ZigBee is a low-cost, low-power wireless network technology based on the IEEE 802.15.4 standard. Through the ZigBee protocol stack, each ZigBee node can form a ZigBee network with large node capacity and wide communication range. H.264 is the best video compression standard today, with the advantages of low code rate, high image quality and strong fault tolerance. Using a ZigBee network to transmit H.264 video streams is a good solution for implementing a wireless video transmission system. Through the specific development examples, the design and implementation of the scheme are discussed from two aspects of hardware and software. 0 Preface ZigBee is a wireless network technology based on the IEEE 802.15.4 standard with low cost, low power consumption, large network capacity and wide communication range. It can support up to 65,000 nodes. ZigBee has three operating bands, 868 MHz, 915 MHz, and 2.4 GHz. When operating at 2.4 GHz, it has the highest transfer rate of 250 KB/s. Obtaining good image quality and low-bandwidth image fast transmission with as little storage as possible has become two major challenges in video compression. To this end, the ISO/IEC and ITU-T international standardization organizations have jointly developed a new generation video compression standard H.264 [3]. H264 has the advantages of good image quality, strong continuity, high dynamic image quality, high compression ratio and adjustable code stream rate. This paper discusses the use of H.264 hardware codec, ARM9 CPU core i.MX27 and microprocessor Z24 with ZigBee protocol stack to form a wireless video transmission system. The overall design of the system is shown in Figure 1. The entire ZigBee network consists of a ZigBee coordinator, multiple ZigBee routers, and ZigBee wireless video terminals [4]. Because the CC2430 integrates a 2.4 GHz DSSS RF transceiver and microcontroller controller, ZigBee devices can be implemented using the CC2430 single chip. The ZigBee Coordinator is used to form the original ZigBee network and allocate 16-bit network short addresses for each ZigBee router and ZigBee wireless video terminal joining the network. The ZigBee router plays the role of routing and relaying in the ZigBee network, transmitting data for each ZigBee wireless video terminal and expanding the range of wireless data transmission. The ZigBee wireless video terminal can perform two-way wireless data communication with each other according to the allocated 16-bit network short address [5]. The i.MX27 adopts the Linux operating system. Under Linux, the captured image is hardware-compressed and encoded, and the data between the ZigBee wireless video terminals is wirelessly transmitted in the form of H.264 code stream. Considering that H.264 software codec needs to consume a lot of CPU resources, the Freescale microprocessor i.MX27 with H.264 hardware codec and ARM9 CPU core is selected in this scheme. On the one hand, the ARM9 CPU core is responsible for sending the YUV image data collected by the camera to the H.264 hardware encoder, and transmitting the H.264 code stream output by the hardware encoder through the ZigBee microprocessor CC2430. On the other hand, the H.264 code stream is received by the CC2430 and sent to the H.264 hardware decoder, and then the YUV image data output by the hardware decoder is displayed on the liquid crystal screen. The ZigBee microprocessor CC2430 is responsible for the transmission and reception of the H.264 code stream and communicates with the i.MX27 via the SPI interface. The hardware composition of the ZigBee wireless video terminal is shown in Figure 2. In order to achieve image acquisition, this solution uses a CMOS camera with OV9650 chip, and the acquired image is transmitted to the H.264 hardware encoder through the CSI interface of i.MX27. For the display of images, select Innolux AT070TN83-V.1 (16:9, 800 & TImes; 480) 7-inch TFT LCD screen. The screen supports an 18-bit digital RGB interface in the format of RGB666, which means that each pixel consists of 6 bit red, 6 bit green, and 6 bit blue to form 18 bit data. This screen is connected to the i.MX27's LCDC controller mainly through 18 data lines (LD[17:0]), frame sync (VSYNC), line sync (HSYSNC), and clock (LSCLK). A Samsung K9F2G08R0A NAND Flash chip (256 M&TImes; 8 bit) is used to store the system's Bootloader (RedBoot), Linux kernel, file system and video programs. Two pieces of Infineon Technologies' HYB18M512160AF-7.5 chip (4 Bank&TImes; 8 M&TImes; 16 bit) form a 128 MB DDR, which is mainly used to load the Linux operating system and run video codec. Design a 10-pin JTAG interface for programming the system's bootloader, Linux kernel, and file system. The MAX3232 is used to form a UART interface for returning debug information to the MiniCom for display. Since the processor core requires 1.8 V and 1.5 V, and the memory and external I/O require 3.3 V, the input voltage of the entire system is set to 5 V, which can be completed to 3.3 V and 1.8 V through the DC-DC converter. , 1.5 V voltage conversion. With a 26 MHz active crystal, the crystal is multiplied by up to 400 MHz with a PLL circuit on the i.MX27 chip. The ZigBee communication module is based on CHIPCON's CC2430 microprocessor. The SPI interface of the CC2430 is connected to the SPI interface of the i.MX27, and the H.264 code stream is transmitted through the SPI interface. The hand-held Electric Fan is intelligently controlled and adjusted in three gears, and the wind power can be adjusted according to your own needs. The lithium battery of the Rechargeable Fan has strong versatility, recyclable charging, low use cost, simple and elegant appearance, firm structure, small size, light weight and convenience. 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