Simple PySerial-based terminal emulator

terminal.py

@@ -0,0 +1,112 @@
+#!/usr/bin/python
+# Based on miniterm sample in pyserial
+
+import sys, os, serial, threading
+
+if os.name == 'nt':
+    import msvcrt
+    class Console:
+        def __enter__(self):
+            return self
+        def __exit__(self, type, value, traceback):
+            pass
+        def getkey(self):
+            while 1:
+                z = msvcrt.getch()
+                if z == '\0' or z == '\xe0': # function keys
+                    msvcrt.getch()
+                else:
+                    if z == '\r':
+                        return '\n'
+                    return z
+elif os.name == 'posix':
+    import termios, sys, os
+    class Console:
+        def __enter__(self):
+            self.fd = sys.stdin.fileno()
+            self.old = termios.tcgetattr(self.fd)
+            new = termios.tcgetattr(self.fd)
+            new[3] = new[3] & ~termios.ICANON & ~termios.ECHO & ~termios.ISIG
+            new[6][termios.VMIN] = 1
+            new[6][termios.VTIME] = 0
+            termios.tcsetattr(self.fd, termios.TCSANOW, new)
+            return self
+        def __exit__(self, type, value, traceback):
+            termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.old)
+        def getkey(self):
+            c = os.read(self.fd, 1)
+            return c
+else:
+    raise "Sorry, no terminal implementation for your platform (%s) available." % sys.platform
+
+class Miniterm:
+    def __init__(self, serial):
+        self.serial = serial
+
+    def start(self):
+        self.alive = True
+        #start serial->console thread
+        self.receiver_thread = threading.Thread(target=self.reader)
+        self.receiver_thread.setDaemon(1)
+        self.receiver_thread.start()
+        #enter console->serial loop
+        self.transmitter_thread = threading.Thread(target=self.writer)
+        self.transmitter_thread.setDaemon(1)
+        self.transmitter_thread.start()
+
+    def stop(self):
+        self.alive = False
+
+    def join(self, transmit_only=False):
+        self.transmitter_thread.join()
+        if not transmit_only:
+            self.receiver_thread.join()
+
+    def reader(self):
+        """loop and copy serial->console"""
+        while self.alive:
+            data = self.serial.read(1)
+            if data == '\r':
+                sys.stdout.write('\n')
+            else:
+                sys.stdout.write(data)
+            sys.stdout.flush()
+
+    def writer(self):
+        """loop and copy console->serial until ^C"""
+        with Console() as console:
+            while self.alive:
+                try:
+                    c = console.getkey()
+                except KeyboardInterrupt:
+                    c = '\x03'
+                if c == '\x03':
+                    self.stop()
+                    break                                   # exit app
+                elif c == '\x00':
+                    # don't write null, that will stop the other end
+                    pass
+                else:
+                    self.serial.write(c)                    # send character
+
+    def run(self):
+        saved_timeout = self.serial.timeout
+        self.serial.timeout = 0.1
+        self.start()
+        self.join(True)
+        self.join()
+        self.serial.write('\x00')
+        self.serial.timeout = saved_timeout
+
+if __name__ == "__main__":
+    import argparse
+
+    parser = argparse.ArgumentParser(description="Simple serial terminal")
+    parser.add_argument('device', metavar='DEVICE',
+                        help='serial device')
+    parser.add_argument('baudrate', metavar='BAUDRATE', type=int, nargs='?',
+                        help='baud rate', default=115200)
+    args = parser.parse_args()
+    term = Miniterm(serial.Serial(args.device, args.baudrate))
+    term.run()
+