast in real time on the central operator panel where reception and archiving of data on the region weather, received thanks to information analysis from several territorially dispersed stations was carried out. After a successful conclusion of the Texas Weather Instruments Inc project. for several years successfully trades in the ready completely automatic meteorological stations which are not demanding service by the person. And popularity of similar devices is so great worldwide that Dallas Semiconductor Corp firm. was compelled to begin production of a specialized set of chips of WS-1 which includes the set of single-wire components which is minimum necessary for creation of similar station. And the full complete set of similar systems for numerous users from all over the world, including payments for the independent assembly, the certificated mechanical and constructional elements, is carried out by AAG Electronica LLC firm.

  Quite perspective area in which advantages of technology of 1-Wire-networks and which, especially a lot of attention is given by Dallas Semiconductor Corp campaign are fully used. management of independent chemical sources of a current - storage batteries is. As management here it is understood, - first of all, strict and complete identification of power sources, preservation in memory of each separate electronic device of features of its manufacturing built in the battery and the individual technical characteristics, the most complete monitoring of their key operational parameters throughout all service life, and also formation of the correct managing director of the influence connected with restoration of a charge of a served independent power source. The choice of algorithm of its repeated charge that is directly connected with efficiency of use and service life of many types of accumulators in many respects depends on the correct management and knowledge of history of operation of the battery. For this purpose each of batteries of multielement power designs (especially for mobile devices and means of an uninterrupted food) is supplied with an individual single-wire component, turning in essence into an intellectual system element of an independent food. A number of the chips which are let out by firm, is connected with this direction. Dallas Semiconductor Corp. today dominates in the market of intellectual systems of service of independent power supplies, professing thus a new comprehensive network approach to a problem of management of power elements. Thus, 1-Wire-solutions, allowing to organize the multipoint tire of service of devices of management and management of a charge that gives the chance to accompany not only separate power sources, but also the whole batteries made of a set of separate similar elements are used. Moreover, similar devices are capable to provide not only identification or the simplest temperature control of accumulators, but also full-scale monitoring of their key parameters (tension, a current, the category, "short circuit" control etc.) throughout all time of operation. The results which have been saved up by such devices, remain in the built-in non-volatile memory or in the form of the histogram (DS2436), or in the form of the massif of consecutive counting "adhered" to temporary labels (DS2438).

  Now Dallas Semiconductor Corp campaign. lets out a number precision crystals for monitoring, management, protection and management of restoration of a charge of independent power supplies of the most various types and appointments (DS2720, DS2740, DS2751, DS2770 etc.) . To them, including, family crystals DS276# which unlike other updatings of the similar devices demanding an external binding with use of precision and stable passive components, provide higher precision at control of the current spent by the controllable battery belong. It is reached, including, at the expense of the built-in calibrated resistive circuit (shunt) executed on special semi-conductor technology, and also thanks to existence as a part of similar devices of the special hardware-software mechanism of preliminary calibration.

  of Restriction and interface to industrial networks

  is unconditional, 1-Wire-networks have the niche for application at creation of systems of automation. It is senseless to use seriously them for transfer of big arrays of information, at construction, for example, systems of video surveillance or the high-speed exchange, the fast processes connected with service or to compare possibilities of single-wire networks to such powerful network industrial interfaces, as ProfiBus, FeldBus, LonWorks, CAN, Industrial Internet etc. It is possible even to formulate the main today restrictions for application of systems on the basis of single-wire 1-Wire-networks in the field of automation:

  • need of continuous temporary synchronization or synchronous operation of separate devices for a network (this problem can be solved by input in structure of the tire of a network of the additional line for a signal transmission of the general synchronization),
  • low speed of exchange of information, and as a result impossibility of high dynamics at service of fast processes in real time (if controllable fast process is rather short, the local microcontroller as a part of the single-wire tire can serve it, having kept resultants this in buffer memory, and then to carry out their transfer directly to the master),
  • complexity in realization of a multimasterny operating mode of a network (the specialized vetvitel of the DS2409 1-Wire-networks resolves a problem of the conflicts between several leaders on one single-wire tire).

  Apparently from remarks given in brackets, even these obvious to 1-Wire-networks, difficulties are not insuperable. Moreover, there are the approaches allowing organically to integrate slow of single-wire territorially dispersed structures in structure of such productive networks as CAN and Industrial Internet. It is achievable thanks to application of the special hardware-software decisions realized on the basis of modern microcontrollers, and as unique instrument of campaign of Dallas Semiconductor Corp. - TINI devices (Tiny InterNet Interface ).

  of TINI400 is the whole microsystem which basis is the central processor realized on the high-efficiency network DS80С400 microcontroller which unites resources of a number of the most widespread network interfaces, somehow: RS232, 1-Wire, CAN 2.0B, Ethernet, without speaking about possibility of use of the parallel shestnadtsatirazryadny synchronous highway, and also independent knots for the organization of standard local consecutive I2C and SPI interfaces. Besides, the payment of TINI400 contains 1Мбайт program Flash-memory, 1Мбайт the static RAM, knot of a real time clock, the lithium battery and silicon identification number. TINI400 under control of a powerful operational environment which includes support of TCP/IP and the virtual Java car which is carefully fulfilled and tested for the TINI models of the previous generation - TINI390 payment works. The last is defined by that fact that the technology of program support for TINI390 for several years developed experts of Dallas Semiconductor Corp. together with the staff of the company Sun Microsystems, Inc., being thus completely open project. Such approach allowed to have the most effective feedback with end users that helped to reveal and eliminate the majority of shortcomings of the software. And now on a site Dallas Semiconductor Corp. it is possible to find all necessary documentation and software development tools that considerably facilitates construction on the basis of the TINI device of local single-wire systems of remote control and the management, uniting advantages fast and productive, but expensive, and slow, but cheap and effective interfaces.

  In the conclusion is necessary to note once again unconditional efficiency and rationality of use of technology 1-Wire at creation of systems of automation of control and management for the various dispersed equipment when high speed is not required at service, but essential flexibility and expandability is necessary at not high costs of realization.