moisture test

Signed-off-by: Ebbe Baß <ebbe@ping-mee.de>

SDL_Adafruit_ADS1x15/Adafruit_I2C.py

@@ -0,0 +1,161 @@
+#!/usr/bin/python
+import re
+import smbus
+
+# ===========================================================================
+# Adafruit_I2C Class
+# ===========================================================================
+
+class Adafruit_I2C(object):
+
+  @staticmethod
+  def getPiRevision():
+    "Gets the version number of the Raspberry Pi board"
+    # Revision list available at: http://elinux.org/RPi_HardwareHistory#Board_Revision_History
+    try:
+      with open('/proc/cpuinfo', 'r') as infile:
+        for line in infile:
+          # Match a line of the form "Revision : 0002" while ignoring extra
+          # info in front of the revsion (like 1000 when the Pi was over-volted).
+          match = re.match('Revision\s+:\s+.*(\w{4})$', line)
+          if match and match.group(1) in ['0000', '0002', '0003']:
+            # Return revision 1 if revision ends with 0000, 0002 or 0003.
+            return 1
+          elif match:
+            # Assume revision 2 if revision ends with any other 4 chars.
+            return 2
+        # Couldn't find the revision, assume revision 0 like older code for compatibility.
+        return 0
+    except:
+      return 0
+
+  @staticmethod
+  def getPiI2CBusNumber():
+    # Gets the I2C bus number /dev/i2c#
+    return 1 if Adafruit_I2C.getPiRevision() > 1 else 0
+
+  def __init__(self, address, busnum=-1, debug=False):
+    self.address = address
+    # By default, the correct I2C bus is auto-detected using /proc/cpuinfo
+    # Alternatively, you can hard-code the bus version below:
+    # self.bus = smbus.SMBus(0); # Force I2C0 (early 256MB Pi's)
+    # self.bus = smbus.SMBus(1); # Force I2C1 (512MB Pi's)
+    self.bus = smbus.SMBus(busnum if busnum >= 0 else Adafruit_I2C.getPiI2CBusNumber())
+    self.debug = debug
+
+  def reverseByteOrder(self, data):
+    "Reverses the byte order of an int (16-bit) or long (32-bit) value"
+    # Courtesy Vishal Sapre
+    byteCount = len(hex(data)[2:].replace('L','')[::2])
+    val       = 0
+    for i in range(byteCount):
+      val    = (val << 8) | (data & 0xff)
+      data >>= 8
+    return val
+
+  def errMsg(self):
+    print ("Error accessing 0x%02X: Check your I2C address" % self.address)
+    return -1
+
+  def write8(self, reg, value):
+    "Writes an 8-bit value to the specified register/address"
+    try:
+      self.bus.write_byte_data(self.address, reg, value)
+      if self.debug:
+        print ("I2C: Wrote 0x%02X to register 0x%02X" % (value, reg))
+    except IOError as err:
+      return self.errMsg()
+
+  def write16(self, reg, value):
+    "Writes a 16-bit value to the specified register/address pair"
+    try:
+      self.bus.write_word_data(self.address, reg, value)
+      if self.debug:
+        print ("I2C: Wrote 0x%02X to register pair 0x%02X,0x%02X" %
+         (value, reg, reg+1))
+    except IOError as err:
+      return self.errMsg()
+
+  def writeRaw8(self, value):
+    "Writes an 8-bit value on the bus"
+    try:
+      self.bus.write_byte(self.address, value)
+      if self.debug:
+        print ("I2C: Wrote 0x%02X" % value)
+    except IOError as err:
+      return self.errMsg()
+
+  def writeList(self, reg, list):
+    "Writes an array of bytes using I2C format"
+    try:
+      if self.debug:
+        print ("I2C: Writing list to register 0x%02X:" % reg)
+        print (list)
+      self.bus.write_i2c_block_data(self.address, reg, list)
+    except IOError as err:
+      return self.errMsg()
+
+  def readList(self, reg, length):
+    "Read a list of bytes from the I2C device"
+    try:
+      results = self.bus.read_i2c_block_data(self.address, reg, length)
+      if self.debug:
+        print ("I2C: Device 0x%02X returned the following from reg 0x%02X" %
+         (self.address, reg))
+        print (results)
+      return results
+    except IOError as err:
+      return self.errMsg()
+
+  def readU8(self, reg):
+    "Read an unsigned byte from the I2C device"
+    try:
+      result = self.bus.read_byte_data(self.address, reg)
+      if self.debug:
+        print ("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
+         (self.address, result & 0xFF, reg))
+      return result
+    except IOError as err:
+      return self.errMsg()
+
+  def readS8(self, reg):
+    "Reads a signed byte from the I2C device"
+    try:
+      result = self.bus.read_byte_data(self.address, reg)
+      if result > 127: result -= 256
+      if self.debug:
+        print ("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
+         (self.address, result & 0xFF, reg))
+      return result
+    except IOError as err:
+      return self.errMsg()
+
+  def readU16(self, reg, little_endian=True):
+    "Reads an unsigned 16-bit value from the I2C device"
+    try:
+      result = self.bus.read_word_data(self.address,reg)
+      # Swap bytes if using big endian because read_word_data assumes little 
+      # endian on ARM (little endian) systems.
+      if not little_endian:
+        result = ((result << 8) & 0xFF00) + (result >> 8)
+      if (self.debug):
+        print ("I2C: Device 0x%02X returned 0x%04X from reg 0x%02X" % (self.address, result & 0xFFFF, reg))
+      return result
+    except IOError as err:
+      return self.errMsg()
+
+  def readS16(self, reg, little_endian=True):
+    "Reads a signed 16-bit value from the I2C device"
+    try:
+      result = self.readU16(reg,little_endian)
+      if result > 32767: result -= 65536
+      return result
+    except IOError as err:
+      return self.errMsg()
+
+if __name__ == '__main__':
+  try:
+    bus = Adafruit_I2C(address=0)
+    print ("Default I2C bus is accessible")
+  except:
+    print ("Error accessing default I2C bus")

