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我有一個python程序，我正在使用它來與一個微控制器交談。它打開了COM端口是這樣的：爲什麼我的COM端口很忙？
def STM32_connect():
ports = list(serial.tools.list_ports.comports())
for p in ports:
if "STM32" in p.description:
connection = serial.Serial(p.device, timeout = .01)
return(connection)
print("ERROR: No STM32 Device Found")
sys.exit()
serial_connection = STM32_connect()
然後做了一堆東西，發送和接收數據，直到我關閉程序像這樣用鍵盤interput：
except:
print("\n Program Interrupted...")
finally:
print("\n Closing Serial Port\n")
serial_connection.close()
這一切工作正常。我的問題是，當python腳本通過斷開USB電纜或關閉電路板而無法正常工作時，我無法再連接到任何COM端口上的micro。我收到此錯誤：
Traceback (most recent call last):
File "/home/---/.local/lib/python3.5/site-packages/serial/serialposix.py", line 265, in open
self.fd = os.open(self.portstr, os.O_RDWR | os.O_NOCTTY | os.O_NONBLOCK)
OSError: [Errno 16] Device or resource busy: '/dev/ttyACM2'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "flextester.py", line 1, in <module>
from flex_usb_class import *
File "/home/---/Code/RobotFlexTester/flex_usb_class.py", line 30, in <module>
serial_connection = STM32_connect()
File "/home/---/Code/RobotFlexTester/flex_usb_class.py", line 25, in STM32_connect
connection = serial.Serial(p.device, timeout = .01)
File "/home/---/.local/lib/python3.5/site-packages/serial/serialutil.py", line 240, in __init__
self.open()
File "/home/janey/.local/lib/python3.5/site-packages/serial/serialposix.py", line 268, in open
raise SerialException(msg.errno, "could not open port {}: {}".format(self._port, msg))
serial.serialutil.SerialException: [Errno 16] could not open port /dev/ttyACM2: [Errno 16] Device or resource busy: '/dev/ttyACM2'
我可以改變COM端口和我收到完全相同的錯誤在不同ttyACM端口。但是如果我嘗試運行不同的python腳本，我可以連接到同一端口上的相同設備。問題似乎以某種方式被鎖定到初始測試腳本，但ps -a未顯示它仍然在運行。大約30秒後 - 1分鐘後，問題就消失了。