我在用ros-noetic的时候，在ros-arduino-bridge改完之后，和我的mega2560准备进行连接，但是在我运行roslaunch ros_arduino_python arduino.launch之后，mega2560一直和树莓派连接不上，一直在获取波特率那里显示错误，但是我已经检查过了，波特率是没有问题的
NODES
arduino （ros arduino python/arduino node.py）
auto-startingnew master
processtmaster]:started with pid 35217
ROSMASTERURI=http://192.168.43.128:11311
setting/runidtob716a008-70eb-11ef-be47-8fba38983800
process[rosout-1]:startedwith pid [3531]
started core service/rosout
process[arduino-2]:startedwithpid [3538]
Connecting to Arduino on port/dev/ttyUSB0
Exceptionexecutingcommand:b
Exception executingcommand:b
Serial Exception:
（<classserial.serialutil.SerialException'>，SerialException(），<traceback object at 0xffff81e22200>）
Tracebackfollows:
Traceback（mostrecent call last）:
File "/home/pi/catkin ws/src/ros_arduino bridge_copy/ros_arduino python/src/ros_arduino python/arduino_driver·py"， Line 75
in connect
raise SerialException
serial.serialutil.SerialException
Cannot connect toArduino！
Larduino-2] process has died [pid 3538,exit code 1，cmd /home/pi/catkin ws/src/ros arduino bridge_copy/ros arduino python/nod
es/arduino node.py name:=arduinotog:=/home/pi/.ros/log/b716a008-70eb-11ef-be47-8fba3898380c/arduino-2.1og]
Logfile:/home/pi/.ros/log/b716a008-70eb-11ef-be47-8fba3898380c/arduino-2*.og
我已经检查很久都找不出问题了，恳请各位佬能够帮我解决
