The rapid development of modern communication technologies has led to the adoption of wireless communication methods for data transmission in many applications. The circuit composed of codec chips PT2262 and PT2272 is widely used in various wireless remote controllers, wireless alarms, toys and other small electrical devices because of its small size, low power consumption, strong function and low cost. However, such a circuit is rarely used in the communication of multiple bytes of data, and has certain limitations. This paper mainly introduces the use of 433 MHz high-frequency transmitting module and receiving module to make SMS communication in multi-machine wireless ASCII format. The communication method is based on the 433MHz high-frequency transmitting module and the receiving module, and defines a wireless transmission protocol to realize multi-byte data communication between any two machines. Host circuit design Since the amount of programs involved in the system is relatively large, the storage capacity of the Flash program memory is not required to be too small; for the transmission and reception of the short message, the EEPROM data memory module is used, and the content stored in the EEPROM data memory is not lost when the content is lost. Receive and decode require pulse width capture and compare functions, capture/compare/pulse width modulation CCP module is used; separate timers are used for transmit, receive, and clock. The number of timers required is not less than 3 Based on the design requirements, Microchip's PICl6F877A chip is used as the main controller of the system. The circuit is mainly composed of a main control chip, a crystal oscillation circuit and an online simulation interface, as shown in FIG. 2 . The MCLR, RB6, and RB7 interfaces are used in the design as an in-circuit emulation interface. Transmitting and receiving circuit design A 433 MHz high frequency transmit and receive module is used. The 433 MHz high-frequency transmit circuit starts up and emits a constant-amplitude high-frequency signal when the control pin is high. It stops oscillation when the control pin is low. Therefore, it is possible to perform amplitude keying (ASK modulation) on the high frequency circuit with the control pin, which is equivalent to an amplitude modulation with a modulation degree of 100%. When the receiving module receives a constant-amplitude high-frequency signal of 433 MHz, the signal pin outputs a high level, otherwise it outputs a low level. Therefore, the high and low level changes of the receiving signal pin correspond to the high and low level changes of the transmitting control pin. Multiple receiving modules can simultaneously receive signals transmitted by the same transmitting module, which can be transmitted by one machine and received by multiple machines at the same time. The circuit shown in Figure 3 is a transmit and receive module for a high frequency 433 MHz carrier. The high-frequency transmitting circuit of 433 MHz is high-level when the control pin B5 is high, the three-stage tube T1 is turned on, the T2 emitter level grounding starts and emits a signal of equal amplitude high frequency 433 MHz; when the control pin B5 is low level, it stops. oscillation. Therefore, amplitude keying (ASK modulation) can be performed on the high frequency circuit by the control pin B5, which corresponds to an amplitude modulation with a modulation degree of 100%. When the receiving module receives the equal-amplitude high-frequency signal of 433 MHz, the signal pin outputs a high level to the C2 port, and outputs a low level if the equal-amplitude high-frequency signal of 433 MHz is not received. Therefore, the high and low level changes of the receiving signal pin correspond to the high and low level changes of the transmitting control pin. For example, if the waveform shown in Figure 4 is input to the B5 pin, the same waveform will appear on the C2 pin of the receiving module. Note that the control signals of B5 and C2 are issued by RB5 and RC2 of the master chip PICl6F877A, respectively. Design of liquid crystal peripheral control circuit Adopt Nokia 3310 LCD display module. The LCD is 84 & TImes; 48 dot matrix LCD screen, one screen can display 4 & TImes; 7 (12 & TImes; 12 dot matrix) Chinese characters, or 6 & TImes; 14 (6 × 8 dot matrix) English, numbers, punctuation and other characters. The liquid crystal display is light and short, low power consumption, and is often used for mobile phone display. The liquid crystal peripheral circuit is shown in Figure 5. In this design, the Nokia 33lO LCD is powered by a 3 V voltage. Among them, 1 pin is the power pin, 6 pin ground wire, 2 pin is SCLK, 3 pin is SDIN. The 4 pin is the data/address selection end, which respectively gives 4 pins high and low level, which can control the MCU to write data or write commands to the Nokia 3310 LCD. The 5 pin is the enable terminal and is active low. The 8 pin is the reset terminal and is active low. The 11-pin is connected to the positive stage of the backlight power supply, and the 12-pin is connected to the control stage of the backlight power supply. 9, 10 pin is the speaker of the Nokia 3310 LCD. The sound effect of this speaker controlled by a single-chip microcomputer is not ideal, so use the DC self-contained oscillation buzzer. To prevent the buzzer and backlight from affecting the LCD power supply, the buzzer and backlight are powered by a 5 V power supply, separate from the LCD power supply. The design method described in this paper integrates coding and decoding technology, communication protocol technology, anti-jamming technology, editing short message technology, and liquid crystal dot matrix display technology. It can realize SMS messages of 70 ASCII characters between any two machines. It can edit SMS messages like ordinary mobile phones. The machine can be named by the user to distinguish other machines, realize one-to-one communication, and can also use universal name ( "WDX") enables one-to-many communication. You can store a text message that you send out, or you can store a text message you just received and an old text message. The human-machine interaction interface of the whole system is friendly, similar to the ordinary mobile phone system, with operational prompts and easy operation. The layered protocol in this design makes it easy to replace wireless communication modules with other wireless modules with better performance.
OEM & ODM Disposable Vape
WEIKA Technology has been specializing in the new technology R&D and design of the electronic atomizer products. It provides one-stop high-quality services with products R&D, packing design, mass production and brand marketing. It is a well-known OEM processing base at domestic and abroad and a dream workshop for famous brands!
WEIKA was established on the customer's pursuit of quality, the unique choice of packaging design and the guarantee of product delivery.
WEIKA starts from the strict control of raw materials and insists on the selection of food grade raw materials. All products of WEIKA have passed the Safety food certification of China, the European Union and the Food safety FDA of the United States.
In the production of products, WEIKA introduces the automatic production equipments, from production to packaging, the whole system of tracking, efficient and orderly process, achieving daily efficient output. WEIKA pays attention to the details of each process control. The first class dust-free production workshop has passed the GMP food and drug production standard certification, ensuring quality and safety.
We choose the products with a traceability system, which can not only effectively track and trace all kinds of data, but also ensure good product quality.
WEIKA team creates the best quality with extreme ingenuity.
We supply OEM rechargeable disposable vape pen,OEM disposable electronic cigarette,ODM disposable vape pen,ODM disposable electronic cigarette,OEM/ODM vape pen e-cigarette,OEM/ODM atomizer device.
OEM disposable vape pen,OEM disposable electronic cigarette,ODM disposable vape pen,ODM disposable electronic cigarette,OEM/ODM vape pen e-cigarette Shenzhen WeiKa Technology Co.,Ltd. , https://www.sze-cigarette.com
