Topic 4. Basics of user work in the operating environment of a personal computer

4.1. Operating Systems

The operating system is a whole series of control programs that are used as an interface between PC components and provide the most efficient implementation of computer resources. The operating system is the basis of the system program that is loaded when the computer is turned on.

The main functions of the OS include:

▪ Receiving commands or tasks from a PC user;

▪ accepting and applying program requests to start and stop other programs;

▪ Loading programs suitable for execution into the OP;

▪ protecting programs from mutual influence on each other, ensuring data safety, etc.

According to the types of user interface (a set of techniques that ensure the interaction of PC users with its applications), the following operating systems are distinguished:

a) command interface - issuing a system prompt to the monitor screen for entering commands from the keyboard (for example, MS-DOS OS);

b) WIMP interface (or graphical interface - a graphical representation of images that are stored on a hard disk (for example, Windows OS of various versions);

c) SILK interface (Speech Image Language Knowledge) - the use of speech commands for interaction between a PC user and applications. This type of OS is currently under development.

According to the task processing mode, the following operating systems are distinguished:

a) providing a single-program mode, i.e. a method of organizing calculations in which at one time they are able to perform only one task (for example, MS-DOS);

b) working in multiprogram mode, when organizing calculations on a single-processor machine creates the appearance of executing several programs.

The difference between multiprogramming and multitasking modes is that in multiprogramming mode, several applications are executed in parallel, while the user does not need to take care of organizing their work, these functions are taken over by the OS. In multitasking mode, parallel execution and interaction of applications must be provided by application programmers.

In accordance with the support of the multi-user mode, the OS is divided into:

a) single-user (MS-DOS, early versions of Windows and OS / 2);

b) multiuser (network) (Windows NT, Windows 2000, Unix).

The main difference between a multi-user OS and a single-user OS is the availability of means to protect each user's information from illegal access by other users.

4.2. Software classification

Software is a set of programs and related documentation that is designed to solve problems on a PC. It is of two types: systemic and applied.

System software is designed to control a computer, create and support the execution of other user programs, and provide the user with all kinds of services.

Application software is a set of programs that allow you to perform specific operations.

Software is usually divided into operating systems, service systems, software tools and maintenance systems.

The operating system manages the operation of all PC devices and the process of executing application programs and monitors the health of the PC hardware, boot procedure, file system management, user interaction with the PC, loading and executing application programs, allocating PC resources, such as RAM, CPU time and peripherals between application programs.

Currently, instead of the OS of the DOS family, the OS of the new generation is used, the main distinguishing features of which are:

▪ multitasking - the ability to ensure the execution of several programs simultaneously;

▪ developed graphical interface;

▪ use of microprocessors;

▪ stability in work and security;

▪ absolute independence from equipment;

▪ compatibility with all types of applications developed for MS DOS.

Service systems provide the OS with more opportunities and provide the user with a set of various additional services. This type of system includes shells, utilities, and operating environments.

An OS shell is a software product that makes the user's communication with the computer more comfortable.

Utilities are utility programs that provide the user with some additional services,

The disk check program is designed to check the correctness of the information contained in the disk file allocation tables and search for bad disk blocks.

A disk compactor (or disk defragmenter) is used to create and maintain compressed disks. A compacted disk is a file on a conventional physical floppy or hard disk that is compressed when written and recompressed when read.

The disk backup program is designed to work in three modes: backup, recovery and comparison of source data with their backups.

Archivers include programs that can significantly reduce the "volume" occupied by a particular document. Archivers are used to save memory space.

The System Monitor program is used to analyze the peak usage of the processor and other resources.

Antivirus programs are integrated tools for detecting and eliminating computer viruses.

Software tools are software products used to develop software.

Maintenance programs are used to control the operation of various computer systems, allow you to monitor the correct functioning of it, as well as perform diagnostics.

