From 5848252bff1dfc7c01a410163a2ae012d3905a23 Mon Sep 17 00:00:00 2001
From: Stefan Brand <seiichiro@seiichiro0185.org>
Date: Sat, 8 Feb 2020 16:27:46 +0100
Subject: [PATCH] Added Decoder for New Binary Payload Format

---
 sensord/RFM69.py         |  2 ++
 sensord/RFM69receiver.py | 69 +++++++++++++++++++++++-----------------
 2 files changed, 42 insertions(+), 29 deletions(-)

diff --git a/sensord/RFM69.py b/sensord/RFM69.py
index 418fa7f..4ad076d 100644
--- a/sensord/RFM69.py
+++ b/sensord/RFM69.py
@@ -5,6 +5,8 @@ import spidev
 import RPi.GPIO as GPIO
 import time
 
+GPIO.setwarnings(False)
+
 class RFM69(object):
     def __init__(self, freqBand, nodeID, networkID, isRFM69HW = False, intPin = 18, rstPin = 28, spiBus = 0, spiDevice = 0):
 
diff --git a/sensord/RFM69receiver.py b/sensord/RFM69receiver.py
index 0fd29db..1b2863d 100644
--- a/sensord/RFM69receiver.py
+++ b/sensord/RFM69receiver.py
@@ -4,7 +4,7 @@ rfm69receiver - A RFM69 433MHz Receiver Using the Observer Pattern
 
 import time
 import struct
-from pprint import pprint
+from pprint import pprint, pformat
 import RFM69
 from RFM69registers import RF69_433MHZ
 
@@ -13,7 +13,7 @@ class RFM69Receiver(object):
     Multiple Observers to Process the Messages
     """
 
-    def __init__(self, nodeID, netID, encKey=None):
+    def __init__(self, nodeID, netID, encKey=None, debug=False):
         """ Initialize the Transceiver Module
 
         Arguments:
@@ -26,6 +26,7 @@ class RFM69Receiver(object):
         self.__running = False
         self.__lastsid = None
         self.__lastts = 0
+        self.__debug = debug
 
         try:
             print("Initializing RFM69 Module as Node " + str(nodeID) + " on Network " + str(netID))
@@ -42,23 +43,14 @@ class RFM69Receiver(object):
 
         print("Shutting Down RFM69 Module")
         self.__rfm.shutdown()
-    def _rawbytes(self, s):
-        """Convert a string to raw bytes without encoding"""
-        outlist = []
-        for cp in s:
-            num = ord(cp)
-            if num < 255:
-                outlist.append(struct.pack('B', num))
-            elif num < 65535:
-                outlist.append(struct.pack('>H', num))
-            else:
-                b = (num & 0xFF0000) >> 16
-                H = num & 0xFFFF
-                outlist.append(struct.pack('>bH', b, H))
-        return b''.join(outlist)
 
+    def _debug(self, message):
+        """ Print Debug Output """
+        if self.__debug:
+          print('[' + time.strftime('%H:%M:%S %d %b %Y') + '][DBG] ', end='')
+          print(message)
 
-    def _process(self, sid, data, rssi):
+    def _process(self, sid, rdata, rssi):
         """ Process received Data and Notify Registered Observers
 
         Arguments:
@@ -77,6 +69,12 @@ class RFM69Receiver(object):
         msg = {}
         msg['sid'] = sid
         msg['rssi'] = rssi
+
+        try:
+          data = rdata.decode("ascii")
+        except UnicodeDecodeError:
+          data = ""
+
         if (data.find(';') != -1 and data.find('=') != -1):
           values = data.split(";")
           for value in values:
@@ -88,13 +86,29 @@ class RFM69Receiver(object):
               else:
                   msg[vsplit[0]] = int(vsplit[1].rstrip())
         else:
-          bdata = self._rawbytes(data)
-          msg['t'] = int.from_bytes(bdata[0:3], byteorder='little', signed=True)/100
-          msg['p'] = int.from_bytes(bdata[4:7], byteorder='little', signed=True)/100
-          msg['h'] = int.from_bytes(bdata[8:11], byteorder='little', signed=True)/100
-          msg['v'] = int.from_bytes(bdata[12:15], byteorder='little', signed=True)/1000
+          self._debug("Interpreting " + str(len(rdata)) + " Bytes of Binary Data from " + str(sid) + ": " + pformat(rdata))
+          if len(rdata) == 9:
+            voltage, temp, humidity = struct.unpack('<Bll', rdata)
+            msg['v'] = voltage*20/1000
+            msg['t'] = temp/100
+            msg['h'] = humidity/100
+          elif len(rdata) == 13:
+            voltage, temp, humidity, pressure = struct.unpack('<Blll', rdata)
+            msg['v'] = voltage*20/1000
+            msg['t'] = temp/100
+            msg['h'] = humidity/100
+            msg['p'] = pressure/100
+          elif len(rdata) == 16:
+            temp, pressure, humidity, voltage = struct.unpack('<llll', rdata)
+            msg['t'] = temp/100
+            msg['p'] = pressure/100
+            msg['h'] = humidity/100
+            msg['v'] = voltage/1000
+          else:
+            self._debug("Unknown data Format, could not decode!")
 
-        for observer in self.__observers:
+        if (msg['v'] < 4 and msg['h'] <= 100):
+          for observer in self.__observers:
             observer.notify(msg)
 
     def attach_observer(self, obs):
@@ -118,16 +132,13 @@ class RFM69Receiver(object):
 
             sid = self.__rfm.SENDERID
             rssi = self.__rfm.RSSI
-
-            data = ""
-            for char in self.__rfm.DATA:
-                data += chr(char)
+            rdata = bytes(self.__rfm.DATA)
 
             if self.__rfm.ACKRequested():
                 self.__rfm.sendACK()
 
             if rssi != 0:
-                self._process(sid, data, rssi)
+                self._process(sid, rdata, rssi)
 
     def stop(self):
         """ Stop the Receiving Loop """
@@ -145,5 +156,5 @@ class LogConsole(object):
     def notify(msg):
         """ Pretty-Print the received Data """
 
-        print('[' + time.strftime('%H:%M:%S %d %b %Y') + '] Message Received: ', end='')
+        print('[' + time.strftime('%H:%M:%S %d %b %Y') + '][NFO] Message Received: ', end='')
         pprint(msg)