Fix for FLOWMON-3

config.txt

@@ -3,7 +3,7 @@
 "driverFileName":"flow-monitor.py",
 "deviceName":"flowmonitor",
 "driverId":"0140",
-"releaseVersion":"4",
+"releaseVersion":"5",
 "files": {
 	"file1":"flow-monitor.py"}
 

flow-monitor.py

@@ -57,9 +57,9 @@ class Channel(object):
 
 def scale(raw_val, raw_min, raw_max, eu_min, eu_max):
     """Scale a raw value."""
-    m = (eu_max - eu_min) / (raw_max - raw_min)
-    b = eu_max - (m * raw_max)
-    return m * raw_val + b
+    slope = (eu_max - eu_min) / (raw_max - raw_min)
+    intercept = eu_max - (slope * raw_max)
+    return slope * raw_val + intercept
 
 
 def is_today(tstamp):
@@ -81,7 +81,7 @@ class start(threading.Thread, deviceBase):
                             mqtt=mqtt, Nodes=Nodes)
 
         self.daemon = True
-        self.version = "4"
+        self.version = "5"
         self.finished = threading.Event()
         threading.Thread.start(self)
 
@@ -121,7 +121,6 @@ class start(threading.Thread, deviceBase):
 
         gal_totalizer_value = 0.0
         bbl_totalizer_value = 0.0
-        last_measured_timestamp = 0
 
         last_measured_timestamp = time.time()
         conn = sqlite3.connect('/root/python_firmware/drivers/flow-monitor.db')
@@ -167,11 +166,12 @@ class start(threading.Thread, deviceBase):
 
                 now = time.time()
                 time_diff = now - last_measured_timestamp
-                gal_flow_delta = (time_diff / 60.0) * gpm_val
-                bbl_flow_delta = (time_diff / 60.0) * (1.0 / 60.0) * (1.0 / 24.0) * bpd_val
+                if time_diff > 0:
+                    gal_flow_delta = (time_diff / 60.0) * gpm_val
+                    bbl_flow_delta = (time_diff / 60.0) * (1.0 / 60.0) * (1.0 / 24.0) * bpd_val
 
-                gal_totalizer_value += gal_flow_delta
-                bbl_totalizer_value += bbl_flow_delta
+                    gal_totalizer_value += gal_flow_delta
+                    bbl_totalizer_value += bbl_flow_delta
                 last_measured_timestamp = now
 
                 cursor.execute('UPDATE flow_data SET gal_totalizer_value=?, bbl_totalizer_value=?, last_measured_timestamp=?',