Pocket and notebook personal computers. How to choose a PDA, other characteristics

The basis of the internal structure of most currently sold pocket personal computers (PDAs) is still the Intel PXA250 processor of the Intel XScale microarchitecture. This processor, which has a relatively high clock frequency and data processing speed, together with other components formed the basis of the architecture of many PDA models. It provided broad functionality and high performance of these devices.

In addition, the Intel PXA250 processor was an important step in the evolution of elements of this type. He laid the foundations for the design of the Intel XScale processor models that replaced it and the improved PDA models created on their basis.

The emergence of computing devices became a natural stage in the development of civilization, when it was necessary to process significant flows of information. Moreover, a real breakthrough in this process occurred after the advent of computers aimed at individual work.

Despite the short history of personal computers, today it is difficult to imagine life without these functionally complex devices. Their architecture and operation are based on the latest semiconductor technologies. Thanks to their unique consumer properties and rich functionality, personal computers have become widespread in almost all areas of human activity - from defense, industrial production and business to education, culture and leisure.

However, desktop systems, which are currently the dominant class of computers, for all their advantages, have one fundamental drawback. The fact is that neither the design of these devices, nor the dimensions, nor the weight, nor, of course, the method of power supply allow their mobile use, while the need for portable devices is extremely high.

Indeed, many specialists involved in operational information processing processes, due to production needs, are forced to spend a significant portion of their working time outside their offices, which means that they do not have access to their computers.

One solution for this group of specialists is the use of mobile computers such as laptops. However, with all the variety of capabilities of this class of computers, these devices are not always acceptable. The fact is that, despite the gradual reduction in the size and weight of these computers, in some cases even more compact products are required, characterized not only by significantly less weight, but also by longer battery life.

The optimal solution in such cases, and perhaps the only solution today, may be pocket personal computers (Pocket PC) PDAs, or, as they are commonly called throughout the world, PDA (Personal Digital Assistant). This choice is supported by the fact that, thanks to the successes of modern semiconductor technologies, these ultra-compact computers are gradually becoming full-fledged multimedia devices, capable in some cases of replacing even desktop versions of computer systems. Moreover, recently the architecture of PDAs has begun to be expanded with wireless radio communications, not to mention the fact that the industry produces a wide range of additional devices for this class of computers. They can significantly increase the already extensive functionality of the PDA. To connect these additional tools, it is enough that these devices and PDAs provide support for the relevant standards. This is usually possible due to the presence in the architecture of handheld computers of a large number of integrated controllers implemented in a limited number of semiconductor chips.

Myths and reality

Appreciating the capabilities of pocket personal computers, most potential users often express doubts about the reasonableness of the prices at which these devices are offered by numerous manufacturers.

Indeed, in size and design, many (if not all) PDA variants resemble calculators. The price of a number of models of these ultra-compact computers is often comparable to the cost of the simplest laptops - products that are better known to the general public and, accordingly, more popular in the consumer market. In addition, when analyzing the prospects of certain PDA models, future users also have to take into account the growth in the functionality of mobile phones.

These rapidly developing devices, with the help of built-in hardware and software, in many cases are already capable of performing complex processing of audio and video data with transmission of the results via high-frequency radio channels of standard cellular networks, while maintaining, of course, traditional voice communication functions.

The consequence of this marketing pressure is that many potential PDA users have a number of illusions, the most common of which is that almost all the capabilities of these computers are determined exclusively by the processors used. Moreover, many believe that designing a PDA comes down mainly to ensuring correct I/O signals from the processor used. The consequence of this is the erroneous idea of ​​a PDA as a very simple system consisting of a display, a few switches and external connectors, and perhaps a few additional elements, such as a speaker, microphone, Wi-Fi antenna. As for the large difference between the cost of the final product and the price of the processor, reaching several hundred dollars (which means an increase in price by several tens of times), this injustice lies solely on the conscience of the computer companies that produce and sell such compact computers.

While paying tribute to the creative successes of processor developers for PDAs, it is necessary to emphasize the fallacy of such opinions, as evidenced by the analysis of the elements and structure of one of the PDA models given below. Its architecture, as well as the ideas and technologies implemented in its design, can be considered typical for similar products. The basis of this model is the Intel PXA250 processor.

Intel PXA250 processor

Structure and parameters

The Intel PXA250 processor, developed and manufactured by Intel Corporation, is aimed at the market of pocket personal computers, smartphones, various types of communicators, including devices equipped with wireless communications, as well as embedded data processing systems, etc.

A functional diagram of the Intel PXA250, which describes the structure, integrated elements and controllers included in this processor, is presented in Fig. 1.

The Intel PXA250 processor is based on the 32-bit Intel XScale RISC core, which provides superscalar instruction execution. The structure of this core is based on the Advanced RISC Machines (ARM) architecture. The Intel PXA250 instruction set is compatible with ARM version 5TE ISA (ARM Thumb Instruction Support, ARM DSP Enhanced Instructions). This ensures continuity of software developed for previous processor models of this type, for example, the previously released Intel PXA210 processor.

However, having inherited much from its predecessors, the next processor core from Intel also has some features. Thus, the XScale core of the Intel PXA250 processor has the following characteristics:

32 KB instruction cache;

32 KB data cache;

2 KB mini data cache (separate from L1);

2 KB mini instruction cache (designed for resident debug program);

40-bit accumulator and extended 16-bit multiplier for multimedia processing;

Instruction and data memory management tools, etc.

