在树莓派的8和10管脚上插了一个由串口输出结果的激光传感器，然后Mu上编程读取串口数据，

程序如下：
import serial
import time

ser = serial.Serial('/dev/ttyS0',230400)

while True:
ser.readline()
time.sleep(1)

运行后提示：

Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/serial/serialposix.py", line 322, in open
self.fd = os.open(self.portstr, os.O_RDWR | os.O_NOCTTY | os.O_NONBLOCK)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
PermissionError: [Errno 13] Permission denied: '/dev/ttyS0'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/rancho/programs/jiguang.py", line 4, in <module>
ser = serial.Serial('/dev/ttyS0',230400)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3/dist-packages/serial/serialutil.py", line 244, in __init__
self.open()
File "/usr/lib/python3/dist-packages/serial/serialposix.py", line 325, in open
raise SerialException(msg.errno, "could not open port {‌}: {‌}".format(self._port, msg))
serial.serialutil.SerialException: [Errno 13] could not open port /dev/ttyS0: [Errno 13] Permission denied: '/dev/ttyS0'

看提示是说没有权限访问串口，按照教程

https://blog.csdn.net/qq_40342287/article/details/105939584?spm=1001.2101.3001.6650.17&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-17-105939584-blog-128244634.235%5Ev40%5Epc_relevant_anti_t3_base&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7ERate-17-105939584-blog-128244634.235%5Ev40%5Epc_relevant_anti_t3_base

设置后还是不行