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Core/Src/main.c

@@ -126,7 +126,7 @@ int main(void)
   // __HAL_UART_ENABLE_IT(&huart2, UART_IT_IDLE);
 
   printf("USART2 DMA + IDLE 中断接收已启动\r\n");
-  uint8_t i = 0;
+  uint8_t i = 0xaa;
   /* USER CODE END 2 */
 
   /* Infinite loop */
@@ -145,8 +145,8 @@ int main(void)
     // memset(rx_buf, '\0', 500);
     // printf("%02X\r\n",i++);
     // printf("%d\r\n",strlen(msg));
-    HAL_UART_Transmit(&huart1, msg, strlen(msg), 100);
-    i++;
+    HAL_UART_Transmit(&huart1, &i, 1, 100);
+    // i++;
     HAL_Delay(1000);
     /* USER CODE BEGIN 3 */
   }