Along with the Intel XScale core, many technical features are integrated into the processor.

The memory controller built into the Intel PXA250 processor supports a wide range of memory chip types, taking into account their different internal and external organizations: up to four SDRAM memory banks, six static SRAM memory chips, SSRAM, Flash, ROM, SROM, as well as companion chips. In addition, a computer system based on the Intel PXA250 can be equipped with one or two PCMCIA or CompactFlash slots. At the same time, the system memory interface supports: 100 MHz SDRAM, from 4 to 256 MB SDRAM, four 64 MB SDRAM banks.

The built-in liquid crystal display (LCD) controller is capable of working with passive or active LCD panels. This controller provides support for 1, 2, 4-bit gray and 8- or 16-bit color depth. It is possible to work with a 1024x1024 resolution display, but the recommended resolution is up to 800x600 pixels with 16-bit color depth.

An example of connecting computer system components to controllers built into the structure of the Intel PXA250 processor is shown in Fig. 2.

Rice. 2. Example of connecting computer system components to an Intel PXA250 processor

The Intel PXA250 processor supports core clock speeds of 100-400 MHz (for comparison: the maximum clock speed of the previous processor, Intel PXA210, reached 200 MHz). Different operating modes ensure scaling of a computer system based on the Intel PXA250, both in terms of performance, determined by the clock frequency, and in power consumption, depending on the clock frequency and supply voltage. Moreover, the higher the processor supply voltage (of course, within the permissible level), the higher the clock frequency value can be set, and vice versa - the lower the supply voltage, the lower the maximum clock frequency value.

The maximum power consumption of the Intel PXA250 processor is 1.4 W, the minimum is less than 500 mW.

Possible standard electrical and frequency operating modes of the Intel PXA250 processor are given in table. 1.

The embodiment of the developers' architectural plans and the implementation of the processor's wide functionality became possible thanks to the use of a well-developed technological process. The Intel PXA250 processor is created using CMOS technology using 0.18 micron lithography and six metallization layers.

The Intel PXA250 processor chip is packaged in a PBGA package with dimensions of 17×17 mm and contains 256 pins.

It remains to add that the Intel PXA250 processor has become an important stage in the evolution of this class of highly integrated elements. It served as the prototype for subsequent generations of processors created for ultra-compact data processing devices, which include pocket personal computers.

Development prospects

The next model in the Intel XScale microarchitecture product line was the Intel PXA255 processor, the architecture of which uses an internal bus with higher bandwidth compared to its prototype. This provided greater performance to the Intel PXA255 processor, and consequently to the entire computer system created on its basis. Nevertheless, this processor should be considered as an improved modification of its predecessor, which does not require significant redesign of previously released PDA models and platforms originally created for the Intel PXA250. This opens up great opportunities for the speedy release of more advanced products based on existing solutions.

However, paying attention to the evolution of processors of the Intel XScale microarchitecture, it should be noted that even more advanced elements were subsequently released.

And not so long ago it was announced the release of the next generation of Intel XScale microarchitecture processors. This is the Intel PXA27x family of processors (previously codenamed Bulverde), which contains a number of new technologies that meet the needs of mobile phone and PDA users.

This is the first product to integrate Intel Wireless MMX technology, delivering enhanced 3D gaming performance and enhanced video playback with extended battery life. The new chip also features technology similar to that found in Intel mobile processors, Wireless Intel SpeedStep, which enables significant energy savings by intelligently controlling voltage and clock speed.

In addition, Intel has for the first time integrated critical security features into the Intel Wireless Trusted Platform to provide services such as trusted boot, secure storage of private information and cryptographic keys, and support for standard security protocols. To expand the capabilities of phones with built-in cameras and improve the quality of shooting, Intel has developed Intel Quick Capture technology, which allows you to increase image resolution to 4 megapixels or more.

The Intel PXA27x family of processors will be available in a variety of configurations with clock speeds ranging from 312 to 624 MHz and stacked with up to 64 MB of Intel StrataFlash memory.

However, when considering the capabilities of the latest promising lines of Intel XScale microarchitecture processors, it should be noted that, despite all their advantages, they do not determine the market for ultra-compact data processing devices, which include PDAs. This is due to the fact that after the latest processors and associated specifications appear on the market, some time must pass for the development and release of the corresponding end-product models to the market. That is why the vast majority of sold PDA models are based on the Intel PXA250, and only the latest device models, which have not yet received wide distribution, are created on the Intel PXA255.

Intel Corporation specialists, based on the Intel PXA250 processor, have developed the Intel DBPXA250 platform (Intel DBPXA250 Development Platform for Intel Personal Internet Client Architecture), the functional diagram of which is presented in Fig. 3. This development can be considered as a complex multifunctional system with a wide range of uses. Based on the Intel DBPXA250 platform, control systems for various devices, information systems, audio and video data processing centers, as well as wired and wireless data transmission systems can be created. However, first of all, this platform is intended for research purposes and development of hardware and software solutions based on XScale technologies.

Many circuit ideas of the given Intel DBPXA250 platform have been embodied in the architectures of pocket personal computers created by third-party manufacturers.

In Fig. Figure 4 shows the generalized structure of one of the PDA architecture options, which includes several wireless communication subsystems of different types.