4.3. Purpose of operating systems

The appearance of the computer system depends on the type of OS, consisting of processors, memory, timers, various types of disks, magnetic tape drives, printers, network communication equipment, etc. The operating system is used to manage all the resources of the computer, ensuring maximum efficiency of its functioning. The main function of the OS is the distribution of processors, memory, other devices and data between computing processes that compete for these resources. Resource management includes the following tasks:

1) resource planning, i.e. determining to whom, when and in what quantity it is necessary to allocate this resource;

2) control over the state of the resource, i.e. maintaining operational information about whether the resource is occupied or not, how much of the resource has already been distributed, and how much is free.

Operating systems are classified according to the features of the implementation of computer resource management algorithms, areas of use, and many other features.

4.4. Evolution and characteristics of operating systems

Tube computing devices were created in the mid-1940s. At that time, the OS was not used, all tasks were solved manually by the programmer using the control panel.

In the mid 1950s. semiconductor elements were invented and began to be used, in connection with this, the first algorithmic languages ​​\uXNUMXb\uXNUMXband the first system programs - compilers, and then the first batch processing systems appeared. These systems became the prototype of modern operating systems and were the first system programs for managing the computing process.

The period from 1965 to 1980 saw a transition to integrated circuits.

The advent of LSI led to a sharp reduction in the cost of microcircuits. The computer became available to an individual, which led to the onset of the era of the PC.

For the mid 1980s. characterized by the development of PC networks running networked or distributed operating systems.

The operating system is the main part of the network software, it provides the environment for applications to run and determines how efficiently they will work. The main requirement for modern operating systems is the ability to perform fundamental functions, in particular, efficient resource management and provide a convenient interface for the user and application programs. The operating system is designed to implement multiprogram processing, virtual memory, support a multi-window interface, etc. In addition to functional, market requirements are also imposed on the OS.

1. Extensibility. The system should be written in such a way that it can be easily added and changed without violating its integrity.

2. Portability. Without much difficulty, the OS should be ported from one type of hardware to another type of hardware.

3. Reliability and fault tolerance. The operating system must be protected from internal and external errors, failures and failures; its actions should be predictable, and applications should not destroy it.

4. Compatibility. The system must have the means to run application programs written for other operating systems. The user interface of the system must be compatible with existing systems and standards.

5. Safety. The system must have means of protecting the resources of some users from others.

6. Performance. The system should be as fast as the hardware allows.

The network OS is evaluated according to the following criteria:

▪ the ability to share files and printers with high performance;

▪ effective execution of application programs oriented to the client-server architecture, including application programs from manufacturers;

▪ availability of conditions for working on various platforms and with various network equipment;

▪ ensuring integration with the Internet, i.e. support for relevant protocols and Web server software;

▪ remote network access;

▪ organization of internal email, teleconferences;

▪ access to resources across geographically dispersed, multi-server networks using directory and naming services.

4.5. Operating system of new technologies

An example of a new operating system is Microsoft Windows NT, which is a fast 32-bit networking system with a graphical user interface and built-in networking tools. This OS is network oriented.

In order to communicate between remote sites using a remote access service, modems are required at both ends of the connection, printers, tape drives, and other devices.

The Windows NT operating system has the features listed below.

1. Portability, i.e. the ability to work on CISC and RISC processors.

2. Multitasking, i.e. the ability to use one processor to run multiple applications or threads.

3. Multiprocessing, which includes multiple processors capable of simultaneously executing multiple threads, one for each processor in the computer.

4. Scalability, i.e. the ability to automatically use the positive qualities of the added processors. For example, to speed up the application, the OS can automatically connect additional identical processors. Windows NT scalability is provided by:

▪ multiprocessing of local computers, i.e. the presence of several processors, interaction between which occurs through shared memory;

▪ symmetric multiprocessing, which involves simultaneous execution of applications on several processors;

▪ distributed information processing between several networked computers, implemented based on the concept of remote procedure calls, which supports the client-server architecture.

