diff --git a/kdoorpi/kdoorpi/wiegand.py b/kdoorpi/kdoorpi/wiegand.py
new file mode 100644
index 0000000..519299b
--- /dev/null
+++ b/kdoorpi/kdoorpi/wiegand.py
@@ -0,0 +1,165 @@
+#!/bin/python
+import logging
+from smartcard.util import toHexString
+#import settings
+
+try:
+    import pigpio
+except Exception:
+    pigpio = False
+
+class Decoder:
+    """
+   A class to read Wiegand codes of an arbitrary length.
+   """
+
+    def __init__(self, callback, bit_timeout=5):
+
+        """
+        Instantiate with the pi, gpio for 0 (green wire), the gpio for 1
+        (white wire), the callback function, and the bit timeout in
+        milliseconds which indicates the end of a code.
+
+        The callback is passed the code length in bits and the hex value.
+        """
+        if pigpio:
+            self.pi = pigpio.pi()
+        else:
+            self.pi = False
+
+        self.gpio_0 = 17 #settings.WIEGAND[0]
+        self.gpio_1 = 18 #settings.WIEGAND[1]
+
+        self.callback = callback
+
+        self.bit_timeout = bit_timeout
+        self.items = []
+        self.in_code = False
+
+        if self.pi:
+            self.pi.set_mode(self.gpio_0, pigpio.INPUT)
+            self.pi.set_mode(self.gpio_1, pigpio.INPUT)
+
+            self.pi.set_pull_up_down(self.gpio_0, pigpio.PUD_UP)
+            self.pi.set_pull_up_down(self.gpio_1, pigpio.PUD_UP)
+
+            self.cb_0 = self.pi.callback(self.gpio_0, pigpio.FALLING_EDGE, self._cb)
+            self.cb_1 = self.pi.callback(self.gpio_1, pigpio.FALLING_EDGE, self._cb)
+
+    def cut_empty(self, item):
+        if item[0:8] == "00000000":
+            return self.cut_empty(item[8:])
+        else:
+            return item
+
+
+    def get_hex(self):
+        try:
+            items = self.items
+            if len(self.items) == 26:
+                items = self.items[1:-1]
+            elif len(self.items) == 64:
+                items = self.cut_empty(self.items)
+
+            bits = []
+            for i in range(len(items), 0, -8):
+                bits.append(int(items[i - 8:i], 2))
+            return toHexString(bits)
+
+        except ValueError:
+            logging.error("Wiegand convert error: bin to hex convertion ended with ValeError. raw: " + str(self.items))
+            return False
+
+        except Exception as e:
+            logging.error("Wiegand convert error: (raw: " + str(self.items) + ") "  + str(e))
+            return False
+
+    def _cb(self, gpio_pin, level, tick):
+
+        """
+        Accumulate bits until both gpios 0 and 1 timeout.
+        """
+
+        try:
+            if level < pigpio.TIMEOUT:
+
+                if self.in_code:
+                    self.bits += 1
+                else:
+                    logging.debug("Wiegand data transfer start")
+                    self.bits = 1
+                    self.items = ""
+                    self.in_code = True
+                    self.code_timeout = 0
+                    self.pi.set_watchdog(self.gpio_0, self.bit_timeout)
+                    self.pi.set_watchdog(self.gpio_1, self.bit_timeout)
+
+                if gpio_pin == self.gpio_0:
+                    self.code_timeout &= 2  # clear gpio 0 timeout
+                    self.items += "1"
+                else:
+                    self.code_timeout &= 1  # clear gpio 1 timeout
+                    self.items += "0"
+
+            else:
+
+                if self.in_code:
+
+                    if gpio_pin == self.gpio_0:
+                        self.code_timeout |= 1  # timeout gpio 0
+                    else:
+                        self.code_timeout |= 2  # timeout gpio 1
+
+                    if self.code_timeout == 3:  # both gpios timed out
+                        self.pi.set_watchdog(self.gpio_0, 0)
+                        self.pi.set_watchdog(self.gpio_1, 0)
+                        self.in_code = False
+
+                        if self.bits >= 26:
+                            hex = self.get_hex()
+                            if hex:
+                                self.callback(self.bits, hex)
+                        else:
+                            logging.error("Wiegand receive error: Expected at least 26 got %i bits. raw: %s" %(self.bits, self.items))
+
+        except Exception as e:
+            logging.error("Wiegand callback error: " + str(e))
+
+    def cancel(self):
+
+        """
+        Cancel the Wiegand decoder.
+        """
+
+        self.cb_0.cancel()
+        self.cb_1.cancel()
+        self.pi.stop()
+
+
+
+
+if __name__ == "__main__":
+    from urllib.request import urlopen
+    import json
+
+    print("downloading users list")
+    r = urlopen("http://127.0.0.1:8080/api/v1/cards")
+    users = json.loads(r.read().decode())["keycards"]
+    cards = {}
+    for user in users:
+        cards[user["card_uid"].strip()] = user
+
+    def wiegand_callback(bits, value):
+        print("bits", bits)
+        print("value", value)
+        print("user", cards.get(value))
+
+    logging.basicConfig(level=logging.DEBUG)
+
+    print("Running")
+    w = Decoder(wiegand_callback)
+    from time import sleep
+    while 1:
+        sleep(1)
+
+