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Abstract: Introduces one kind briefly by the public switched telephone network date transmission medium residential district automatic peaceful against alarm system. The system by the micro controller core, in the Japan plot the inhabitant provides the safe surveillance and the service, has the reliability to be high, the cost low, easy to popularize and so on merits.

    Key word: Intelligent plot telephone call DTMF receiving and dispatching liquid crystal display

Along with the people living standard’s unceasing enhancement, the family safe service is bringing to people’s attention gradually. Establishes the networking alarm system in the residential district, enables the plot administrative center to carry on the stitch in time to inhabitant’s police sentiment, is precisely the people hoped. Telephone equipment’s large-scale popularization, causes the use public telephone network to realize the plot auto-alarm joint logistics system possibly to become.

First, system principle of work and hardware design

The system take micro controller AT89C52 as a core, is composed of two parts: A part is establishes in the resident housing front end the warning; Another part is establishes in the estate management center surveillance terminal. The former, by imposition in housing each kind of sensor collection corresponding simulation quantity signal, when the signal achieves the warning threshold time, the start alarm device, the alarm message will pass to the residential district through the telephone channel the estate management center (or corresponding safe Service sector). The latter, will receive the alarm message carries on the memory and the demonstration, simultaneously by the sound, the light form notice administrative personnels takes the corresponding measures to process to the police sentiment.

    The sensor part including the gas leakage examination module, the gate magnetic switch module, the infrared human body moves the survey module, the temperature/smog sensing module as well as the glass stave vibration module and so on. The sensor array’s modular design enables the user to simulate needs to fluctuate the function, strengthened system’s compatibility.

Considered the home use alarm system communication the data quantity is not big, may use the double sound multi-frequency long range data transmission technology (DTMF) to transmit the warning data. By sensor array or by-hand input way collection alarm message, through public network long-distance connection estate management center surveillance terminal, when the front-end system confirmed that needs to report to the police when and to help, automatically dials the monitor terminal. The connection later (will plant and so on by the DTMF way transmission alarm message including this aircraft number and police). After monitoring the terminal receives the line signal, controls the DTMF transmission, the receive chip simulation to pick machine the movement, receives the police sentiment information, the start acousto-optics warning, obtains the warning place according to this aircraft number information, will plant and so on information the current time as well as the warning place and the police to store in the Flash memory to prepare will inquire in the future, simultaneously will demonstrate these information on the liquid-crystal display. The administrative personnels press down eliminate the key to eliminate the acousto-optic warning, and takes the countermeasure according to the situation, the process time simultaneously is also recorded in system’s memory. Overall system’s work flow and monitor terminal’s functional block diagram like chart distinction like chart 1, shown in Figure 2.

    The system use dodges the fast memory preservation alarm message, with the aim of inquiring in the future. Moreover, the plot inhabitant’s telephone number and the inhabitant address correspondence table also has in which, uses in alarm message’s telephone number information which will receive transforming into the inhabitant address message.The system selects 28SF040 4MB SuperFlash EEPROM. This memory causes its read-write speed through the optimized connection characteristic to be quick, the power loss to be very low. In addition, this chip has also used the hardware and the software protection method carries on the effective protection to the internal memory data. In the hardware aspect, pulls pin OE low either sets pin CE or WE high as well as, when power source loss of voltage to 2.5V below, can forbid toward the internal write data, when this component electricity will be at the software protection condition automatically. When is in the software writes the protection condition, must to 7 specific address units carry on reads the operation to be able to solve the protection. Similarly, carries on after other 7 specific address unit reads the operation causes the component to be at writes the protection condition, this kind of design has guaranteed the stored datum reliability.

The time is in the alarm message the indispensable constituent. This system uses RICOH Corporation’s RS5C348 clock chip to supply the time information. This chip carries on the connection by the SPI main line way and CPU, has the leap year automatic judgment and the voltage measuring ability, obtains the accurate time and the calendar information only need read several registers, simplified the circuit design, enhanced the design reliability. But because AT89C52 does not have the SPI connection, therefore when programming must use the software to simulate the SPI connection succession.

    After receiving the alarm message, must prompt information and so on time, place, alarm, so that the administrative personnels can make the response and the processing emergencies promptly. What the system uses is EPSON Corporation’s graph lattice type liquid crystal display driver SED1353 actuates SHARP and 320×240 lattice LM32019T LCD. This driver may with Intel 51 series or the Motorola 68 series MCU direct connection, supports 1024×1024 lattice LCD, has the minute screen demonstration function, may 2 completely different dot pattern demonstration on the high and low 2-and-a-half screens. Established the SRAM connection as the optimized demonstration speed and the performance to take the demonstration buffer, the buffer capacity may reach 128KB. SED1353 and 89C52 connection hint as shown in Figure 3, MEMCS, MEMR and MEMW aim at the signal connection which demonstration buffer SRAM selects patches or strips of land as worth saving for seed, reads and writes.

Before order to avoid having the warning, to the telephone equipment and the line destruction, the system selects the joint logistics method, the alarm message may through other inhabitant’s telephone alignment monitor terminal transmitter data.