5. Client-server architecture that connects a single-user workstation and multi-user general-purpose servers (to distribute the data processing load between them). This interaction is object-oriented; the object sending the message is the client, and the object receiving the message is the server.

6. Object architecture. Objects are directory, process and thread objects, memory section and segment objects, port objects. An object type includes a data type, a set of attributes, and a list of operations that can be performed on it. Objects can be managed using OS processes, i.e., through a certain sequence of actions that define the corresponding program and make up the task.

7. Extensibility, which is due to an open modular architecture that allows you to add new modules to all levels of the OS. The modular architecture facilitates connectivity with other networking products, and computers running Windows NT are able to interact with servers and clients from other operating systems.

8. Reliability and fault tolerance, determined by the fact that the architecture protects the OS and applications from destruction.

9. Compatibility, i.e. the ability of Windows NT version 4 to support MS DOS, Windows 3.x, OS/2 applications and have a wide range of devices and networks.

10. Domain architecture of networks, which predetermines the grouping of computers into domains.

11. A multi-level security system that was created to ensure the security of the OS, applications, information from destruction, illegal access, unprofessional user actions. It works at the level of the user, local and network computers, domains, objects, resources, network transmission of information, applications, etc.

4.6. WINDOWS NT architecture

The Windows NT operating system has a modular architecture.

The first module - user mode - allows the user to interact with the system. This level includes environmental subsystems and a security subsystem. A set of instrumental subsystems that support different types of user programs is called an environment subsystem. These subsystems include NT-32, which supports 16- and 32-bit Windows and DOS applications, a subsystem that controls the Windows NT user interface, and others. The security subsystem provides legal user login to the system.

The second module - kernel mode - ensures the safe execution of user applications. At this level, three enlarged modules are distinguished: executing services, the kernel, and the level of hardware abstractions.

The interaction between the subsystem core and environment subsystems is carried out by executing services consisting of a system service and a kernel mode service. A system service is an interface between application environment subsystems and kernel-mode services. The kernel-mode service consists of the following software modules:

▪ input/output manager, which allows you to manage information input/output processes;

▪ object manager, which manages system operations that are performed on objects (use, rename, delete, protect an object);

▪ security control manager, which guarantees the security of the system;

▪ means of calling local procedures that support the operation of user applications and environment subsystems and ensure the exchange of information;

▪ virtual memory manager, which is a service that manages physical and virtual memory;

▪ process manager, which regulates the actions of processes (creation, deletion, logging); distributing address space and other resources between processes.

All system processes are controlled by the Windows NT kernel, which is also responsible for the optimal operation of the system.

The part of the system that ensures the independence of the upper levels of the OS from the specifics and differences of specific hardware is called the hardware abstraction layer. This module contains all hardware-specific information.

The graphical user interface is designed to create a comfortable environment for the user when working with Windows NT. This interface is clear, simple, convenient when launching programs, opening and saving files, working with files, disks and network servers. The GUI in Windows NT is based on an object-oriented approach. The work of the user in this approach is focused mainly on documents, and not on programs. Loading any document is carried out by opening the file that contains this document, while automatically loading the program with which the file being opened was created.

The Windows NT user interface contains the following elements: "Desktop"; "Task bar"; "Start menu"; "Context menu"; "Windows NT application menu system"; shortcuts: "My Computer", "Network Places", "Recycle Bin", "Internet Explorer", "Inbox", "Portfolio"; "Window"; "Fonts"; "Windows NT Help System". The desktop includes shortcuts depicting programs, documents, and devices. Shortcuts allow you to quickly access programs, folders, documents, devices on your computer or network.

4.7. WINDOWS NT installation

The installation is designed to resolve issues in the sequence below.

1. Selecting the file system to be used. If you are installing Windows NT Server, you must decide whether to use the domain model or the workgroup model. During installation, you need to specify the role played by the Windows NT Server machine: primary or backup domain controller, file server, printer, or application server.

