@@ -57,16 +57,24 @@ class ina260:

     # register.

     def __init__(self, sAddr=DEFAULT_BUS_ADDRESS,

                        sbus=DEFAULT_BUS_NUMBER,

-                       config=DEFAULT_CONFIG):

+                       config=DEFAULT_CONFIG,

+                       debug=False):

         # Instantiate a smbus object.

         self.sensorAddr = sAddr

         self.bus = smbus.SMBus(sbus)

+        self.debugMode = debug

+

         # Initialize INA260 sensor.  

         initData = [(config >> 8), (config & 0x00FF)]

         self.bus.write_i2c_block_data(self.sensorAddr, CONFIG_REG, initData)

+

+        if self.debugMode:

+            data = self.getInfo()

+            print("manufacturer ID: %s %s\n"\

+                  "configuration register: %s %s\n" % data)

     ## end def

-    def status(self):

+    def getInfo(self):

         # Read manufacture identification data.

         mfcid = self.bus.read_i2c_block_data(self.sensorAddr, ID_REG, 2)

         mfcidB1 = format(mfcid[0], "08b")

@@ -91,7 +99,7 @@ class ina260:

         # Get the current data from the sensor.

         # INA260 returns the data in two bytes formatted as follows

         #        -------------------------------------------------

-        #    bit | b7  | b6  | b5  | b4  | b3  | b2  | b1  | b0  |

+        #    bit |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |

         #        -------------------------------------------------

         # byte 1 | d15 | d14 | d13 | d12 | d11 | d10 | d9  | d8  |

         #        -------------------------------------------------

@@ -100,6 +108,12 @@ class ina260:

         # The current is returned in d15-d0, a two's complement,

         # 16 bit number.  This means that d15 is the sign bit.        

         data=self.bus.read_i2c_block_data(self.sensorAddr, CUR_REG, 2)

+

+        if self.debugMode:

+            dataB1 = format(data[0], "08b")

+            dataB2 = format(data[1], "08b")

+            print("current register: %s %s" % (dataB1, dataB2))

+

         # Format into a 16 bit word.

         bdata = data[0] << 8 | data[1]

         # Convert from two's complement to integer.

@@ -126,7 +140,7 @@ class ina260:

         # Get the voltage data from the sensor.

         # INA260 returns the data in two bytes formatted as follows

         #        -------------------------------------------------

-        #    bit | b7  | b6  | b5  | b4  | b3  | b2  | b1  | b0  |

+        #    bit |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |

         #        -------------------------------------------------

         # byte 1 | d15 | d14 | d13 | d12 | d11 | d10 | d9  | d8  |

         #        -------------------------------------------------

@@ -134,6 +148,12 @@ class ina260:

         #        -------------------------------------------------

         # The voltage is returned in d15-d0 as an unsigned integer.

         data=self.bus.read_i2c_block_data(self.sensorAddr, VOLT_REG, 2)

+

+        if self.debugMode:

+            dataB1 = format(data[0], "08b")

+            dataB2 = format(data[1], "08b")

+            print("voltage register: %s %s" % (dataB1, dataB2))

+

         # Convert data to volts.

         volts = (data[0] << 8 | data[1]) * 0.00125 # LSB is 1.25 mV

         return volts

@@ -143,7 +163,7 @@ class ina260:

         # Get the wattage data from the sensor.

         # INA260 returns the data in two bytes formatted as follows

         #        -------------------------------------------------

-        #    bit | b7  | b6  | b5  | b4  | b3  | b2  | b1  | b0  |

+        #    bit | 7   |  6  |  5  |  4  |  3  |  2  |  1  |  0  |

         #        -------------------------------------------------

         # byte 1 | d15 | d14 | d13 | d12 | d11 | d10 | d9  | d8  |

         #        -------------------------------------------------

@@ -151,6 +171,12 @@ class ina260:

         #        -------------------------------------------------

         # The wattage is returned in d15-d0 as an unsigned integer.

         data=self.bus.read_i2c_block_data(self.sensorAddr, PWR_REG, 2)

+

+        if self.debugMode:

+            dataB1 = format(data[0], "08b")

+            dataB2 = format(data[1], "08b")

+            print("power register: %s %s" % (dataB1, dataB2))

+

         # Convert data to milliWatts. 

         mW = (data[0] << 8 | data[1]) * 10.0  # LSB is 10.0 mW

         return mW

@@ -159,15 +185,10 @@ class ina260:

 def test():

     # Initialize the smbus and INA260 sensor.

-    pwr1 = ina260(0x40, 1)

-    # Read the INA260 configuration register and manufacturer's ID.

