问题
While connecting my Com-port using matlab, many a times(4 out of 5) I get an error
??? Error using ==> serial.fopen at 72
Port: COM21 is not available. Available ports: COM3,
COM10, COM17, COM18.
However , sometimes it gets connected and responds as expected. Can anyone tell me whats the problem with this?
By the way , I am using this snippet to connect my microcontroller to PC through USB
s = serial('COM21'); // code to initialize the req COM i.e. COM21 for me
fopen(s);
回答1:
I ran into this issue before. It turns out MATLAB doesn't really handle plug-and-play very well, as evidenced by this thread:
http://www.mathworks.com/matlabcentral/newsreader/view_thread/311133
Long story short: if you want MATLAB to detect a hardware change, you need to restart it. MATLAB seems to only look for devices when it starts up.
来源：https://stackoverflow.com/questions/6321349/virtual-com-port-communication-through-matlab