2. Formation of a set of required protocols installed by default. If you select the Express Setup installation type, you can install other protocols later.

3. Preparation of a given password.

4. Selecting the type of network card used, the type of disk adapter, the configuration of the sound card.

5. Determining the type and model of the printer and the port of its connection while installing Windows NT and printer drivers.

6. Testing equipment for serviceability using diagnostic tests.

7. Checking the compatibility of all computer devices with Windows NT

During the installation of a Windows NT system, the installation program prompts you for the installation options you want to install on your hard drive, then copies the files that you use, creates, and displays a start menu.

Windows NT installation can be:

▪ initial, if no system was previously installed on the computer or the existing OS needs to be completely replaced;

▪ upgradable, when Windows NT is installed over a previous version while preserving the existing OS. This replaces all existing Windows NT files and preserves the registry settings, the data of which is associated with application loading and security identifiers.

Windows NT installation begins by launching the winnt.exe utility, which is a 16-bit application that runs in DOS, Windows NT, etc. In case of an update, the 32-bit version of this file, winnt32.exe, is launched.

There are several ways to install Windows NT:

▪ from an HCL-compatible CD-ROM using boot disks;

▪ CD, if there is an OS without using boot disks;

▪ a storage device that is accessible on the local computer network.

If the CD-ROM is an HCL-compliant device, Windows NT is installed using boot diskettes.

When the computer has a previously installed OS and the CD-ROM is not an HCL-compliant device, the contents of the corresponding folder are copied to the hard disk. Using the key, the installer copies files to the hard disk from any other medium, except for bootable disks. These files will be launched after the computer is restarted.

With the support of a network card and Windows NT network protocols, it is possible to run the installation program without using additional keys. The files and distribution directories can be located on the server's CD-ROM or hard drive. If the network card or protocol is not supported by Windows NT, then the entire distribution directory should be copied to the computer's hard drive.

If any of the OS was not previously installed on the computer, then a boot disk for the user can be created using the Windows NT Server Client Administrator Utility. This disk initiates the DOS boot, and it becomes possible to copy the distribution files to the disk.

4.8. Registry and configuration of the WINDOWS NT operating system

The main information about the composition of the Windows NT system is located in the registry (a special database), which contains information about: installed programs, libraries and drivers; about links between documents and programs in which they were formed; parameters that control the operation of computers connected to local or global networks.

When using the registry, it is possible to modify the OS configuration. The same result can be obtained using the user interface, for example through the control panel. The registry reflects all changes, but before making changes to it, you should make a backup copy of the system and print its main elements. The registry can be edited by a user registered in the Administrator group.

Information about the local system is located in the following subsections:

1) SYSTEM (system) - information related to starting the system, loading device drivers;

2) Hardware (hardware) - information about installed hardware, displays their current state;

3) Software (software) - information about software settings;

4) Security Account Manager SAM (security account manager) - information about the local user, group accounts and domain value;

5) SECURITY - information about the protection used by the security system of this computer.

With this architecture of the registry, it becomes possible for Windows NT to maintain a universal store for all information and provide distributed but secure access to it over the network. The total size of Windows NT 4 registry files is limited to 2 GB or unallocated disk space on the system volume. The ability to replace the characteristics and values ​​of subsections and registry keys allows you to change the Windows NT OS, in particular:

▪ increase the speed of the desktop by setting the number of icons stored in memory and the cache file;

▪ Vary the number, size and color of icons that are displayed on the screen, and other OS shell settings;

▪ replace Windows Explorer with a program manager or another shell;

▪ change the appearance of standard icons on the desktop and in the start menu.

To select a different type of system service, device driver, or file driver, you must set the desired options in the appropriate registry key.

The registry allows you to increase the efficiency of working with memory, namely, to improve the use of physical and virtual memory in Windows NT. This can be done by increasing the size of the file cache.