Rice. 4. Structure of one of the PDA variants with several wireless communication subsystems

It should be noted that dozens of computer companies are involved in the development and production of PDAs. Next, we will look at a PDA using the example of a specific device Pocket LOOX 600 from Fujitsu Siemens Computers.

PDA device using the example of Pocket LOOX 600

The external view of the Pocket LOOX 600 PDA from Fujitsu Siemens is shown in Fig. 5, and the main parameters of this computer are given in table. 2.

The basis of the architecture of the Pocket LOOX 600 PDA is the relatively powerful Intel PXA250 processor of the Intel XScale microarchitecture, which provides high performance of the entire hardware and software system due to the perfection of the PDA architecture and the high core clock frequency, reaching 400 MHz. In cases where high performance is not required from this compact mobile computer, it is possible to operate the PDA in an economical mode, due to a decrease in the clock frequency, processor supply voltage and its current consumption. The low power consumption technology implemented for this processor by reducing the performance of the PDA significantly increases its battery life.

This mode is set by the user himself in the corresponding menu screens. Further reductions in power consumption can be achieved through the ability to dim the LCD screen brightness, either manually or automatically.

The memory of the Pocket LOOX 600 PDA is represented by two types of elements: RAM (RAM random access memory) and ROM (ROM read-only memory). In this case, the amount of RAM is 64 MB, ROM 32 MB. The large information capacity of the built-in memory allows you to work with a wide range of applications.

A Lithium Polymer battery with a capacity of 1520 mAh, according to the technical documentation supplied with the device, provides 10 hours of operation and 100 hours of standby time. Recharging is possible both through the cradle included in the kit, and by directly connecting the PDA to an external small-sized power supply. At the same time, the computer's energy capabilities are doubled with the use of a second battery, which is not included with the PDA and is purchased separately by the user.

The basis of the system software is the Microsoft Pocket PC 2002 operating system, which includes a quick launch menu for applications FSC SpeedMenu. This allows you to quickly open documents, PDA programs and folders with which you work regularly. If necessary, this version can now be replaced by the more modern Microsoft Pocket PC 2003 system, which provides not only broader functionality of the PDA, but also often, as testing shows, significantly greater performance, as well as stability of operation.

It remains to add that the Bluetooth tools built into the architecture of the Pocket LOOX 600 PDA provide wireless connection and data transmission via radio channel with various devices that have similar tools in their arsenal. This could be, for example, corresponding models of cell phones, mobile computers, and various peripherals.

Features of the internal structure

The structure of Pocket LOOX 600 from Fujitsu Siemens is shown in Fig. 6, and in Fig.

Figures 7-13 show fragments of the PDA design with elements of the architecture of this ultra-compact, multifunctional device for processing multimedia content. In the photographs above you can see the main components and a number of important semiconductor chips, including the Intel PXA250 processor (Fig. 8). At the same time, when assessing the features of the internal structure of a PDA, it is necessary to remember that this Intel XScale processor serves as the basis not only for the described version of a pocket personal computer, but also for many PDA models from other manufacturers. These products are widely represented on the modern computer market, are in demand and enjoy deserved popularity.

Consideration of the architecture of the Pocket LOOX 600 PDA should begin with large semiconductor elements. In Fig. 8 the following microcircuits are clearly visible: to the left of the LCD display connector (central white-yellow connector) there are Sharp LZ9FC22 and Microchip PIC16LF874 microcircuits, and to the right of this connector there is an Intel PXA250 processor and two Intel 28F128J3A150 microcircuits.

Rice. 9. Intel PXA250 processor with passive and active environmental elements

The SHARP LZ9FC22 chip supports the LCD display of the PDA, also manufactured by Sharp. The name of the manufacturer of this display can be found on its edge on the left at the top of the Pocket LOOX 600 PDA (Fig. 7 and 11).

As for the architectural features of the internal design of the Pocket LOOX 600 PDA, it should be noted that for the correct operation of a number of elements, relatively high power supply voltages are required, which pose a danger to traditional semiconductor chips. In order to ensure the safe operation of PDA components and attract the attention of specialists during setup and possible repair of the PDA, electronic elements with increased voltage levels are separated from other components by a special protective plastic film of bright orange color.

Returning to the above list of semiconductor chips, it should be noted that the Microchip PIC16LF874 chip is a very complex microcontroller (CMOS FLASH Microcontroller). This functionally rich element includes a large number of integrated components. The functional complexity of the structure of this Microchip PIC16LF874 microcircuit, which uses a fairly powerful RISC processor (RISC CPU), to some extent changes the view on the architecture of the computer system under consideration and allows us to assert that this Pocket LOOX 600 PDA is, in principle, a multiprocessor system.

The following chips in the mentioned list of relatively large and important semiconductor elements of this ultra-compact mobile computer are called Intel 28F128J3A150. These are Intel StrataFlash memory chips. It is appropriate to recall here that special proprietary technologies implemented in chips of this type of memory, called Intel StrataFlash, provide increased density of programs and data by storing several bits of information in each memory cell.

The MAXIM MAX324xx chip, located next to the multi-position manipulator located at the bottom of the device (see Fig. 5 and 7-11), is an element of the input-output interface of the Pocket LOOX 600 PDA.

At the top of the Pocket LOOX 600 PDA (see Fig. 5 and 7-11) some elements of the system are clearly visible. For example, in the center are a dynamic sound emitter, a stereo headphone jack and computer switch button contacts. On the left side of the PDA there is a scroll wheel, which provides scrolling of displayed texts, and two infrared photodiodes (IR port). And on the right, at the opposite end of the device, there is a Bluetooth wireless interface switch (Fig. 11, 12).