-    data = pwr1.status()

-    print("manufacturer ID: %s %s\nconfiguration register: %s %s\n" % data)

+    pwr1 = ina260(0x40, 1, debug=True)

     # Print out sensor values.

     while True:

-        print("current register: %s %s" % pwr1.getCurrentReg())

         print("%6.2f mA" % pwr1.getCurrent())

-        print("volt register: %s %s" % pwr1.getVoltageReg())

         print("%6.2f V" % pwr1.getVoltage())

         print("%6.2f mW\n" % pwr1.getPower())

         time.sleep(2)

@@ -29,6 +29,8 @@

 #

 # Revision History

 #   * v10 released 01 June 2021 by J L Owrey; first release

+#   * v11 released 02 July 2021 by J L Owrey; improved sensor fault

+#     handling; improved code readability

 #

 #2345678901234567890123456789012345678901234567890123456789012345678901234567890

@@ -55,7 +57,7 @@ _PWR_SENSOR_ADDR = 0X40

 _BAT_TMP_SENSOR_ADDR = 0x48

 _AMB_TMP_SENSOR_ADDR = 0x4B

 # Set bus selector.

-_BUS_SEL = 1

+_BUS_NUMBER = 1

     ### FILE AND FOLDER LOCATIONS ###

@@ -71,9 +73,12 @@ _RRD_FILE = "/home/%s/database/powerData.rrd" % _USER

     ### GLOBAL CONSTANTS ###

 # sensor data request interval in seconds

-_DEFAULT_DATA_REQUEST_INTERVAL = 2

+_DEFAULT_SENSOR_POLLING_INTERVAL = 2

 # rrdtool database update interval in seconds

 _DATABASE_UPDATE_INTERVAL = 30

+# max number of failed attempts to get sensor data

+_MAX_FAILED_DATA_REQUESTS = 2

+

 # chart update interval in seconds

 _CHART_UPDATE_INTERVAL = 600

 # standard chart width in pixels

@@ -85,19 +90,23 @@ _AVERAGE_LINE_COLOR = '#006600'

    ### GLOBAL VARIABLES ###

-# debug output options

+# turns on or off extensive debugging messages

 debugMode = False

 verboseMode = False

 # frequency of data requests to sensors

-dataRequestInterval = _DEFAULT_DATA_REQUEST_INTERVAL

+dataRequestInterval = _DEFAULT_SENSOR_POLLING_INTERVAL

 # how often charts get updated

 chartUpdateInterval = _CHART_UPDATE_INTERVAL

+# number of failed attempts to get sensor data

+failedUpdateCount = 0

+# sensor status

+deviceOnline = False

-# Define each sensor.  This also initialzes each sensor.

-pwr = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_SEL)

-btmp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_SEL)

-atmp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_SEL)

+# Create sensor objects.  This also initialzes each sensor.

+power = ina260.ina260(_PWR_SENSOR_ADDR, _BUS_NUMBER)

+battemp = tmp102.tmp102(_BAT_TMP_SENSOR_ADDR, _BUS_NUMBER)

+ambtemp = tmp102.tmp102(_AMB_TMP_SENSOR_ADDR, _BUS_NUMBER)

   ###  PRIVATE METHODS  ###

@@ -127,21 +136,37 @@ def getEpochSeconds(sTime):

     return tSeconds

 ## end def

-def terminateAgentProcess(signal, frame):

-    """

-    Send a message to the log when the agent process gets killed

-    by the operating system.  Inform downstream clients

-    by removing output data files.

-    Parameters:

-        signal, frame - dummy parameters

-    Returns: nothing

+def setStatusToOffline():

+    """Set the detected status of the device to

+       "offline" and inform downstream clients by removing input

+       and output data files.

+       Parameters: none

+       Returns: nothing

     """

+    global deviceOnline

+

     # Inform downstream clients by removing output data file.

     if os.path.exists(_OUTPUT_DATA_FILE):

        os.remove(_OUTPUT_DATA_FILE)

-    print('%s terminating npw agent process' % getTimeStamp())

+    # If the sensor or  device was previously online, then send

+    # a message that we are now offline.

+    if deviceOnline:

+        print('%s device offline' % getTimeStamp())

+    deviceOnline = False

+##end def

+

+def terminateAgentProcess(signal, frame):

+    """Send a message to log when the agent process gets killed

+       by the operating system.  Inform downstream clients

+       by removing input and output data files.

+       Parameters:

+           signal, frame - dummy parameters

+       Returns: nothing

+    """

+    print('%s terminating agent process' % getTimeStamp())

+    setStatusToOffline()

     sys.exit(0)

-## end def

+##end def

   ###  PUBLIC METHODS  ###

@@ -156,11 +181,11 @@ def getSensorData(dData):

     dData["time"] = getTimeStamp()

     try:

-        dData["current"] = pwr.getCurrent()

-        dData["voltage"] = pwr.getVoltage()

-        dData["power"] = pwr.getPower()

-        dData["battemp"] = btmp.getTempF()

-        dData["ambtemp"] = atmp.getTempF()

+        dData["current"] = power.getCurrent()

+        dData["voltage"] = power.getVoltage()

+        dData["power"] = power.getPower()

+        dData["battemp"] = battemp.getTempF()

+        dData["ambtemp"] = ambtemp.getTempF()

     except Exception as exError:

         print("%s sensor error: %s" % (getTimeStamp(), exError))

         return False

@@ -212,6 +237,35 @@ def writeOutputFile(dData):

     return True

 ## end def

+def setStatus(updateSuccess):

+    """Detect if device is offline or not available on

+       the network. After a set number of attempts to get data

+       from the device set a flag that the device is offline.