Second, system software design

Supervisory system’s major function is the alarm message which will receive while acousto-optic warning’s carries on the demonstration and the memory, the store content may read in the computer through the RS232 connection in order to inquire, as well as using calculates the mechanical school positive system the clock. The master routine completes the function is MCU is one by one related SFR the initialization, the user definition memory cell initialization, as well as each main periphery component (for example clock chip, telephone chip, LCD actuation chip) and dodges the fast memory and so on initialization. The telephone interface circuit’s line signal receives monolithic integrated circuit’s outside fracture on-line, the interrupt servicing subroutine’s function is receives the alarm message and saves and the demonstration, main software flow as shown in Figure 4. The system establishment’s 2 pressed keys correspond the elimination acousto-optics warning (i.e. administrative personnels to make response separately to warning) and the application and the superior microcomputer carry on the correspondence (including to read memory content in microcomputer, and will preserve reads in microcomputer’s address telephone correspondence table dodges in fast memory the function using microcomputer leveling system’s clock chip’s time establishment), main software flow as shown in Figure 5.

What in dodges in fast memory 28SF040 to deposit receives the address telephone correspondence table which the alarm message and decides in advance into. Alarm message including warning time (year, month, Japan, divides, second), the warning place (, unit, floor, room), the police plants and administrative personnels’ process time (, divides, second). According to BCD code depositing, every 1 0.1 bytes (in which “year” takes latter 2 digit), gathers takes in logical 1 catalog, the concurrent 14 bytes, considered the programming is convenient, take every 16 bytes as 1 record. Moreover, the address telephone correspondence table supposes for every 8 bytes is 1 record, in each record the telephone number and the address by BCD code depositing, respectively occupy 4 bytes. If has the 16KB depositing address telephone correspondence table, altogether may record 2048 inhabitant’s address telephone information and 31743 danger signal records, saves the 1st record uses for the address which deposits in the memory the final 1 danger signal record 1st byte institute to be, is advantageous for stores when the new record the localization.

Table 1 controls the register

The system selects 320×240 lattice LCD, the standard Chinese character for 16×16 the lattice, the character for 8×16 the lattice, namely on LCD may demonstrate 15 lines of 20 row Chinese characters. The liquid crystal display control and the driver built-in 14 control register, control display’s active status, like Table 1 arranges in order. When IOCS is the low level, its address controls by AB0~AB3. And R1 is the pattern register, everybody’s function is as follows.

(1) DISP:DISP=0, closes the demonstration; DISP=1, opens the demonstration.

(2) REV:REV=0, obviously; REV=1, highlighted.

(3) PANEL:PANEL=0, actuation list LCD screen; PANEL=1, actuates the double LCD screen.

(4) OR:OR=0, demonstrated that divides into the high and low two screens, the connection demonstrated; OR=1, demonstrated that around divides into two, the superimposition demonstrated.

(5) GRAY:GRAY=0, black and white demonstration; GRAY=1, gradation demonstration.

(6) 4/8 choice actuates when LCD data width.

4/8=0,4 bit data transmission; 4/8=1,8 bit data transmission. Has nothing to do with the data bus, suggests the establishment width, this option supposes is 0.

(7) LCDE:LCDE=0, LCD power source pass; The LCD=1, LCD power source starts.

(8) RAMS: Demonstrates the memory (VRAM) the address wire disposition. RAMS=0, address 8K×8 SRAM’S; RAMS=1, address 32K×8 SRAM’S. The suggestion establishment is 1.

    For example, the establishment liquid crystal box for the single module, is divided the screen, the black and white pattern, the screen 1 defines as the upper half, the screen 2 defines as the lower part, and screen resolution for 320×240. Demonstrated that the memory and the monolithic integrated circuit memory unification address, demonstrated the memory operates by the monolithic integrated circuit direct addressing. When screen initialization, various registers’ establishment parameter is as follows:

R1=83H, R2=27H, R3=7EH, R4=EFH, R5=0, R6=R7=0, R8=C0H, R9=12, R10=77H, R11=0, R13=R14=R15=0.

Character display regarding actual situation’s in that usually may draw the character on the coordinate paper the shape. Each byte’s content which takes according to it manufactures a value table (saying that lattice data), places this table in ROM, when demonstrates the character, the calling program reads in this table VRAM in the relevant position to realize the demonstration. In the ROM this value table is called the matrix. If the character are very few, like this manufactures still permissible. If must demonstrate that completely the ASCII code or the demonstration Chinese character, must try to apply mechanically the ready-made matrix. The ASCII character may select UCDOS the ASC16 document to make the matrix storehouse, the Chinese character character may select UCDOS the HZK16 document to make the matrix storehouse. In addition, will also have some based on UCDOS either the Windows matrix extraction software, after the input character or the Chinese character, will obtain the corresponding matrix, this regarding the number not big character which or the Chinese character must demonstrate is very convenient. Because this system only plants the part in the police to involve some Chinese characters, has is some digit again, therefore uses is this simple extraction matrix method.

Concluding remark

This article will state the system already and puts the operation through the comprehensive test, the residential district peaceful against alarm system improves unceasingly will certainly enhances the positive influence unceasingly to the intelligent building system’s construction and the development and the living standards.