Merge git.sugarlabs.org:~walter/turtleart/collaboration-refactoring

Conflicts:
	NEWS
	TurtleArt/talogo.py

8 files changed, 679 insertions, 0 deletions

diff --git a/plugins/__init__.py b/plugins/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/plugins/__init__.py
diff --git a/plugins/__init__.pyc b/plugins/__init__.pyc
new file mode 100644
index 0000000..ce06608
--- /dev/null
+++ b/plugins/__init__.pyc
diff --git a/plugins/audio_sensors_plugin.py b/plugins/audio_sensors_plugin.py
new file mode 100644
index 0000000..d8908c8
--- /dev/null
+++ b/plugins/audio_sensors_plugin.py
@@ -0,0 +1,272 @@
+#!/usr/bin/env python
+#Copyright (c) 2011 Walter Bender
+
+#Permission is hereby granted, free of charge, to any person obtaining a copy
+#of this software and associated documentation files (the "Software"), to deal
+#in the Software without restriction, including without limitation the rights
+#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#copies of the Software, and to permit persons to whom the Software is
+#furnished to do so, subject to the following conditions:
+
+#The above copyright notice and this permission notice shall be included in
+#all copies or substantial portions of the Software.
+
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+#THE SOFTWARE.
+
+import gst
+try:
+    from numpy import append
+    from numpy.fft import rfft
+    PITCH_AVAILABLE = True
+except:
+    PITCH_AVAILABLE = False
+import gtk
+
+from gettext import gettext as _
+
+from plugin import Plugin
+
+from audio.audiograb import AudioGrab_Unknown, AudioGrab_XO1, AudioGrab_XO15, \
+    SENSOR_DC_NO_BIAS, SENSOR_DC_BIAS
+
+from audio.ringbuffer import RingBuffer1d
+
+from TurtleArt.taconstants import PALETTES, PALETTE_NAMES, BOX_STYLE_MEDIA, \
+    CONTENT_BLOCKS, BLOCK_NAMES, DEFAULTS, SPECIAL_NAMES, HELP_STRINGS, \
+    BOX_STYLE, PRIMITIVES, XO1, XO15
+from TurtleArt.talogo import VALUE_BLOCKS, PLUGIN_DICTIONARY
+from TurtleArt.tautils import get_path
+
+import logging
+_logger = logging.getLogger('turtleart-activity audio sensors plugin')
+
+
+def _avg(array, abs_value=False):
+    """ Calc. the average value of an array """
+    if len(array) == 0:
+        return 0
+    array_sum = 0
+    if abs_value:
+        for a in array:
+            array_sum += abs(a)
+    else:
+        for a in array:
+            array_sum += a
+    return float(array_sum) / len(array)
+
+
+class Audio_sensors_plugin(Plugin):
+
+    def __init__(self, parent):
+        self._parent = parent
+        self.hw = self._parent.hw
+        self._status = True  # TODO: test for audio device
+
+    def setup(self):
+        # set up audio-sensor-specific blocks
+        if not self._status:
+            return
+
+        self.max_samples = 1500
+        self.input_step = 1
+
+        self.ringbuffer = RingBuffer1d(self.max_samples, dtype='int16')
+        if self.hw == XO1:
+            self.voltage_gain = 0.00002225
+            self.voltage_bias = 1.140
+        elif self.hw == XO15:
+            self.voltage_gain = -0.0001471
+            self.voltage_bias = 1.695
+
+        PALETTES[PALETTE_NAMES.index('sensor')].append('sound')
+        BOX_STYLE.append('sound')
+        BLOCK_NAMES['sound'] = [_('sound')]
+        HELP_STRINGS['sound'] = _('raw microphone input signal')
+        VALUE_BLOCKS.append('sound')
+        PRIMITIVES['sound'] = 'sound'
+        PLUGIN_DICTIONARY['sound'] = self.prim_sound
+        self._parent.lc._def_prim('sound', 0,
+            lambda self: PLUGIN_DICTIONARY['sound']())
+        PALETTES[PALETTE_NAMES.index('sensor')].append('volume')
+        BOX_STYLE.append('volume')
+        BLOCK_NAMES['volume'] = [_('volume')]
+        HELP_STRINGS['volume'] = _('microphone input volume')
+        VALUE_BLOCKS.append('volume')
+        PRIMITIVES['volume'] = 'volume'