Rice. 12. Reverse side of the Pocket LOOX 600 PDA without the case and with the battery removed

It should be noted that above the liquid crystal panel of the PDA there is a pink wire for the high-voltage power supply of the LCD display, and below this panel you can see a flat multi-wire plastic cable (Fig. 13). By the way, this cable provides an information-logical connection between the display and the electronic components of the system through the previously mentioned connector located in the center of the PDA main board (see Fig. 8).

The Pocket LOOX 600 PDA uses a two-section non-removable (built into the design) SONY FUKUSHIMA lithium-polymer battery with a capacity of 1520 mAh (see Fig. 12 and 13). Here, in Fig. 12, you can see the expansion slots and their contacts built into the PDA design. These slots are used to connect special CompactFlash II and MMC cards. These expansion cards allow you to increase the power of the hardware and software of this small-sized computer system. In particular, using modules made in these standards, you can increase the amount of available memory, which significantly expands the functionality of the PDA. In addition, using the CompactFlash II slot, you can expand the system by connecting additional devices from a wide range of products produced by the computer industry. As an example, we can cite multimedia modules, as well as modules of common wired and wireless communication interfaces that provide connection of PDAs to local and global networks for the purpose of receiving and transmitting various information.

Modularity of the PDA and its possible applications

The connectors built into the PDA allow you to increase the ROM memory capacity and expand the functionality of this small-sized, but productive and functionally rich device by connecting additional modules.

For example, to a PDA equipped with a CompactFlash Type II connector, you can connect a miniature IBM MicroDrive hard drive or similar external memory devices, the capacity of which today already reaches 4 GB, and in the near future it will become even higher.

In addition, it is possible to connect the PDA to a local WLAN network. You can also use LAN network cards; SecureDigital, MultiMedia Card, CompactFlash Type II flash memory cards; PCMCIA port; GPS module, modem, video camera, VGA, TV module and many other modules and cards.

By the way, the GPRS module connected to the PDA, adding the function of a mobile phone to the PDA, turns this ultra-compact computer complex into a very powerful personal communicator. While maintaining the capabilities of a computer and GSM voice communication, this module also allows you to connect to the Internet via standard radio channels of cellular operators.

In addition to GPRS, you can access the Internet via a wireless connection via Wireless LAN, as well as via a GSM mobile phone. In this case, you can use the Bluetooth capabilities of your phone or other devices that provide access to external networks through modems connected to them. However, if necessary, information communication can be realized using traditional IR (IrDA) ports.

A pocket personal computer, given its light weight and size, is convenient to use for reading books in the *.pdf file standard. This is especially true in cases where, for some reason, it is inappropriate to take bulky paper versions with you. When reading text information using a PDA, it is convenient to use the built-in scroll wheel for the image on the screen, which is missing in many similar devices.

The PDA allows you to read and edit documents using Microsoft Word. You can type and edit text on your PDA using handwriting font or its standard equivalent. And using a special keyboard, which is listed in the list of additional accessories, you can work with documents in the usual way.

In addition to the Word editor provided by the Pocket Word version, the Office suite also includes such standard tools as Excel in its Pocket PC version Pocket Excel, as well as a relatively simple calculator supplied as a component of the standard package. In addition, the user has access to notebooks, telephone directories, etc. A useful extension of office functions is the ability to install a set of dictionaries that make it easier to work with texts in foreign languages.

Using multimedia capabilities, you can use your PDA to watch videos and listen to audio recordings. By the way, the PDA can be used as a voice recorder, however, given the relatively low sensitivity of the built-in microphone, it is advisable to record only the user’s voice, and not external sound sources. Recording modes can be selected by varying the number of channels and sampling rate.

Considering the wide functionality of PDAs, it should be noted that pocket personal computers should not be considered an equivalent replacement for laptops or desktop PCs. But they can be considered as a successful addition to them.

Despite the abundance and accessibility of a wide variety of mobile technology, some people still do not know what a PDA is, even if they have a smartphone or other mobile device.

The abbreviation PDA stands for Essentially, the device performs the functions of a regular laptop or laptop, plus it is truly a personal computer, which often cannot be said about its “older” relatives. PDAs differ from them not only in size, but also in power. You also won't be able to freely disassemble it, which is much easier to do with a regular desktop computer.

This is your personal assistant, through which you can read books, view mail, chat with friends, listen to music, write notes. This device is often also called a handheld because it easily fits in the palm of your hand.

At the moment, handhelds are not popular among users, which is why many do not know what a PDA is. The reason for its unpopularity lies in the fact that now many users have smartphones or communicators, which are often the same thing. The former include the functions of a PDA and a mobile phone, while the latter are primarily a mobile phone and a PDA. But the difference is not too big, and therefore these concepts are often used as synonyms.

However, knowing what a PDA is, you will not discount it, because a PDA uses less energy because it does not need to constantly search for a network, which significantly reduces power consumption. It follows from this that handhelds last much longer without charging than communicators, especially those with Android.

So, a pocket personal computer has many functions. The main ones are given below:

1. A device for reading books.
2. Typewriter. Of course, handhelds are small in size, but some of them have a qwerty keyboard, which is very convenient.
3. Music player.
4. Internet.
5. Organizer.
6. There are plenty of games for PDAs, so if you need to kill time, there are many interesting toys to choose from.