SDL_Adafruit_ADS1x15/SDL_Adafruit_ADS1x15.py

@@ -0,0 +1,783 @@
+#!/usr/bin/python
+
+#mods SwitchDoc Labs May 2016
+import time
+import smbus
+from Adafruit_I2C import Adafruit_I2C
+
+# ===========================================================================
+# ADS1x15 Class
+#
+# Originally written by K. Townsend, Adafruit (https://github.com/adafruit/Adafruit-Raspberry-Pi-Python-Code/tree/master/Adafruit_ADS1x15)
+# Updates and new functions implementation by Pedro Villanueva, 03/2013.
+# The only error in the original code was in line 57:
+#              __ADS1015_REG_CONFIG_DR_920SPS    = 0x0050
+# should be 
+#              __ADS1015_REG_CONFIG_DR_920SPS    = 0x0060     
+#
+# NOT IMPLEMENTED: Conversion ready pin, page 15 datasheet.
+# ===========================================================================
+
+class ADS1x15:
+  i2c = None
+
+  # IC Identifiers
+  __IC_ADS1015                      = 0x00
+  __IC_ADS1115                      = 0x01
+
+  # Pointer Register
+  __ADS1015_REG_POINTER_MASK        = 0x03
+  __ADS1015_REG_POINTER_CONVERT     = 0x00
+  __ADS1015_REG_POINTER_CONFIG      = 0x01
+  __ADS1015_REG_POINTER_LOWTHRESH   = 0x02
+  __ADS1015_REG_POINTER_HITHRESH    = 0x03
+
+  # Config Register
+  __ADS1015_REG_CONFIG_OS_MASK      = 0x8000
+  __ADS1015_REG_CONFIG_OS_SINGLE    = 0x8000  # Write: Set to start a single-conversion
+  __ADS1015_REG_CONFIG_OS_BUSY      = 0x0000  # Read: Bit = 0 when conversion is in progress
+  __ADS1015_REG_CONFIG_OS_NOTBUSY   = 0x8000  # Read: Bit = 1 when device is not performing a conversion
+
+  __ADS1015_REG_CONFIG_MUX_MASK     = 0x7000
+  __ADS1015_REG_CONFIG_MUX_DIFF_0_1 = 0x0000  # Differential P = AIN0, N = AIN1 (default)
+  __ADS1015_REG_CONFIG_MUX_DIFF_0_3 = 0x1000  # Differential P = AIN0, N = AIN3
+  __ADS1015_REG_CONFIG_MUX_DIFF_1_3 = 0x2000  # Differential P = AIN1, N = AIN3
+  __ADS1015_REG_CONFIG_MUX_DIFF_2_3 = 0x3000  # Differential P = AIN2, N = AIN3
+  __ADS1015_REG_CONFIG_MUX_SINGLE_0 = 0x4000  # Single-ended AIN0
