UART Communication Library

This UART communication library provides a reliable way to exchange data between two STM32 microcontrollers using UART. The library utilizes a custom protocol that includes:

• Start byte: Marks the beginning of the frame.
• Stop byte: Marks the end of the frame.
• Checksum: Ensures data integrity.
• Variable-length data: Supports sending frames of different sizes.
• ACK/NACK: Mechanism to confirm successful reception or request retransmission in case of errors.

Key Features

1. Start/Stop Bytes: Each frame starts with a special byte and ends with another, clearly marking the frame's boundaries.
2. Checksum: Verifies the integrity of transmitted data.
3. Variable-length Data: Supports different data sizes in the frames.
4. ACK/NACK: After receiving a frame, the receiver sends back an ACK (acknowledgment) or a NACK (negative acknowledgment).

Functions

1. UART_Protocol_Transmit_ByteByByte: Sends a data frame byte by byte.
2. UART_Protocol_Receive_IT: Receives data asynchronously via UART interrupts.
3. Checksum Calculation: Used to validate the data integrity.

How to Use the Library

Initialization

Before using the library, initialize the UART handle (e.g., huart2) in your main program.

Sending Data

You can send data using the UART_Protocol_Transmit_ByteByByte function:

uint8_t data[] = {0x01, 0x02, 0x03};  // Example data to send
UART_Protocol_Transmit_ByteByByte(&uartProtocolHandle, data, sizeof(data));

Receiving Data

To receive data, use the HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) function inside the UART interrupt handler. The received data is handled asynchronously.

Example:

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	if(huart == &huart2 ){
		UART_Protocol_Receive_IT(&uartProtocol);
		HAL_UART_Receive_IT(uartProtocol.huart, &uartProtocol.rxByte, 1);
	}
}

Handling Received Data

After receiving the data, check if it's ready using the isDataReady flag:

if (uartProtocolHandle.isDataReady) {
    // Process the received data
    uartProtocolHandle.isDataReady = 0;  // Reset the flag after processing
}