+        PLUGIN_DICTIONARY['volume'] = self.prim_volume
+        self._parent.lc._def_prim('volume', 0,
+            lambda self: PLUGIN_DICTIONARY['volume']())
+        PALETTES[PALETTE_NAMES.index('sensor')].append('pitch')
+        BOX_STYLE.append('pitch')
+        BLOCK_NAMES['pitch'] = [_('pitch')]
+        HELP_STRINGS['pitch'] = _('microphone input pitch')
+        VALUE_BLOCKS.append('pitch')
+        PRIMITIVES['pitch'] = 'pitch'
+        PLUGIN_DICTIONARY['pitch'] = self.prim_pitch
+        self._parent.lc._def_prim('pitch', 0,
+            lambda self: PLUGIN_DICTIONARY['pitch']())
+
+        if self.hw in [XO1, XO15]:
+            PALETTES[PALETTE_NAMES.index('sensor')].append('resistance')
+            BOX_STYLE.append('resistance')
+            BLOCK_NAMES['resistance'] = [_('resistance')]
+            HELP_STRINGS['resistance'] = _('sensor input resistance')
+            VALUE_BLOCKS.append('resistance')
+            PRIMITIVES['resistance'] = 'resistance'
+            PLUGIN_DICTIONARY['resistance'] = self.prim_resistance
+            self._parent.lc._def_prim('resistance', 0,
+                lambda self: PLUGIN_DICTIONARY['resistance']())
+
+            PALETTES[PALETTE_NAMES.index('sensor')].append('voltage')
+            BOX_STYLE.append('voltage')
+            BLOCK_NAMES['voltage'] = [_('voltage')]
+            HELP_STRINGS['voltage'] = _('sensor voltage')
+            VALUE_BLOCKS.append('voltage')
+            PRIMITIVES['voltage'] = 'voltage'
+            PLUGIN_DICTIONARY['voltage'] = self.prim_voltage
+            self._parent.lc._def_prim('voltage', 0,
+                lambda self: PLUGIN_DICTIONARY['voltage']())
+        self.audio_started = False
+
+    def start(self):
+        # This gets called by the start button
+        if not self._status:
+            return
+        """ Start grabbing audio if there is an audio block in use """
+        if len(self._parent.block_list.get_similar_blocks('block',
+            ['volume', 'sound', 'pitch', 'resistance', 'voltage'])) > 0:
+            if self.audio_started:
+                self.audiograb.resume_grabbing()
+            else:
+                if self.hw == XO15:
+                    self.audiograb = AudioGrab_XO15(self.new_buffer, self)
+                elif self.hw == XO1:
+                    self.audiograb = AudioGrab_XO1(self.new_buffer, self)
+                else:
+                    self.audiograb = AudioGrab_Unknown(self.new_buffer, self)
+                self.audiograb.start_grabbing()
+                self.audio_started = True
+        self._update_audio_mode()
+
+    def new_buffer(self, buf):
+        """ Append a new buffer to the ringbuffer """
+        self.ringbuffer.append(buf)
+        return True
+
+    def _update_audio_mode(self):
+        """ If there are sensor blocks, set the appropriate audio mode """
+        if not hasattr(self._parent.lc, 'value_blocks'):
+            return
+        for name in ['sound', 'volume', 'pitch']:
+            if name in self._parent.lc.value_blocks:
+                if len(self._parent.lc.value_blocks[name]) > 0:
+                    self.audiograb.set_sensor_type()
+                    return
+        if 'resistance' in self._parent.lc.value_blocks:
+            if len(self._parent.lc.value_blocks['resistance']) > 0:
+                self.audiograb.set_sensor_type(SENSOR_DC_BIAS)
+                return
+        if 'voltage' in self._parent.lc.value_blocks:
+            if len(self._parent.lc.value_blocks['voltage']) > 0:
+                self.audiograb.set_sensor_type(SENSOR_DC_NO_BIAS)
+                return
+
+    def stop(self):
+        # This gets called by the stop button
+        if self._status:
+            if self.audio_started:
+                self.audiograb.pause_grabbing()
+
+    def goto_background(self):
+        # This gets called when your process is sent to the background