These are the most basic functions of a handheld, which are usually used, but there are also plenty of standard programs like a calculator and others. Also, do not forget that a PDA will not replace your desktop computer if you are doing, for example, 3D graphics or want to play a new game that is demanding in terms of system and hardware requirements.

If you are the owner of this device, then you can find everything for your PDA on specialized sites: utilities, games and much more. It should be noted that you will not suffer from a lack of programs designed specifically for handhelds.

In large cities there are even those that sell spare parts for PDAs. If your city doesn’t have this, it doesn’t matter. After all, you can order them in online stores, of which there are many now.

The main advantage of pocket personal computers is their mobility and long battery life, which cannot be said about most smartphones. On the other hand, we must not forget that the little assistant will not replace your desktop computer, which has more functions and more power than a PDA.

A pocket personal computer (PDA, palmtop, palmtop) is the name of a class of mobile digital devices that combine the functions of a computer, telephone, and organizer. In English, the phrases “Pocket PC” and “Palm PC” do not denote the entire class of mobile devices, but are associated with specific brands of PDAs. Since PDAs were originally conceived as electronic organizers, the phrase Personal Digital Assistant (PDA) is used in English to designate the entire class of these devices, and in Russian - PDA.

Unlike laptop computers, most PDAs were designed with the idea that information would be entered into them using a special pen - a stylus, therefore, most PDAs are equipped with the ability to recognize handwritten text. Some PDAs can also respond to voice commands.

The main purpose of a Pocket PC is to serve as a portable electronic organizer that is easy to use and simply connects to a desktop computer to exchange information.

PDAs are improving every year. Modern handhelds can not only store personal information such as contacts, appointments, and to-do lists, but can also connect to the Internet, function as a Global Positioning System (GPS) device, and run multimedia software. Moreover, manufacturers began to combine the functions of PDAs, mobile phones, multimedia players and other electronic devices.

Modern PDAs descend from the first PalmPilot and Microsoft Handheld PC models. Palm models run on the Palm OS operating system, and Microsoft Pocket PC models run on Windows Mobile OS. The difference between these two operating systems is now much smaller than before.

Palm PDA. Most Palm devices are manufactured by palmOne, the maker of the Zire and Tungsten product lines. palmOne was formed in 2003 after the merger of Palm Computing and Handspring.

Characterized by ease of use, Palm OS has:

• · an extensive library of third-party applications (more than 20,000) that can be installed into the system (most Palm PDA models come with a pre-installed set of applications for working with e-mail, software for organizing functions and multimedia programs),
• · updated version of the handwriting recognition program - Graffiti,
• · the ability to synchronize with a desktop computer running both Windows and Mac OS using the Palm Desktop program,
• · smaller Graffiti input area than Pocket PC (higher-end Palm PDAs use a virtual Graffiti area that uses the entire screen area).

Pocket PC

Pocket PC is the generic name for portable Windows Mobile PDA devices. Their standard features include:

• · portable versions of Microsoft applications such as Microsoft Word, Excel, and Outlook,
• · synchronization with Microsoft Outlook,
• · three handwriting recognition programs: Transcriber, Letter Recognizer (similar to the new version of Graffiti), and Block Recognizer (similar to the original version of Graffiti),
• · virtual input area that maximizes screen size,
• · Windows Media Player for multimedia content.

A smartphone is a device that combines the functions of a mobile phone and a PDA. A distinctive feature of smartphones is a more complex operating system, which allows you to install additional software that expands the functions of the device. Devices that combine the functions of a telephone and a computer also include communicators. The communicator is a PDA equipped with GSM communication functions.

This group of devices has the following characteristics:

• o the ability to connect to cellular operators,
• o Internet access via cellular communication,
• o various combinations of functions of phones and PDAs (for example, not all smartphones have a touch screen and the ability to recognize handwritten text),
• o a large number of different operating systems, including Windows Mobile Pocket PC Phone Edition, Palm OS, etc.

Today they can do almost everything that desktop computers and laptops can do, combining these capabilities with the functions of modern mobile phones. In particular, communicators provide GSM mobile communications, perform the functions of a digital camera and video camera and other functions of modern phones. Communicators also perform the function of a GPS navigator. In addition, it is very interesting to use a PDA as a remote control for a wide variety of modern equipment, including TVs, DVD players, media players, etc. The rechargeable batteries currently in use make PDAs truly mobile devices, providing truly long periods of independent operation. And yet, most modern consumers pay primary attention, first of all, to the capabilities of PDAs as computers. In this regard, mobile devices really have something to be proud of. Pocket laptop computers make it possible to watch movies, listen to music, and read e-books. Their users can play the latest computer games. In addition to entertainment functions, communicators allow you to work with office applications. Currently, PDAs have become quite user-friendly devices. The ability to enter and edit data is provided by a number of solutions. In particular, you can use the virtual keyboard displayed on the touch screen. You can enter text directly on the screen using special handwriting recognition programs. Fans of standard methods of working with text can connect a special external keyboard. Some handheld computers come with their own small keyboard. All data and programs from the PDA can be saved on a personal computer via a USB connection. One of the most attractive aspects of PDAs is that they provide the ability to fully work on the Internet, which is especially helpful with Wi-Fi and 3G support. This allows you, from anywhere, to work with email, visit your favorite sites, communicate on social networks, and trade in the stock markets and forex. The hardware capabilities and capabilities of modern operating systems for PDAs make it possible to support all these, and many other, functions at the highest level. As a result, handheld computers today have become not just a type of gadget, but rather a social phenomenon.

