On the back of the cardboard in the package of this kit, there is a text "Getting started" which introduces the demo that comes with the development board (already burned in). If I hadn't seen the post by netizen damiaa saying this, I would have ignored it. When I plugged the USB Dongle into the computer, I didn't install the virtual serial port driver, so I didn't know what the default program was (I thought it was a sniffer). If you don't have a virtual serial port, you can download this:
stmcdc.zip
(5.41 KB, downloads: 14)
However, the program on Nucleo does not use the virtual serial port. It uses UART to output information through the virtual serial port of ST-Link v2. So the USB cable can only be plugged into the port of ST-Link. The Nucleo board is a server and starts broadcasting after power-on. The Dongle is a client. You can press the button above to automatically scan and connect. More details can be seen in the serial terminal (baud 115200, 8-N-1 format)
After the connection is established, SW1 on both boards can control the blue LED of the other party. SW2 on the Nucleo can switch the BLE connection interval, and the flashing green LED will follow this interval. This can be felt from the delay in controlling the LED state. Without using a USB dongle, you can use a BLE-enabled mobile phone to obtain information about the Nucleo board. It has two Primary Services (all BLE devices have) and one Custom Service:
The LED control is in this custom service:
Among them, the second characteristic with notification function is to receive SW1 key information. When SW1 is pressed, the value displayed on the mobile phone will also change. The first characteristic can change the state of the blue LED on the nucleo by writing a value. The third one, guess what it does...
提升卡
变色卡
千斤顶