+        pass
+
+    def return_to_foreground(self):
+        # This gets called when your process returns from the background
+        pass
+
+    def quit(self):
+        # This gets called by the quit button
+        self.stop()
+
+    def _status_report(self):
+        print 'Reporting audio sensor status: %s' % (str(self._status))
+        return self._status
+
+    # Block primitives used in talogo
+
+    def prim_volume(self):
+        """ return mic in value """
+        #TODO: Adjust gain for different HW
+        buf = self.ringbuffer.read(None, self.input_step)
+        if len(buf) > 0:
+            volume = float(_avg(buf, abs_value=True))
+            self._parent.lc.update_label_value('volume', volume)
+            return volume
+        else:
+            return 0
+
+    def prim_sound(self):
+        """ return raw mic in value """
+        buf = self.ringbuffer.read(None, self.input_step)
+        if len(buf) > 0:
+            sound = float(buf[0])
+            self._parent.lc.update_label_value('sound', sound)
+            return sound
+        else:
+            return 0
+
+    def prim_pitch(self):
+        """ return index of max value in fft of mic in values """
+        if not PITCH_AVAILABLE:
+            return 0
+        buf = []
+        for i in range(4):
+            buf = append(buf, self.ringbuffer.read(None, self.input_step))
+        if len(buf) > 0:
+            r = []
+            for j in rfft(buf):
+                r.append(abs(j))
+            # Convert output to Hertz
+            pitch = r.index(max(r)) * 48000 / len(buf)
+            self._parent.lc.update_label_value('pitch', pitch)
+            return pitch
+        else:
+            return 0
+
+    def prim_resistance(self):
+        """ return resistance sensor value """
+        buf = self.ringbuffer.read(None, self.input_step)
+        if len(buf) > 0:
+            # See <http://bugs.sugarlabs.org/ticket/552#comment:7>
+            # TODO: test this calibration on XO 1.5
+            if self.hw == XO1:
+                resistance = 2.718 ** ((float(_avg(buf)) * 0.000045788) + \
+                                           8.0531)
+            else:
+                avg_buf = float(_avg(buf))
+                if avg_buf > 0:
+                    resistance = (420000000 / avg_buf) - 13500
+                else:
+                    resistance = 420000000
+            self._parent.lc.update_label_value('resistance', resistance)
+            return resistance
+        else:
+            return 0
+
+    def prim_voltage(self):
+        """ return voltage sensor value """
+        buf = self.ringbuffer.read(None, self.input_step)
+        if len(buf) > 0:
+            # See <http://bugs.sugarlabs.org/ticket/552#comment:7>
+            voltage = float(_avg(buf)) * self.voltage_gain + self.voltage_bias
+            self._parent.lc.update_label_value('voltage', voltage)
+            return voltage
+        else:
+            return 0
diff --git a/plugins/camera_plugin.py b/plugins/camera_plugin.py
new file mode 100644
index 0000000..3061d39
--- /dev/null
+++ b/plugins/camera_plugin.py
@@ -0,0 +1,190 @@
+#!/usr/bin/env python
+#Copyright (c) 2011 Walter Bender
+
+#Permission is hereby granted, free of charge, to any person obtaining a copy
+#of this software and associated documentation files (the "Software"), to deal
+#in the Software without restriction, including without limitation the rights
+#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#copies of the Software, and to permit persons to whom the Software is
+#furnished to do so, subject to the following conditions:
+
+#The above copyright notice and this permission notice shall be included in
+#all copies or substantial portions of the Software.
+
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+#THE SOFTWARE.
