GD32F450 expansion board

 
     The GD32F450ZGT6 development board itself comes with a Dap download module, which integrates the download and serial port to facilitate downloading and debugging. However, this requires a new version of MDK to recognize, which is inconvenient for students who install the old version, so I combined the download interface with the serial port. They are all drawn out, making it easy to use STlink and Pwlink for downloading and debugging. It is convenient for learning about the development board, and four buttons and LEDs are introduced at the same time, giving more options for button lighting. However, because the pull-up resistor in the schematic diagram was not considered, button 1 cannot be used normally. For learning, you only need to solder the pin headers. As for the buttons and LEDs, they are dispensable. They are just for fun and testing. Overall, this board is very suitable for learning the GD32 development board. It should be noted that LED1 and LED2 are lit at low level, while LED3 and LED4 are on the contrary. The inputs of KEY1 and KEY2 are high level, and the inputs of KEY3 and KEY4 are low level. Due to the external pull-up of PC10, KEY1 cannot be used normally. I mainly tested the running water lamp, and there was no problem.