A. UNV-SIM868 Development Board The UNV-SIM868 development board is a mobile module launched by SIMCOM Company with superior performance and compact design. Onboard MICRO SIM card, reserved headphone microphone welding port. The antenna interface is an IPEX-MINI interface, which is small and easy to use to connect various antennas. The onboard high-efficiency DC-DC power module supports 5V-18V wide voltage power supply and can be reserved for power supply, which facilitates power supply control and reduces the power consumption of the development board. The main control serial port has level matching function and supports 3.3V to 5V microcontroller or other control systems. GPS+GSM GPRS Beidou function. 2. Data supported by the module 1: Supports GPS, BD, GLO, LBS base station positioning, omnidirectional positioning 2: RTC battery backup, supports hot start hot start, positioning speed is greatly enhanced 3: GPS positioning data supports independent collection and serial port configuration, More choices, more convenience. 4: Positioning data also supports GSM serial port and can be configured through AT commands, which is faster and more convenient. 5: Computer debugging videos are coming, allowing you to master 868 functions faster 6: Newly added various microcontroller programs, which greatly facilitates the rapid development of microcontrollers 3. Module 1. Rich interfaces, unified planning of commonly used interfaces, integrated headphone jack, The lead storage space is large, and there are 2 rows of pins, which can be used as power control pins, can control the power switch, and can achieve remote unmanned control. 3. The main serial port and GPS serial port integrate level matching circuits, and the compatibility is very stable. 4. 2 status indicators, the module status is clear at a glance, simple and fast. 5. 50R antenna impedance matching, the GSM signal is so strong and crazy in the environment that 31 is full. 6. Exclusive firmware supports base station positioning, and can be positioned normally even when the GPS signal is not good. 7. The same quality, the same chip, four Among the modules 1. RTC standby power supply: supplies power to the RTC after the device is powered off. 2. GPS power control pin: used to control whether the internal parts of the GPS module have power to save electricity bills. 3. GSM antenna interface: GSM GPRS antenna, IPX-MINI antenna interface. > 4. DC-DC module: It adopts MSP series high-reliability power chip, and the power supply can be pin-out. 5. Main serial port and power supply pins: The serial port is compatible with 3.3V and 5V controllers, and supports mainstream 51 microcontrollers such as STM32. 6. Active GPS antenna, GPS antenna. It is an IPX-MINI type antenna interface. 7. Headphone interface: The microphone is used for welding voice interface, and the microphone can realize the function of mobile phone. (We have microphones and speakers for sale). 8. MICRO SIM card holder: Insert the SIM card directly. When the SIM card is missing from the punched hole, it supports various mobile phone cards of China Mobile and China Unicom. 5.