+
+import gst
+import gtk
+from fcntl import ioctl
+
+from gettext import gettext as _
+
+from camera.tacamera import Camera
+from camera.v4l2 import v4l2_control, V4L2_CID_AUTOGAIN, VIDIOC_G_CTRL, \
+ VIDIOC_S_CTRL
+
+from plugin import Plugin
+from TurtleArt.taconstants import PALETTES, PALETTE_NAMES, BOX_STYLE_MEDIA, \
+    CONTENT_BLOCKS, BLOCK_NAMES, DEFAULTS, SPECIAL_NAMES, HELP_STRINGS, \
+    BOX_STYLE, PRIMITIVES
+from TurtleArt.talogo import VALUE_BLOCKS, MEDIA_BLOCKS_DICTIONARY, \
+    PLUGIN_DICTIONARY
+from TurtleArt.tautils import get_path
+
+import logging
+_logger = logging.getLogger('turtleart-activity camera plugin')
+
+
+class Camera_plugin(Plugin):
+
+    def __init__(self, parent):
+        self._parent = parent
+        self._status = False
+
+        v4l2src = gst.element_factory_make('v4l2src')
+        if v4l2src.props.device_name is not None:
+
+            if self._parent.running_sugar:
+                self._imagepath = get_path(self._parent.activity,
+                                          'data/turtlepic.png')
+            else:
+                self._imagepath = '/tmp/turtlepic.png'
+            self._camera = Camera(self._imagepath)
+
+            self._status = True
+
+    def setup(self):
+        # set up camera-specific blocks
+        if self._status:
+            PALETTES[PALETTE_NAMES.index('sensor')].append('luminance')
+            BOX_STYLE.append('luminance')
+            BLOCK_NAMES['luminance'] = [_('brightness')]
+            HELP_STRINGS['luminance'] = _("light level detected by camera")
+            VALUE_BLOCKS.append('luminance')
+            PRIMITIVES['luminance'] = 'luminance'
+            PLUGIN_DICTIONARY['luminance'] = self.prim_read_camera
+            self._parent.lc._def_prim('luminance', 0,
+                lambda self: PLUGIN_DICTIONARY['luminance'](True))
+
+            # Depreciated block
+            BOX_STYLE.append('readcamera')
+            BLOCK_NAMES['readcamera'] = [_('read camera')]
+            HELP_STRINGS['readcamera'] = \
+                _("Average RGB color from camera is pushed to the stack")
+            VALUE_BLOCKS.append('readcamera')
+            PRIMITIVES['readcamera'] = 'readcamera'
+            PLUGIN_DICTIONARY['readcamera'] = self.prim_read_camera
+            self._parent.lc._def_prim('readcamera', 0,
+                lambda self: PLUGIN_DICTIONARY['readcamera'](True))
+
+            PALETTES[PALETTE_NAMES.index('sensor')].append('camera')
+            BOX_STYLE_MEDIA.append('camera')
+            CONTENT_BLOCKS.append('camera')
+            BLOCK_NAMES['camera'] = [' ']
+            DEFAULTS['camera'] = ['CAMERA']
+            SPECIAL_NAMES['camera'] = _('camera')
+            HELP_STRINGS['camera'] = _('camera output')
+            MEDIA_BLOCKS_DICTIONARY['camera'] = self.prim_take_picture
+
+    def start(self):
+        # This gets called by the start button
+        pass
+
+    def stop(self):
+        # This gets called by the stop button
+        if self._status:
+            self._camera.stop_camera_input()
+
+    def goto_background(self):
+        # This gets called when your process is sent to the background
+        pass
+
+    def return_to_foreground(self):
+        # This gets called when your process returns from the background
+        pass
+
+    def quit(self):
+        # This gets called by the quit button
+        pass
+
+    def _status_report(self):
+        print 'Reporting camera status: %s' % (str(self._status))
+        return self._status
+
+    # Block primitives used in talogo
+
+    def prim_take_picture(self):
+        if self._status:
+            ''' method called by media block '''
+            self._camera.save_camera_input_to_file()
+            self._camera.stop_camera_input()
+            self._parent.lc.filepath = self._imagepath
+
+    def prim_read_camera(self, luminance_only=False):
+        """ Read average pixel from camera and push b, g, r to the stack """
+        pixbuf = None
+        array = None
+        w, h = self._parent.lc._w(), self._parent.lc._h()
+        if w > 0 and h > 0 and self._status:
+            try:
+                self._video_capture_device = open('/dev/video0', 'rw')
+            except:
+                self._video_capture_device = None
+                _logger.debug('video capture device not available')
+
+            if self._video_capture_device is not None:
+                self._ag_control = v4l2_control(V4L2_CID_AUTOGAIN)
+                try:
+                    ioctl(self._video_capture_device, VIDIOC_G_CTRL,
+                          self._ag_control)
+                    self._ag_control.value = 0  # disable AUTOGAIN
+                    ioctl(self._video_capture_device, VIDIOC_S_CTRL,
+                          self._ag_control)
+                except:
+                    _logger.debug('AUTOGAIN control not available')
+                    pass
+
+            if self._video_capture_device is not None:
+                self._video_capture_device.close()
+
+            self._camera.save_camera_input_to_file()
+            self._camera.stop_camera_input()
+            pixbuf = gtk.gdk.pixbuf_new_from_file_at_size(self._imagepath, w, h)
+            try:
+                array = pixbuf.get_pixels()
+            except:
+                array = None
+
+        if array is not None:
+            length = len(array) / 3
+            r, g, b, i = 0, 0, 0, 0
+            for j in range(length):
+                r += ord(array[i])
+                i += 1
+                g += ord(array[i])
+                i += 1
+                b += ord(array[i])
+                i += 1
+            if luminance_only:
+                lum = int((r * 0.3 + g * 0.6 + b * 0.1) / length)
+                self._parent.lc.update_label_value('luminance', lum)
+                return lum
+            else:
+                self._parent.lc.heap.append(int((b / length)))
+                self._parent.lc.heap.append(int((g / length)))
+                self._parent.lc.heap.append(int((r / length)))
+        else:
+            if luminance_only:
+                return -1
+            else:
+                self._parent.lc.heap.append(-1)
+                self._parent.lc.heap.append(-1)
+                self._parent.lc.heap.append(-1)
+
+
diff --git a/plugins/camera_plugin.pyc b/plugins/camera_plugin.pyc
new file mode 100644
index 0000000..a557a12
--- /dev/null
+++ b/plugins/camera_plugin.pyc
diff --git a/plugins/plugin.py b/plugins/plugin.py
new file mode 100644
index 0000000..0fe836b
--- /dev/null
+++ b/plugins/plugin.py
@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+#Copyright (c) 2011 Walter Bender
+#Copyright (c) 2011 Collabora Ltd. <http://www.collabora.co.uk/>
+
+#Permission is hereby granted, free of charge, to any person obtaining a copy
+#of this software and associated documentation files (the "Software"), to deal
+#in the Software without restriction, including without limitation the rights
+#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#copies of the Software, and to permit persons to whom the Software is
+#furnished to do so, subject to the following conditions:
+
+#The above copyright notice and this permission notice shall be included in
+#all copies or substantial portions of the Software.
+
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+#THE SOFTWARE.
+
+import gobject
+
+
+class Plugin(gobject.GObject):
+    def __init__(self):
+        gobject.GObject.__init__(self)
+
+    def setup(self):
+        """ Setup is called once, when the Turtle Window is created. """
+        raise RuntimeError("You need to define setup for your plugin.")
+
+    def start(self):
+        """ start is called when run button is pressed. """
+        raise RuntimeError("You need to define start for your plugin.")
+
+    def stop(self):
+        """ stop is called when stop button is pressed. """
+        raise RuntimeError("You need to define stop for your plugin.")
+
+    def goto_background(self):
+        """ goto_background is called when the activity is sent to the
+        background. """
+        raise RuntimeError(
+            "You need to define goto_background for your plugin.")
+
+    def return_to_foreground(self):
+        """ return_to_foreground is called when the activity returns to
+        the foreground. """
+        raise RuntimeError(
+            "You need to define return_to_foreground for your plugin.")
+
+    def quit(self):
+        """ cleanup is called when the activity is exiting. """
+        raise RuntimeError("You need to define quit for your plugin.")
diff --git a/plugins/plugin.pyc b/plugins/plugin.pyc
new file mode 100644
index 0000000..cf6e6fd
--- /dev/null
+++ b/plugins/plugin.pyc
diff --git a/plugins/rfid_plugin.py b/plugins/rfid_plugin.py
new file mode 100644
index 0000000..e0cfafc
--- /dev/null
+++ b/plugins/rfid_plugin.py
@@ -0,0 +1,161 @@
+#!/usr/bin/env python
+#Copyright (C) 2010 Emiliano Pastorino <epastorino@plan.ceibal.edu.uy>
+#Copyright (c) 2011 Walter Bender
+
+#Permission is hereby granted, free of charge, to any person obtaining a copy
+#of this software and associated documentation files (the "Software"), to deal
+#in the Software without restriction, including without limitation the rights
+#to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+#copies of the Software, and to permit persons to whom the Software is
+#furnished to do so, subject to the following conditions:
+
+#The above copyright notice and this permission notice shall be included in
+#all copies or substantial portions of the Software.
+
+#THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+#IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+#FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+#AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+#LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+#OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+#THE SOFTWARE.
