当前版本为1.5.3，原白板文件版本忘记了。
打开后只能看见连接线上的文字
使用记事本打开.canvas文件有如下内容：
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{“id”:“484dce28a4f5a924”,“type”:“text”,“text”:“串口初始化函数”,“x”:-825,“y”:1560,“width”:250,“height”:50,“color”:“3”},
{“id”:“fa64e8feaca8cdd8”,“type”:“text”,“text”:“HAL_UARTEx_RxEventCallback(huart, huart->RxXferSize)”,“x”:350,“y”:960,“width”:460,“height”:60},
{“id”:“7459d5f144537109”,“type”:“text”,“text”:“HAL_UART_Receive_IT(UART_HandleTypeDef \* huart, uint8_t \* pData, uint16_t Size\n- 设置接收类型为标准huart->ReceptionType = HAL_UART_RECEPTION_STANDARD;\n- 使能USART_CR1_RTOIE\n- 调用启动接收中断函数return (UART_Start_Receive_IT(huart, pData, Size));”,“x”:-1060,“y”:1170,“width”:680,“height”:146,“color”:“2”},
{“id”:“036a836aa8564606”,“type”:“file”,“file”:“通讯与外设/图片-uart/清除接收和空闲标志.png”,“x”:920,“y”:206,“width”:null,“height”:null},
{“id”:“c5459f76254cb873”,“type”:“text”,“text”:“HAL_UART_RxCpltCallback(huart)”,“x”:-70,“y”:960,“width”:300,“height”:60},
{“id”:“fc520c452f11520d”,“type”:“text”,“text”:“空闲检测\n判断是否启用空闲检测以及相应标志位\n
\nif ((huart- >ReceptionType== HAL_UART_RECEPTION_TOIDLE)\n\t&& ((isrflags & USART_ ISR_ IDLE) != 0U)\n\t&& ((cr1its & USART_ ISR_ IDLE ) != 0U) )\n\n如果nb_rx_data=huart->RxXferSize - huart->RxXferCount >0，则==清除使能==并调用回调函数\n\nHAL_UARTEx_ RxEventCallback(huart, nb_ rx__data);\n”,“x”:320,“y”:121,“width”:520,“height”:340},{“id”:“b592ee061b986c06”,“type”:“text”,“text”:“void HAL_UART_IRQHandler(UART_HandleTypeDef * huart)”,“x”:-160,“y”:-60,“width”:480,“height”:60},
{“id”:“49c46b636c642bc9”,“type”:“file”,“file”:“通讯与外设/图片-uart/HAL_UART_IRQHandler()调用回调函数.png”,“x”:-120,“y”:128,“width”:null,“height”:null},
{“id”:“512005191f1a6e01”,“type”:“text”,“text”:“UART_RxISR_8BIT(UART_HandleTypeDef * huart)\n- 从==DRD数据寄存器读数据到接收指针==，递增接收指针、递减剩余接收计数\n- 如果剩余接收计数为0，则==清除所有启用的标志位（中断失能）==\n\t- 启用了空闲检测，调用回调函数\n\tHAL_UARTEx_RxEventCallback(huart, huart->RxXferSize);\n\t- 否则，调用回调函数HAL_UART_RxCpltCallback(huart);”,“x”:-196,“y”:560,“width”:552,“height”:260},
{“id”:“8cca570cf68e8012”,“type”:“text”,“text”:“HAL\_StatusTypeDef UART_Start_Receive_IT(UART\_HandleTypeDef \huart, uint8\_t \pData, uint16\_t Size)\n- 接收指针、接收总数、剩余接收计数写入huart结构体\n- 设置状态为接收繁忙huart-> RxStateHAL_UART_STATE_BUSY_RX;\n- 设置回调函数huart->RxISR=UART_RxISR_8BIT;\n- 使能USART_CR1_PEIE | USART_CR1_RXNEIE\n\n\n",“x”:-1040,“y”:580,“width”:680,“height”:220},
{“id”:“4611d7f17ef2fc45”,“type”:“text”,“text”:"HAL_UART_ReceiveToIdle_IT(UART_HandleTypeDef \ huart, uint8_t \ pData, uint16_t Size\n- 设置接收类型为空闲huart->ReceptionType = HAL_UART_RECEPTION_IOIDLE;\n- 调用启动接收中断函数status = (UART_Start_Receive_IT(huart, pData, Size));\n- 使能USART_CR1_IDLEIE\n”,“x”:-1060,“y”:984,“width”:680,“height”:146,“color”:“2”},
{“id”:“da4d7beca86a8b8f”,“type”:“text”,“text”:“void USART_IRQHandler(void)”,“x”:-60,“y”:-200,“width”:280,“height”:60,“color”:“3”}
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