There is a high-level interface asyncio.create_subprocess_exec() that returns Process objects that allows to read a line asynchroniosly using StreamReader.readline() coroutine n_until_complete(loop.subprocess_exec(SubprocessProtocol, Loop = asyncio.ProactorEventLoop() # for subprocess' pipes on Windows The approach is similar to twisted-based answer by Ward - define a protocol and its methods are called as soon as data is ready: #!/usr/bin/env python3Ĭlass SubprocessProtocol(asyncio.SubprocessProtocol): Python 3.4 introduces new provisional API for asynchronous IO - asyncio module. ![]() In my opinion this is a bit cleaner than using the select or signal modules to solve this problem but then again it only works on UNIX. A solution I have found to this problem is to make stdin a non-blocking file using the fcntl module: import fcntlįcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK) If the primary functionality is complete and there is no longer any need to wait for further user input I typically want my program to exit, but it can't because readline() is still blocking in the other thread waiting for a line. Simply putting the user input handling functionality in another thread doesn't solve the problem because readline() blocks and has no timeout. We can use the same mbedRPC.py file as before.I have often had a similar problem Python programs I write frequently need to have the ability to execute some primary functionality while simultaneously accepting user input from the command line (stdin). Again guidelines for setting up mbed to use serial RPC can be found here: Interfacing-Using-RPC So if we set up mbed to receive RPC over serial then we can use this to control it. We know how to make Python talk to Serial. Or when on a Linux/unix system (in this case /dev/ttyACM0): #!python Or when on a Macintosh (in this case /dev/tty.usbmodem1912): #!python On Windows, connect to COM15 with default 9600 8N1 setting: #!python Python RPC via Serial ¶ Test the Serial Connection ¶ > x = DigitalOut(mbed, "led1") #pass in the name of that object you wish to write to > mbed = HTTPRPC("192.168.0.4")#IP address assigned to MBED when HTTP server is started The library is designed to be very similar to the mbed interface. ![]() Here is a Python RPC library which uses the mbed RPC mechanism to map Python classes on to the mbed Library C++ Interface classes. The mbed libraries support RPC, which means you can create objects and control them remotely Interfacing-Using-RPC. Also type ls /dev/ttyACM* to find the device name of the mbed USB serial connection.In a terminal type sudo easy_install pyserial to install PySerial.Python is most-likely already installed if not see your OS's install system or visit. ![]() Also type ls /dev/tty.usbmodem* to find the device name of the mbed USB serial connection.Run Terminal.app and type sudo easy_install pyserial at the prompt to install PySerial.Run pyserial-2.4.win32.exe - Python Serial Port Extension (gave some errors).Run pywin32-212.win32-py2.6.exe - Python Win32 Extensions.Run python-2.6.1.msi - Python Windows Binary.On windows, install python, win32 extensions and pyserial (if you want to communicate using serial): This page provides a library of code that can be used to communicate with mbed using RPC and a guide to set up Python. Python is one language which you may wish to use. There are many applications where you want to interface with mbed from a computer.
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