Using the registry helps you manage many networking components, but not all networking services may run on your system. Using utilities, you can identify active components and place them at the top of the list of network access components, which will lead to a significant increase in system performance. The same program determines the level of occupancy of the OP, and if there is not enough memory, it can change the number of users accessing the server.

With a large number of requests, it is possible to change the number of threads. Increasing this value improves system performance.

Utilities and appropriate protocols are used to install and configure remote access. The same utility is used to configure port usage.

4.9. Features of the WINDOWS 2000 operating system

The Windows 2000 software product can be used in desktop PCs and server clusters with symmetric multiprocessing. The process of such processing is supported by a storage subsystem with a capacity of millions of terabytes, and an RAM with a capacity of hundreds of gigabytes. The Windows 2000 operating system includes four network operating systems that are focused on solving various types of user tasks:

1) Windows 2000 Professional - a network OS designed for office and mobile PCs. This system is an improved version of Windows NT Workstation 4.0 and has increased reliability and security;

2) Windows 2000 Server is a universal network operating system supported by 4-processor servers and 4 GB of RAM, aimed at small and medium-sized organizations. Windows 2000 Server takes the best features of Windows 2000 Server 4.0 and sets a new standard for reliability, OS integration, directory services, applications, Internet networking, print services, and file access;

3) Windows 2000 Advanced Server is a specialized OS supported by 8-processor servers and 8 GB RAM. Used to work as an application server, Internet gateway, etc.;

4) Windows 2000 Datacenter Server - a system that supports 32-processor architectures and 64 GB RAM. Used to solve resource-intensive tasks, it is able to solve all the tasks of Windows 2000 Advanced Server and problems that require a high level of scalability.

The scalability and performance of the Windows 2000 system is great compared to the rest, which is achieved due to the expansion of the physical address space, which allows the processor to address 64 GB of RAM; support for 32-processor systems; the use of special software settings when reserving and blocking memory, which reduce the competition between processors for resources, etc.

Windows 2000 is enhanced with tools such as Advanced System Restore, Driver Incompatibility Repair Wizard, and Component Manager to make the administrator's job easier and more secure.

The principle of reducing the time of unplanned downtime of the system to zero, in case of their occurrence, i.e., maximum assistance to the administrator in identifying these causes, is implemented in Windows 2000. For this purpose, mechanisms for increasing reliability are built into the system and administrators are given new tools to restore the system in case of failures .

If the failure is caused by the installation of incorrect drivers, then the administrator must boot in safe mode, that is, select one of four possible boot modes: standard, network, command line, or restore active directory service.

In safe mode, the administrator can verify the correctness of any drivers, and he can change the default values ​​of driver and service key parameters in the configuration registry branches that define them.

Another system recovery tool is the recovery console, used when booting from a CD or boot floppies to restore the system or replace corrupted system kernel files.

4.10. Network operating systems

The network operating system (Network Operation System - NOS) is a set of operating systems of individual computers that contact each other in order to exchange information and share resources according to uniform rules (protocols). In addition, such a system is the OS of a separate workstation, which provides it with networking.

The network OS contains the following tools:

1) management of local PC resources (for example, distribution of OP between running processes);

2) provision of own resources and services for general use (server part of the OS);

3) requesting access to remote resources and services, as well as their use (the client part of the OS);

4) messaging in the network (communication means).

Any network OS must manage resources efficiently, provide a convenient multi-window user interface, etc. Since the 1990s. Some standard requirements began to be imposed on network operating systems:

▪ ability to expand;

▪ portability;

▪ sufficient reliability;

▪ compatibility;

▪ security;

▪ productivity.

Depending on the functions assigned to network operating systems, they are divided into systems designed specifically for peer-to-peer networks and systems for networks with a dedicated server. Server computers should use operating systems that are optimized for certain server functions. Therefore, in networks with dedicated servers, network systems are often used, which consist of several OS options that differ in the capabilities of the server parts.

