What Is a PDA Cell Phone?

PDA stands for Personal Digital Assistant. As the name suggests, it is a digital tool to assist individuals in their work. Mainly provide functions such as memo, address book, business card exchange and schedule. Of course, with the advancement of technology, some new functions such as digital recording have been added. Now the definition of PDA is actually very vague. All products have adopted this collective name, and many people even refer to PDAs as handheld computers.

Chinese name: PDA
Meaning: Personal digital assistant

Use: Digital tools to assist personal work
Classification: Electronic dictionary, handheld computer, etc.

1 pda mobile phone Overview

In recent years, ordinary personal digital assistant (PDA) products have mainly focused on personal information management (PIM) functions, such as storing phones, searching phones, and memo pads. With the rapid development of wireless Internet, a large number of products with functions such as sending and receiving email (E-mail), wireless Internet access, etc. have appeared. As a kind of information terminal equipment, mobile phone is undoubtedly the most convenient tool for mobile wireless access, but it does not have advantages in screen display, data processing, mobile computing, and memory capacity. The combination of the two has even become a PDA. Breaking through the direction, PDA mobile phones will become the ultimate trend.

At present, major domestic and foreign mobile phone manufacturers have successively launched PDA mobile phones, and they are almost all products with multimedia functions, wireless Internet access, and mobile phone functions. The advantage of a PDA phone is that the advantages of both parties are concentrated, so its popularity may be the same as that of current handheld computers.

2 pda mobile phone 2. Main Specifications

The technical indicators of PDA phones are the same as those of GSM phones.

3 pda mobile phone 3. Basic functional characteristics

PDA mobile phones have the functions of mobile phones and PDAs, which can record calendar diaries, address books, support GPRS, send and receive E-mail, browse web pages, online games, send and receive short messages, and instantly download wonderful application software.

Main menu: a. Icon, click each icon to directly enter the menu of this column; b. Start, including document, settings, task management, alarm management, shutdown system; c. Box, return directly to the main menu; d. Keyboard , Zoom input keyboard; e. Battery, remind battery level. f. Time, you can enter the clock menu to change the time, alarm and sound settings; g. Call, implement the function of making a call.

System settings: You can change the sound and brightness settings, password settings, timing settings, handwriting settings, and phone settings.

Business card book: record personnel address and contact details in detail.

Notepad: Record the current affairs.

Schedule: Check the perpetual calendar and set the appointment schedule.

Memo: design graphic scheme.

Personal financial books.

Touch screen and handwriting input.

GPRS and E-mail.

Short message: there are functions such as handwriting input with short message, group sending, short message preset, short message receiving.

Support fax and WAP.

English-Chinese / Chinese-English Dictionary: Dynamically downloadable.

Program download: Chinese e-books, games, securities software, real-time stock information, weather forecast, etc. can be downloaded.

Online games: downloadable dynamically.

MP3 and physical video.

PC communication.

4 pda phone 4. Basic working principle

The working principle of a PDA mobile phone is shown in Figure 1. In brief, it consists of two parts: PDA and GSM mobile phone, including microprocessor, main memory, touch display, keyboard, GSM module, human-machine interface, and system software .

4.1 PDA pda phone 4.1 PDA part

The PDA consists of a microprocessor, memory, a touch-sensitive display, a keyboard, and system software. The working process of the PDA is that the microprocessor obtains the user's instructions through the input device, and the system software performs the judgment, calculation, and comprehensive processing, and displays the results required by the user in the output device.

Microprocessor U1: It is the core of the PDA. All the work of the PDA is controlled by U1.

Input devices: Includes keyboard and touch display.

Output device: touch display. The grayscale of the PDA's black and white display can be adjusted through software. At present, the use of color display on mid-to-high-end PDA phones is a trend that facilitates browsing of web pages and pictures. The latest TFT color screen has a faster refresh speed and a thinner thickness , More convenient to browse pictures. The memory F1 is a medium where the program runs and stores data.

Operating system: Generally, the operating system developed by the manufacturer or Palm, Microsoft's Windows CE, and the EPOC operating system supported by mobile communication manufacturers such as Motorola, Nokia, and Ericsson.

As for the operating systems independently developed by various manufacturers, due to their closed nature, they cannot choose to install a variety of software to expand their functions like operating systems such as Palm or CE. The scalability is limited in many ways.

Palm OS is a 32-bit embedded operating system, built on the core of AMX real-time multitasking, and can handle complex workflows. Palm combined with the synchronization software HotSync can synchronize the information on the PDA phone with the PC, extending the functionality of the desktop computer to the PDA phone. Motorola A6288 uses Palm operating system.

EPOC is an operating system launched by Psion Software. The early release of EPOC16 is a 16-bit operating system. The new version of EPOC32 is a 32-bit multitasking operating system. In the PDA mobile phone market, EPOC is a powerful rival of Palm and Windows CE, and Nokia 9210 uses EPOC operating system.

Windows CE is a masterpiece of Microsoft's involvement in mobile digital products. It has strong advantages for multimedia applications, and its potential for upgrading and expansion is considerable. Its application in PDA phones is the PocketPC operating system, which is used by Siemens' Multimobile and Mitsubishi's TRIUM MONDO.

4.2 pda mobile phone 4.2 mobile phone part

The design of the mobile phone part of the PDA mobile phone is the same as that of the general GSM mobile phone, except that the display part is replaced by the PDA touch screen, and the man-machine interface adopts the PDA operation interface.

4.3 PDA PDA phone 4.3 PDA phone working principle

It can be seen from Figure 1 that the PDA mobile phone manages the entire mobile phone work through the PDA microprocessor U1. The functions of the PDA part are controlled by the PDA operating system U1, and the functions of the mobile phone are mainly controlled by the system software in the mobile phone module.

The PDA system software and mobile phone control software are placed in the main memories U3 and U4, and the mobile phone system software is placed in the internal memory of the GSM module. When a user uses a PDA phone, the desired menu is selected through operations on the touch screen. When the user selects the PDA function, U1 calls the control program in U3 and U4 to implement the PDA function; when the user selects the function related to the mobile phone, the microprocessor U1 uses the control program in external memory U3 and U4 The serial port uses AT commands to control the CPU U2 of the mobile phone module, and then completes all the functions of the ordinary mobile phone through the mobile phone system software.

At present, most domestic manufacturers use a GSM module in the design of PDA mobile phones, plus antennas and human-machine interfaces to complete the design of a mobile phone. The GSM module includes radio frequency, baseband, GSM protocol stack, and application software. The advantage of doing so is The design and debugging are simple, easy to produce, and the function upgrade is convenient and fast. The disadvantage is that the cost is slightly higher.