+       Parameters:

+           updateSuccess - a boolean that is True if data request

+                           successful, False otherwise

+       Returns: nothing

+    """

+    global failedUpdateCount, deviceOnline

+

+    if updateSuccess:

+        failedUpdateCount = 0

+        # Set status and send a message to the log if the device

+        # previously offline and is now online.

+        if not deviceOnline:

+            print('%s device online' % getTimeStamp())

+            deviceOnline = True

+    else:

+        # The last attempt failed, so update the failed attempts

+        # count.

+        failedUpdateCount += 1

+

+    if failedUpdateCount >= _MAX_FAILED_DATA_REQUESTS:

+        # Max number of failed data requests, so set

+        # device status to offline.

+        setStatusToOffline()

+##end def

+

 def updateDatabase(dData):

     """

     Update the rrdtool database by executing an rrdtool system command.

@@ -439,12 +493,13 @@ def main():

     Parameters: none

     Returns: nothing

     """

-    global dataRequestInterval

-

     signal.signal(signal.SIGTERM, terminateAgentProcess)

     signal.signal(signal.SIGINT, terminateAgentProcess)

-    print('%s starting up node power agent process' % getTimeStamp())

+    # Log agent process startup time.

+    print '===================\n'\

+          '%s starting up node power agent process' % \

+                  (getTimeStamp())

     # last time output JSON file updated

     lastDataRequestTime = -1

@@ -488,6 +543,8 @@ def main():

                 ## Update the round robin database with the parsed data.

                 result = updateDatabase(dData)

+            setStatus(result)

+

         # At the chart generation interval, generate charts.

         if currentTime - lastChartUpdateTime > chartUpdateInterval:

             lastChartUpdateTime = currentTime

@@ -57,17 +57,25 @@ class tmp102:

     # register.

     def __init__(self, sAddr=DEFAULT_BUS_ADDRESS,

                  sbus=DEFAULT_BUS_NUMBER,

-                 config=DEFAULT_CONFIG): 

+                 config=DEFAULT_CONFIG,

+                 debug=False): 

         # Instantiate a smbus object

         self.sensorAddr = sAddr

         self.bus = smbus.SMBus(sbus)

+        self.debugMode = debug

+ 

         # Initialize TMP102 sensor.  

         initData = [(config >> 8), (config & 0x00FF)]

         self.bus.write_i2c_block_data(self.sensorAddr, CONFIG_REG, initData)

+

+        if self.debugMode:

+            # Read the TMP102 configuration register.

+            data = self.getInfo()

+            print("configuration register: %s %s\n" % data)

     ## end def

     # Reads the configuration register (two bytes).

-    def status(self):

+    def getInfo(self):

         # Read configuration data

         config = self.bus.read_i2c_block_data(self.sensorAddr, CONFIG_REG, 2)

         configB1 = format(config[0], "08b")

@@ -99,6 +107,12 @@ class tmp102:

         # The temperature is returned in d11-d0, a two's complement,

         # 12 bit number.  This means that d11 is the sign bit.

         data=self.bus.read_i2c_block_data(self.sensorAddr, TEMP_REG, 2)

+

+        if self.debugMode:

+            dataB1 = format(data[0], "08b")

+            dataB2 = format(data[1], "08b")

+            print("Temperature Reg: %s %s" % (dataB1, dataB2))

+

         # Format into a 12 bit word.

         bData = ( data[0] << 8 | data[1] ) >> 4

         # Convert from two's complement to integer.

@@ -121,24 +135,18 @@ class tmp102:

 def testclass():

     # Initialize the smbus and TMP102 sensor.

-    ts1 = tmp102(0x48, 1)

-    # Read the TMP102 configuration register.

-    data = ts1.status()

-    print "configuration register: %s %s\n" % data

+    ts1 = tmp102(0x48, 1, debug=True)

     # Print out sensor values.

     bAl = False

     while True:

-        regdata = ts1.getTempReg()

         tempC = ts1.getTempC()

         tempF = ts1.getTempF()

         if bAl:

             bAl = False

-            print("\033[42;30mTemperature Reg: %s %s\033[m" % regdata)

-            print("\033[42;30m%6.2f%sC  %6.2f%s                 \033[m" % \

+            print("\033[42;30m%6.2f%sC  %6.2f%sF                 \033[m" % \

                   (tempC, DEGSYM, tempF, DEGSYM))

         else:

             bAl = True

-            print("Temperature Reg: %s %s" % regdata)

             print("%6.2f%sC  %6.2f%sF" % \

                   (tempC, DEGSYM, tempF, DEGSYM))

         time.sleep(2)