According to the scale of networks served, network operating systems are divided into the following types:

1) networks of departments that form a small group of employees of a particular enterprise or organization. The main task of such a system is the process of sharing local resources;

2) campus-level networks, which combine several networks of enterprise departments within a separate building or one territory into a single local area network. The main function of such systems is to provide access to employees of some departments to information and resources of networks of other departments;

3) corporate networks (or enterprise networks), which include all local networks of an individual enterprise located in different territories. Corporate networks are global computer networks. Operating systems at this level must support a wider set of services.

4.11. UNIX family of operating systems

The UNIX (Uniplex Information and Computing Services) system project was created by K. Thompson and D. Ritchie at AT&T's Bell Labs more than 20 years ago. The OS they developed was implemented in assembler. Initially, Bell Labs employee B. Kernigan called this system "UNICS". However, it soon became known as "UNIX" for short.

In 1973, D. Ritchie developed the C (C) high-level programming language, and UNIX was soon rewritten in this language. After the publication of D. Ritchie and K. Thompson in 1974 in the journal CACM, the UNIX system began to be used everywhere.

The main problem of the UNIX family OS is the incompatibility of different versions. Attempts to standardize versions of UNIX ended in failure, as two incompatible versions of this system were most widely used: the AT & T line - UNIX System V and the Berkeley line - UNIX BSD. Many companies based on these versions developed their own versions of UNIX: SunO- and Solaris from Sun Microsystems, AIX from IBM, UnixWare from Novell, etc.

One of the latest versions of UNIX System V Release 4 brought together the best features of the UNIX System V and UNIX BSD lines, but this version of the system is incomplete, as it lacks the system utilities necessary for successful use of the OS.

Common features for any UNIX OS are:

1) multi-user mode with a method of protecting data from unauthorized access;

2) implementation of multiprogram processing in the time-sharing mode, which is based on the use of preemptive multitasking algorithms; increasing the level of multiprogramming;

3) unification of input-output operations based on the extended use of the concept of "file";

4) a hierarchical file system that forms a single directory tree regardless of the number of physical devices used to place files;

5) portability of the system, which is carried out by writing its main part in the C language;

6) various means of interaction between processes, for example, through a network;

7) disk caching to reduce the average file access time.

4.12. Operating system Linux

The Linux OS is based on the project of L. Torvald, a student at the University of Helsinki, which uses the Minix program. L. Thorvald developed an efficient PC version of UNIX for Minix users and called it Linux. In 1999, he released version 0.11 of Linux, which went viral on the Internet. In subsequent years, this OS was finalized by other programmers who put into it the features and features inherent in standard UNIX systems. After some time, Linux became one of the most popular UNIX projects of the late XNUMXth century.

The main advantage of the Linux OS is that it can be used on computers of any configuration - from desktop to powerful multiprocessor servers. This system is able to perform many of the functions traditional for DOS and Windows, such as file management, program management, user interaction, etc. The Linux system is especially powerful and flexible, giving the computer the speed and efficiency of UNIX, while using all advantages of modern PCs. At the same time, Linux (like all versions of UNIX) is a multi-user and multi-tasking operating system.

The Linux operating system has become available to everyone, as it is a non-commercial project and, unlike UNIX, is distributed to users free of charge under the Free Software Foundation. For this reason, this OS is often not considered professional. In fact, it can be described as a desktop version of the professional UNIX operating system. The advantage of the UNIX operating system is that its development and subsequent development took place simultaneously with the revolution in computing and communications, which has been going on for several decades. Completely new technologies were created on the basis of UNIX. By itself, UNIX is built so that it can be modified to produce different versions. Therefore, there are many different official variants of UNIX, as well as versions that suit specific tasks. The Linux operating system developed in this context can be considered as another version of UNIX, which was created specifically for the PC.

The Linux operating system has several editions, since each manufacturer completes the system and its software in its own way, releasing after that a package with its own edition of this system. At the same time, various editions may include modified versions of programs and new software.

