HK32F103CBT6A minimum development board system

Function description

A minimal development board system was designed using the domestic MCU HK32F103CBT6A, and the development board was used to implement the functions of OLED display, networking module MCU development solution, temperature and humidity sensor, and USB communication.

designing process

1. Component selection

1. I chose HK32F103CBT6A as the main control, taking this opportunity to understand the performance of the domestic Hangshun MCU and explore the differences with the STM32F103 series (STM32 is getting more and more expensive).
2. The voltage regulator chip uses the popular AMS1117-3.3, which can reach up to 1A, meeting the general requirements of the smallest system.
3. Adopt the now popular Type-C interface.
4. Use sht30 as a temperature and humidity sensor, and use redundant networking modules to expand WIFI functions.

2. PCB design

PCB design adopts the form of minimum core board + expansion board. The left side is the expansion board. Connect BOOT0 to GND on the expansion board. HK32 can be booted from FLASH. There is also a Tuya WBR3 networking module and SHT30 sensor on the board, which can be spliced ​​to the development board for use or used on other boards. At the same time, there is a 0 ohm resistor pad left, and the module can be used alone. The right side is the core board. The components are compactly placed. The 3v3 power supply line width is 1.2mm to ensure the power supply of the chip. At the same time, on the D+ signal transmission line Pulled up with a 1.5k ohm resistor.

Soldered circuit board

3. Procedure

• [x] OLED display
• [x] SHT30 temperature and humidity sensor
• [ ] USB communication
• [x] Networking module

1. OLED display

The OLED display works fine.

2. SHT30 temperature and humidity sensor

Since the pin issue was not considered during the design, the Tuya USART3 pin conflicts with the I2C2 pin, and OLED cannot be used to display temperature and humidity data. (Newbie Xiaobai, after making the board, I learned that the I2C bus can control sensors with different addresses. When the addresses are the same, they can be addressed by turning on and off power or transmission lines. Here, the SHT30 temperature and humidity sensor address (0x44), OLED (0x78), It can be controlled with the same I2C bus, you can try it next time) I will add later that the SHT30 temperature and humidity sensor works normally.

3. USB communication

The USB communication code is relatively complex and I am still learning. I will add it later.

4. Tuya networking module

In the test assistant, the MCU has successfully configured the networking module, but since the module is still on the way, it can only be added later. By comparing HKF103 and STM32F103, we found that the USART data register of HK in the code is different from that of STM32. HK is a shared DR for Send and Receive, while STM32 uses TDR and RDR respectively. Similarly, the ISR of STM32 changes to SR in HK. You have to read and compare the library code to find out when the code is transplanted.

Attached is the github address: https://github.com/594642987/HK32F103CBT6A-Mini-Bored-System