If we try to explain in simple words the principles of lending in consumer cooperation, then a suitable analogue would be a mutual aid fund, which works according to a similar system. Indeed, a consumer credit cooperative is a voluntary association of citizens (as well as legal entities) intended to issue loans to needy participants in accordance with the organization’s charter. At the same time, the main source of the formation of the fund are contributions from the shareholders themselves, who receive their share from the general income of the cooperative.

What is a PDA

In order to understand what a credit cooperative is, let’s first look at the legislation, which clearly states that the CCC is a non-profit organization. Such a cooperative is created not to make a profit, but to help its shareholders, who can receive a loan on favorable terms. At the same time, it is beneficial for participants to place their funds in the CPC fund, because the interest will be higher than on a bank deposit.

Loan recipients will not lose either, because they receive finance with less difficulty than with bank lending. If we compare a consumer credit cooperative with a bank, then in the case of a consumer credit cooperative there are much fewer difficulties in obtaining money. For example, the attempts of a novice entrepreneur to obtain a bank loan for business development are largely doomed due to his lack of a large income or credit history. But in such a consumer cooperative, it will be much easier for him to interest him in a successful idea in order to receive financing for his project.

History of cooperatives

Russian credit cooperation originated in 1865, when the first savings and loan partnership was created in the Kostroma province. Further development can be called sustainable - if by the end of the 19th century there were several hundred such associations in the country, then by the revolution their number began to be measured in tens of thousands.

Then - a new society, reforms of Soviet power, the introduction of the New Economic Policy, fierce competition with collective farm principles in the countryside and the growing industrialization of urban life. For a while, CCPs are leaving the Russian scene. After the collapse of the USSR, a renaissance era begins, and at the moment there are more than 3,000 credit consumer cooperatives in Russia.

Operating principles

Any credit consumer cooperative is based on the principle of mutual financial assistance and this is enshrined in law. CPC participants give available funds to needy shareholders for use, making it easier for them to find the necessary finances. At the same time, although share and other contributions are the basis for the formation of a cooperative fund, this is far from the only source of funds. Contributions are made by income from the activities of the credit cooperative, funds raised and other legally permitted methods.

Types of credit unions

Understanding a credit union as an organization that can unite both individuals and legal entities, the legislation establishes both separate types:

• A credit consumer cooperative of citizens, which consists only of individuals.
• Second-level credit consumer cooperative – it can only include legal entities.
• An agricultural credit consumer cooperative, including farms, personal farmsteads, and various agricultural enterprises.

At the same time, the quantitative principle is also important - at least 15 people or 5 organizations can create a CPC for mutual assistance to each other. If we are talking about a mixed form, then at least 7 individuals and legal entities are required. In addition, the law talks about special conditions for state control over the activities of second-tier credit unions and organizations with more than 5,000 members (for example, these may be unscheduled inspections).

Legal regulation in Russia

The legal framework is determined by the Law “On Credit Cooperation” adopted in 2009, which addresses all issues related to the activities of such organizations. Separate chapters are devoted to the nuances of creation and reorganization, membership, management, property, features of raising funds, and other important aspects of the activities of credit cooperatives. The activities of structures in the agricultural sector are regulated by another Law - “On Agricultural Cooperation”, which has been in force since 1995.

How to open a consumer credit cooperative

When planning to create a CPC for mutual financing of shareholders, it is necessary to carefully study the legal basis for such activities. In addition to the legislation on consumer cooperation itself, you need to have at hand the Law “On State Registration of Legal Entities and Individual Entrepreneurs” of 2001, which addresses the requirements for documents submitted for registration. An alternative option may be to contact a law firm, which will take care of all the hassle of registration up to the production of a seal.

Shareholder contributions

A prerequisite for membership in the CPC is the payment of a mandatory share fee (and an entrance fee, if provided for by the organization’s charter). In addition, for shareholders there are:

• Membership fees are intended to cover the costs of maintaining the organization.
• Additional contributions are designed to compensate for unforeseen losses.
• Voluntary contributions - made on an additional basis to shares.

Creation order

Step-by-step instructions for creating a PDA look like this:

1. Prepare all the necessary documentation, hold a constituent meeting where the Charter is approved and governing bodies are elected, and have the application certified by a notary.
2. Submit documents for registration.
3. After completing the registration process, you need to open a bank account, order a stamp and register with extra-budgetary funds.

Before starting activities, it is necessary to implement a system for combating money laundering and the financing of terrorism, for which a special responsible person is appointed in the organization. Such a person must monitor compliance with the “Internal Control Rules”, promptly informing the competent government agencies about suspicious transactions and other transactions with funds and property.

Registration in the state register of SROs

According to current legislation, within three months from the date of creation, the CPC must join a specialized self-regulatory organization (the only exception is second-level cooperatives). Until this time, the cooperative will be very limited in its activities - it cannot accept new members or attract financial resources from shareholders. This is a very important condition, failure to comply with which may lead to the liquidation of the consumer cooperative by decision of the executive authorities.

Credit cooperative funds

Various types of contributions that shareholders make when joining a consumer credit cooperative are intended to support the organization’s activities, and several funds are formed for this task. Although the priority of the CPC is financial mutual assistance to its members, there are other areas that require monetary contributions.