4.13. Novell family of network operating systems

One of the first firms to produce both hardware and software for local area networks was Novell. At the moment, she is concentrating on LAN software. Novell is best known for its NetWare family of network operating systems, which are focused on networks with dedicated servers.

Novell focused on developing the highly efficient NetWare back end to provide the highest possible speed for remote file access and data security for this class of computer. For the server side of its systems, Novell has developed a specialized OS that is optimized for file operations and uses all the features of Intel x386 and higher processors. There are several stages in the evolution of Novell's network operating systems:

1) 1983 - the first version of NetWare was developed;

2) 1985 - the system Advanced NetWare v 1.0 appeared, expanding the functionality of the server;

3) 1986 - version 2.0 of the Advanced NetWare system, which differs from the previous ones in higher performance and the ability to combine different networks at the link level. This OS provided the ability to connect up to four networks with different topologies to one server;

4) 1988 - OS NetWare v2.15, which added support for Macintosh computers to NetWare;

5) 1989 - the first version of 32-bit OS for servers with 80386 microprocessor - NetWare 386 v3.0;

6) 1993 - OS NetWare v4.0, which became in many respects a revolutionary new product.

Versions of NetWare v4.xx have the following features:

▪ have a specialized network resource management system (NetWare Directory Services - NDS);

▪ memory management is carried out by only one area;

▪ the new Data Storage Management system contains three components: block fragmentation, or breaking data blocks into subblocks (Block Suballocation); file packaging (File Compression); data movement (Data Migration);

▪ include built-in support for the Packet-Burst Migration protocol;

▪ all system messages and interface use a special module;

▪ NetWare v4.xx OS management utilities are supported by DOS, Windows and OS/2 interface.

Flaws in NetWare v4.0x prevented it from winning the market. NetWare v4.1 became more widespread. The NetWare v5.x and NetWare v6 lines evolved from NetWare v4.x.

Author: Kozlova I.S.

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Producing solar energy in space is becoming more feasible with the advent of new technologies and the development of space programs. The head of the startup Virtus Solis shared his vision of using SpaceX's Starship to create orbital power plants capable of powering the Earth. Startup Virtus Solis has unveiled an ambitious project to create orbital power plants using SpaceX's Starship. This idea could significantly change the field of solar energy production, making it more accessible and cheaper. The core of the startup's plan is to reduce the cost of launching satellites into space using Starship. This technological breakthrough is expected to make solar energy production in space more competitive with traditional energy sources. Virtual Solis plans to build large photovoltaic panels in orbit, using Starship to deliver the necessary equipment. However, one of the key challenges ... >>

Random news from the Archive Toshiba TC3567x series chips supporting Bluetooth 4.1 LE 23.07.2016 Toshiba announced the release of TC35678FSG, TC35678FXG and TC35679FSG chips supporting Bluetooth Low Energy (LE) 4.1 wireless interface. According to the manufacturer, they have the lowest energy consumption in their class, consuming half the energy compared to their predecessors. The supply voltage of new microcircuits can lie in the range of 1,68-3,6 V. At a voltage of 3,0 V, the current in transmit mode is 3,6 mA, in receive mode - 3,3 mA, and in sleep mode it does not exceed 100 on the. As stated, a beacon with such a microcircuit can work from one CR2032 element for more than a year. The TC35678FXG and TC35678FSG models feature 256 KB of flash memory. Between themselves, these microcircuits differ in design: TC35678FXG is available in a QFN60 package with dimensions of 7 x 7 mm, which made it possible to increase the number of GPIO lines from 16 to 32, and TC35678FSG - in a QFN40 package with dimensions of 5 x 5 mm. Same package selected for TC35679FSG. Toshiba's new Bluetooth 4.1 LE chips are designed for wearable electronics, medical devices, smartphone accessories, remote controls and toys. Their trial samples are already available. The manufacturer expects to start serial deliveries of TC35678FXG at the end of this year, and deliveries of two other products - at the beginning of 2017.

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