按下或释放键盘键时写入串行

Question

I am writing a Python script that will talk to an Arduino using serial. The Arduino will implement a simple musical keyboard.

So the desired behavior is:

• When I press a key on my PC keyboard, some byte is sent over serial;
• While I keep the key pressed, nothing is sent;
• When I release that key, another given byte is sent.

Answer 1

For single character input from the keyboard read this article .

If you really want to get gritty, it's better to make a small GUI with pygtk or so. There you have easy access to keypress, keyrelease events. It can be done with very little code.

On the serial port side, PySerial comes to mind - this makes it easier to change the baudrate etc. to adapt to the Arduino.

Are you trying to send MIDI commands?

import pygtk
import gtk

class MainWindow(gtk.Window):
    def __init__(self, debug = None):
        gtk.Window.__init__(self)
        self.connect("delete-event", self.on_delete_event)
        self.set_size_request(400, 300)

        bff = gtk.TextBuffer()
        self.txtview = gtk.TextView(bff)
        self.add(self.txtview)

        self.connect("key-press-event", self.on_key_press)
        self.connect("key-release-event", self.on_key_release)

    def on_key_press(self, key, event):
        # Send something
        print("Key pressed")
        pass

    def on_key_release(self, key, event):
        # Send something
        print("Key released")
        pass

    def on_delete_event(self, win, data):
        gtk.main_quit()

    def run(self):
        self.show_all()
        gtk.mainloop()



def main():
    # Do you PySerial initializing here
    w = MainWindow()
    w.run()
    return 0

if __name__ == '__main__':
    main()