Mutual Financial Assistance Fund

This is the main fund of the consumer cooperative and the main purpose of its creation - loans are allocated from it to needy shareholders. The provision of a loan service involves the conclusion of an agreement between the consumer cooperative and its member (not only an individual, but also a legal entity), and, if necessary, is supported by other documentation. This may be a guarantee or collateral, but much more often such guarantees of the return of funds issued are not required.

Unit trust

If this is provided for in the charter and is consistent with the general goals, the cooperative may have other activities that will be financed from the mutual fund. However, the amount of funds allocated for this purpose, by law, should not exceed 50% of the total amount raised from the shareholders of the consumer credit cooperative, otherwise this will already be the main activity.

Reserve fund of a credit consumer cooperative

Already from the name it is clear that the funds that are put into this fund are intended “just in case of fire” and are designed to cover expenses and damage in the event of unforeseen circumstances. The legislation clearly states the need to form this fund, therefore, when checking, regulatory authorities always pay attention to the accuracy of compliance with reserve standards.

Requirements for a credit cooperative

All requirements for a PDA can be divided into two groups:

• Registration – relate to preparation for the work of the organization, and have already been considered.
• Functional - relate directly to activities, they affect such important issues as the amount of reserves or the upper limit on loans issued (most of these financial standards are defined in Article 6 of the Law “On Credit Cooperation”). For organizations with a period of activity of less than two years, a number of benefits are legally provided.

Maximum loan amount

Each shareholder of a credit cooperative can count on receiving finance no more than 10% of the total loan debt of the credit cooperative (for young organizations this figure is twice as high). This amount is derived from the financial statements at the end of the previous reporting period, allowing the funds collected to be distributed more equitably among a larger number of participants.

The amount of the reserve fund

Legislatively defined reserve standards are at least 5% of the amount raised from shareholders, and it must be separated from the mutual financial assistance fund (for example, in a bank account). For credit consumer cooperatives with a period of operation of up to two years, the minimum is 2%, but the presence of such a fund is strictly mandatory for them.

Rates on accepted deposits

Credit cooperatives are attractive for placing depositors' funds due to high interest rates, which significantly exceed bank rates, but the risk of non-return of funds invested in CPCs is also higher. The legislation defines the maximum interest on deposits as the refinancing rate multiplied by a factor of 2.5 (for June 2019 this will be 22.5%).

Activities of credit unions

According to the Bank of Russia, as of January 2019, 3,058 credit cooperatives operate in our country, more than half (52%) are not members of self-regulatory organizations, and 3% of organizations have over 5,000 shareholders. According to statistics, about 1.2 million Russians are shareholders, and the average amount of assets per member of the CCP is almost 30,000 rubles. Analyzing these figures, we can come to the conclusion that a large segment of Russians continue to trust their finances to CCPs, and if the numbers do not decrease every year, it means that shareholders are satisfied with the proposed conditions.

Consumer cooperative - pros and cons

If we consider the CCP from the point of view of the profitability of the financial participation of an individual depositor, then, like any other financial organization, it will have its advantages and disadvantages. One of the main positive qualities of a PDA can be called a conceptually thought-out emotional presentation of a commercial proposal. The future shareholder receives an invitation not to a “commercial organization” where “the main goal is making a profit”, but to a “mutual assistance fund” where people want to help each other. It sounds attractive, what they say is soulful. Other benefits include:

• high return on deposits;
• ease of obtaining loans;
• participation in management and decision making;
• high level of protection against risks when insured by SRO.

But there are also disadvantages:

• compensation to the shareholder can be only 5%;
• young credit institutions often have low fund levels;
• insurance in an SRO leads to unnecessary expenses, which are reflected in the loan rate.

How to distinguish a PDA from a financial pyramid

Some similarity in working methods makes it possible to disguise a fraudulent financial pyramid scheme as a respectable PDA. Instead of placing the money received in the form of loans, such a pyramid pays dividends from it to previous investors, all the time attracting new members. Quite predictably, such activity cannot last long, so age over 2-3 years will be a good guarantee.

Other differences between a serious PDA include:

• Belonging to the regional union of credit cooperatives.
• The organization's management system involves an elected board and annual meetings of shareholders.
• Advertising appeals to reliability or simplicity; there are no promises of bonuses for referring someone else.
• A reliably operating CPC always issues loans to its shareholders.

Video

Introduction

Over the past 9 years (since 1993), a new participant has appeared in the world of personal computers - the personal pocket computer (PDA). Devices based on the Palm platform, which appeared in 1996, played a major role in the spread of this type of technology.

The purpose of this work is to consider the most popular platform (operating system along with the device) PalmOS PDA.

The work is divided into 3 parts - History, Working in PalmOS, Programming in PalmOS, and at the end of the work, an example shows how to create a simple application for PalmOS.

Here we consider versions of PalmOS - 3.0 and higher, and the latest models of handheld computers, because Nowadays, the first models of such devices with OS versions up to 3.0 are rarely seen, and they should not be considered because they are missing many elements. (for example, data exchange between PDAs and Internet support)

The figure shows a hand-held computer connected to a desktop PC using a set-top box (cradle).

