Added script which sends its stdin to serial

* It groups its input into batches of 3*(# of boxes) bytes

host_python/send_to_serial.py

@@ -0,0 +1,70 @@
+#!/usr/bin/python
+# vim:et:sw=4:ts=4:sts=4
+
+import sys
+import serial
+import getopt
+
+def print_usage():
+    print '''\
+USAGE:
+    %s [-h | [-n number] [-b speed] serial]
+OPTIONS:
+    serial          write output to serial device
+    -b speed        speed of the serial device
+    -n number       number of controlled boxes
+    -h --help       show this help
+''' % sys.argv[0]
+
+def main():
+    try:
+        opts, args = getopt.getopt(sys.argv[1:], 's:b:n:h', ['help'])
+    except getopt.GetOptError:
+        print_usage()
+        return 1
+    speed = 38400
+    number = 10
+    show_help = False
+    for k, v in opts:
+        if k == '-n':
+            if not v.isdigit():
+                print_usage()
+                return 1
+            number = int(v)
+        elif k == '-b':
+            if not v.isdigit():
+                print_usage()
+                return 1
+            speed = int(v)
+        elif k == '-h' or k == '--help': show_help = True
+    if show_help:
+        print_usage()
+        return 0
+    if len(args) != 1:
+        print_usage()
+        return 1
+
+    try:
+        output_stream = serial.Serial(args[0], speed)
+    except serial.serialutil.SerialException:
+        print 'Could not open the serial device'
+        return 1
+
+    try:
+        while True:
+            data = ''
+            to_read = number*3
+            while to_read > 0:
+                read = sys.stdin.read(to_read)
+                if len(read) == 0: break
+                to_read -= len(read)
+                data += read
+            if len(read) == 0: break
+            output_stream.write(data)
+            output_stream.flush()
+    except IOError:
+        pass
+
+    return 0
+
+sys.exit(main())