[Internet of Things] WiFi smart switch +493425S based on Hongmeng IoT

# Using HiSilicon Hi3861 SoC module and WiFi smart switch made by ohos### 1. Physical picture: ##### Front of the board: ![Front.jpg] ##### Back of the board: ![Back .jpg] ##### Only using battery power supply: ![Battery voltage.jpg] ##### When Type-C power supply and battery charging: ![Charging.jpg] ### 2. Completion status: ## ### Realized: The board has been physically welded and developed using Yuanqipai’s source code; buzzers, relays, buttons, and LEDs can all be controlled normally; battery voltage ADCs and photoresistor ADCs can both be used; PWM can be output normally, But it can only output a frequency above 2.4kHz; 0.96-inch OLED, driven by I2C, can display normally; the relay can be controlled on and off by judging the voltage value of the photoresistor; when only lithium battery is used for power supply, use the IO port to control the IP5306 The KEY pin allows the IP5306 to normally output 5V under small loads; ##### To be implemented: Communicate with DHT11 to read temperature and humidity; Use GPIO to simulate PWM to control the servo; Allow the device to connect to the cloud platform, etc.; ## # 3. Current problems: 3.1. Using the GPIO of the module to communicate with DHT11 via a single bus always fails and cannot communicate with DHT11. The reason has not been found yet; 3.2. Under C language development, use the GPIO of the module to simulate PWM control. The servo can only be turned to a fixed position and cannot be controlled to other positions. However, it can be controlled normally under micropython as in the video. I don’t know why for the time being; 3.3. As shown below, when the USB power supply is unplugged, VBAT It will pour back, and I haven't found the reason yet; I first removed R1, Q3, and U3 in the picture, and used an SS34 in series with the circuit. However, when powered by VBUS, the voltage drop of the diode is about 0.3V. ![image.png]