PDA - Pocket Personal Computer

A PDA is an ordinary computer with only limited resources - power, memory, processor, screen, input / output means. But the main requirements for such devices are long-term operation without recharging the batteries, size, weight, convenience, reliability and quick feedback to user actions. It is also assumed that for normal operation of this device you must have a regular desktop computer (with the Windows, MacOS, Unix operating system)

The very first name of such devices is PDA (personal digital assistant), you can also find the name “handheld PC”, “handheld”. A PDA is usually understood as a device that fits in a pocket and can operate for a long time on batteries; this device must also have at least the functions of an organizer.

Organizer - from the word “organize” - to organize, plan, arrange, form, put in order, (translated from English) An organizer is a device that looks like a calculator, into which you can enter phone numbers and addresses (there is a keyboard), it has clock and alarm clock. In Soviet countries, such devices were called Electronic Notebooks (see history of PDAs).

There are several types of PDA devices, one of them is pocket computers. PDAs are divided into:

Palm - or simply “Palms” (emphasis on the “a”), the very first of all listed.

• 1. PPC - (Palm-size PC), this is all that runs under WindowsCE 2.0-2.1, they look like Palm.
• 2. HPC - (Handheld PC) PDA with a small keyboard, available with WindowsCE, EPOC32.
• 3. Pocket PC - (the most modern) multimedia PDA with WindowsCE 3.0, they differ from PPC in increased resources (memory, processor)

Palm are the most popular and widespread PDAs; they appeared in 1996 and their main purpose is as an Organizer attached to a desktop PC. Further in the text I will simply call them “palm”, by analogy with the word “laptop”. (Palm - palm, translation from English)

The history of Palms dates back to 1992, when Jeff Hawkins founded Palm Computing. In 1996, the Palm Pilot portable electronic notebook was released, “understanding” handwritten letters written on it with a special pen - a stylus. In September 1994, Palm Computing was acquired by U.S. Corporation. Robotics, which in turn turned out to be eaten by 3Сom. By 1998, 1 million devices were sold worldwide.

Palm trees are the best organizers. In addition, with Palm you can access the Internet, send mail, Palm can be used as a dictionary and reference book, you can listen to music, read books, store arrays of data in it, use it as a voice recorder, and play games.

Some opportunities are potential - e.g. They are not on the PDA when you purchase it, but they may appear if you also buy an additional device. For example, surfing the Internet or listening to music is not possible on all PDAs (see additional devices for PDAs)

Despite the fact that they do not have a keyboard, entering information into them is very simple - the user simply writes in it like in a notepad with a small pen (stylus)

All models have a backlit touch screen (responses to touch), an infrared port for exchanging data with other Palms. Some Palms are equipped with slots for additional devices - modem, radio, camera, MP3 player, pager. All Palms can work on average for a week without recharging their batteries. There are a huge number of paid and free programs for them.

An infrared port is a directional emitter of infrared light. Widely used in remote controls. Recently, such transmitters are used for wireless communication of various devices, mobile phones and PDAs.

The owner of the Palm must periodically connect the Palm to the desktop PC in order to synchronize; this is necessary for, firstly: placing new information and programs on the PDA, and secondly: making a backup copy of all information in the PDA.

The PDA can remain without batteries for about 10 minutes, otherwise all information is lost; in this case, a backup copy will help restore everything.

The listed capabilities and characteristics are present in all today's PDAs, and are the standard today.

PPC running WindowsCE OS appeared after Palm. They have a more powerful processor, more memory, and a larger and better screen. They can also be used as an Organizer; they have the necessary programs. The WindowsCE operating system (CE - compact edition) is a stripped-down copy of Windows95. For the user, this means that WindowsCE has everything - smaller versions of Word, Excel, Internet Explorer, you can work with files and folders, there is an explorer, an analogue of the control panel, a help system, etc., modern models have more powerful multimedia support - music, animation, video. There is only no desktop. Despite their power, they work slower than Palms.

PocketPC are the next generation PPC based on WinCE, all of the above applies to them, the whole difference is that there are more resources (memory 32-64MB, processor 160-210MHz), and they have WinCE 3.0 installed (+ new technology for connecting external devices - jackets). Therefore, it is more convenient to do some things in it: for example, thanks to a high-quality screen, it is more convenient to use the Internet, read books, format text, work with tables, look at pictures, you can listen to high-quality music on them, or record speech on a voice recorder. There are negative aspects - and the battery life has dropped catastrophically - the batteries need to be charged every day.

In WinCE you can also enter text by handwriting, but another technology is used which is worse than in Palms (the percentage of errors when entering a test is higher), in PocketPC this system has been improved (in addition, an analogue of graffiti has appeared)

These models also connect to a desktop computer for synchronization.

It should be noted that models based on WinCE are absolutely not compatible with Palms; moreover, this data cannot be transferred from a WinCe PDA to Palms via the infrared port.

HPC- these are PDAs that have a small keyboard, their screen is wide, they look like smaller laptops. They have the WindowsCE Pro (special version) or EPOC (EPOC32) operating system installed, and there are also PDAs with other operating systems. These models were created to eliminate the disadvantage of keyboardless PDAs - the lack of a keyboard, and a wide screen provides additional advantages. Along with the organizer functions, they also contain Word, Excel, Internet Explorer.

WindowsCE Pro is even more similar to Windows95, there is a desktop, a full-fledged control panel, and you can print from them to a printer.

They connect to a PDA, all WinCE models have a PC card and a Compact Flash slot (for connecting additional memory, modems, etc.), you can connect headphones.

Model table