Before Mashing the Keyboard

1. This project uses FreeRTOS.

2. To add functions, first make changes in FreeRTOS_USB_USART_Echo.ioc using STM32CubeMX, i.e. add a task (FreeRTOS terminology), then generate code using STM32CubeMX, edit the code in Keil uvision, compile and flash the development board.

3. Having only one dev board will work. You should see all the desired behaviour outline in the Commands You Can Play With & Observations section.

4. To work with two-board communication, you need two dev boards.

Getting Started

1. Compile the code.

2. Download the code to the development board(s).

3. Use a micro USB cable to connect the development board and your computer.

4. Optional: if you have two boards:

   1. Connect one board to the computer via USB.

   2. Connect the two board on their USART 6 ports. Note:

      Pin on dev board A	Pin on dev board B
      RX	TX
      TX	RX
      GND	GND

   3. DO NOT CONNECT THE VCC PINS ON BOTH DEV BOARDS TOGETHER!

5. Identify the COM/serial port that identifies the development board. On Windows, you can use Device Manager.

6. Install Putty. Use the following pictures to change Putty settings.

   Set the communication parameters:

   

   Set the display parameters:

   

Commands You Can Play With & Observations

With 1 dev board

1. Any string starts with q. The response will be you typed q\r\n.

2. Any string starts with w. The response will be you typed w\r\n.

3. For any other strings, the response will repeat what you have sent over USB.

Only with 2 dev boards

Regardless of whether sening strings or not, or the content of the string, one green LED light will turn on and off every second on each board.

How to Use USB in Your Code

1. For modifying the behaviour when receiving data on the USB CDC interface, edit the CDC_Receive_FS function in usbd_cdc_if.c.

2. For sending data from the USB CDC interface, do

   #include "usbd_cdc_if.h"

   to include the necessary header, then do

   uint8_t Buffer[] = ...;
   CDC_Transmit_FS(Buffer, sizeof(Buffer));		

   Buffer is the uint8_t array that holds the data for sending.

Happy hacking!