+
+import os
+
+from gettext import gettext as _
+
+from rfid.rfidutils import strhex2bin, strbin2dec, find_device
+
+from plugin import Plugin
+from TurtleArt.taconstants import PALETTES, PALETTE_NAMES, BLOCK_NAMES, \
+    HELP_STRINGS, BOX_STYLE
+from TurtleArt.talogo import VALUE_BLOCKS, PLUGIN_DICTIONARY
+
+import logging
+_logger = logging.getLogger('turtleart-activity RFID plugin')
+
+HAL_SERVICE = 'org.freedesktop.Hal'
+HAL_MGR_PATH = '/org/freedesktop/Hal/Manager'
+HAL_MGR_IFACE = 'org.freedesktop.Hal.Manager'
+HAL_DEV_IFACE = 'org.freedesktop.Hal.Device'
+REGEXP_SERUSB = '\/org\/freedesktop\/Hal\/devices\/usb_device['\
+                'a-z,A-Z,0-9,_]*serial_usb_[0-9]'
+
+
+class Rfid_plugin(Plugin):
+
+    def __init__(self, parent):
+        self._parent = parent
+        self._status = False
+
+        """
+        The following code will initialize a USB RFID reader. Please note that
+        in order to make this initialization function work, it is necessary to
+        set the permission for the ttyUSB device to 0666. You can do this by
+        adding a rule to /etc/udev/rules.d
+
+        As root (using sudo or su), copy the following text into a new file in
+        /etc/udev/rules.d/94-ttyUSB-rules
+
+        KERNEL=="ttyUSB[0-9]",MODE="0666"
+
+        You only have to do this once.
+        """
+
+        self.rfid_connected = False
+        self.rfid_device = find_device()
+        self.rfid_idn = ''
+
+        if self.rfid_device is not None:
+            _logger.info("RFID device found")
+            self.rfid_connected = self.rfid_device.do_connect()
+            if self.rfid_connected:
+                self.rfid_device.connect("tag-read", self._tag_read_cb)
+                self.rfid_device.connect("disconnected", self._disconnected_cb)
+
+            loop = DBusGMainLoop()
+            bus = dbus.SystemBus(mainloop=loop)
+            hmgr_iface = dbus.Interface(bus.get_object(HAL_SERVICE,
+                HAL_MGR_PATH), HAL_MGR_IFACE)
+
+            hmgr_iface.connect_to_signal('DeviceAdded', self._device_added_cb)
+
+            self._status = True
+
+    def setup(self):
+        # set up camera-specific blocks
+        if self._status:
+            PALETTES[PALETTE_NAMES.index('sensor')].append('rfid')
+            BOX_STYLE.append('rfid')
+            BLOCK_NAMES['rfid'] = [_('RFID')]
+            HELP_STRINGS['rfid'] = _("read value from RFID device")
+            PRIMITIVES['rfid'] = 'rfid'
+            VALUE_BLOCKS.append('rfid')
+            PLUGIN_DICTIONARY['rfid'] = self.prim_read_rfid
+            self._parent.lc._def_prim('rfid', 0,
+                lambda self: PLUGIN_DICTIONARY['rfid']())
+
+
+    def start(self):
+        # This gets called by the start button
+        if self._status:
+            pass
+
+    def stop(self):
+        # This gets called by the stop button
+        if self._status:
+            pass
+
+    def goto_background(self):
+        # This gets called when your process is sent to the background
+        pass
+
+    def return_to_foreground(self):
+        # This gets called when your process returns from the background
+        pass
+
+    def quit(self):
+        # This gets called by the quit button
+        pass
+
+    def _status_report(self):
+        print 'Reporting RFID status: %s' % (str(self._status))
+        return self._status
+
+    def _device_added_cb(self, path):
+        """
+        Called from hal connection when a new device is plugged.
+        """
+        if not self.rfid_connected:
+            self.rfid_device = find_device()
+            _logger.debug("DEVICE_ADDED: %s" % self.rfid_device)
+            if self.rfid_device is not None:
+                _logger.debug("DEVICE_ADDED: RFID device is not None!")
+                self.rfid_connected = self._device.do_connect()
+            if self.rfid_connected:
+                _logger.debug("DEVICE_ADDED: Connected!")
+                self.rfid_device.connect("tag-read", self._tag_read_cb)
+                self.rfid_device.connect("disconnected", self._disconnected_cb)
+
+    def _disconnected_cb(self, device, text):
+        """
+        Called when the device is disconnected.
+        """
+        self.rfid_connected = False
+        self.rfid_device = None
+
+    def _tag_read_cb(self, device, tagid):
+        """
+        Callback for "tag-read" signal. Receives the read tag id.
+        """
+        idbin = strhex2bin(tagid)
+        self.rfid_idn = strbin2dec(idbin[26:64])
+        while self.rfid_idn.__len__() < 9:
+            self.rfid_idn = '0' + self.rfid_idn
+        print tagid, idbin, self.rfid_idn
+
+    # Block primitives used in talogo
+
+    def prim_read_rfid(self):
+        if self._status:
+            return self.rfid_idn