+  __ADS1015_REG_CONFIG_MUX_SINGLE_1 = 0x5000  # Single-ended AIN1
+  __ADS1015_REG_CONFIG_MUX_SINGLE_2 = 0x6000  # Single-ended AIN2
+  __ADS1015_REG_CONFIG_MUX_SINGLE_3 = 0x7000  # Single-ended AIN3
+
+  __ADS1015_REG_CONFIG_PGA_MASK     = 0x0E00
+  __ADS1015_REG_CONFIG_PGA_6_144V   = 0x0000  # +/-6.144V range
+  __ADS1015_REG_CONFIG_PGA_4_096V   = 0x0200  # +/-4.096V range
+  __ADS1015_REG_CONFIG_PGA_2_048V   = 0x0400  # +/-2.048V range (default)
+  __ADS1015_REG_CONFIG_PGA_1_024V   = 0x0600  # +/-1.024V range
+  __ADS1015_REG_CONFIG_PGA_0_512V   = 0x0800  # +/-0.512V range
+  __ADS1015_REG_CONFIG_PGA_0_256V   = 0x0A00  # +/-0.256V range
+
+  __ADS1015_REG_CONFIG_MODE_MASK    = 0x0100
+  __ADS1015_REG_CONFIG_MODE_CONTIN  = 0x0000  # Continuous conversion mode
+  __ADS1015_REG_CONFIG_MODE_SINGLE  = 0x0100  # Power-down single-shot mode (default)
+
+  __ADS1015_REG_CONFIG_DR_MASK      = 0x00E0  
+  __ADS1015_REG_CONFIG_DR_128SPS    = 0x0000  # 128 samples per second
+  __ADS1015_REG_CONFIG_DR_250SPS    = 0x0020  # 250 samples per second
+  __ADS1015_REG_CONFIG_DR_490SPS    = 0x0040  # 490 samples per second
+  __ADS1015_REG_CONFIG_DR_920SPS    = 0x0060  # 920 samples per second
+  __ADS1015_REG_CONFIG_DR_1600SPS   = 0x0080  # 1600 samples per second (default)
+  __ADS1015_REG_CONFIG_DR_2400SPS   = 0x00A0  # 2400 samples per second
+  __ADS1015_REG_CONFIG_DR_3300SPS   = 0x00C0  # 3300 samples per second (also 0x00E0)
+
+  __ADS1115_REG_CONFIG_DR_8SPS      = 0x0000  # 8 samples per second
+  __ADS1115_REG_CONFIG_DR_16SPS     = 0x0020  # 16 samples per second
+  __ADS1115_REG_CONFIG_DR_32SPS     = 0x0040  # 32 samples per second
+  __ADS1115_REG_CONFIG_DR_64SPS     = 0x0060  # 64 samples per second
+  __ADS1115_REG_CONFIG_DR_128SPS    = 0x0080  # 128 samples per second
+  __ADS1115_REG_CONFIG_DR_250SPS    = 0x00A0  # 250 samples per second (default)
+  __ADS1115_REG_CONFIG_DR_475SPS    = 0x00C0  # 475 samples per second
+  __ADS1115_REG_CONFIG_DR_860SPS    = 0x00E0  # 860 samples per second
+
+  __ADS1015_REG_CONFIG_CMODE_MASK   = 0x0010
+  __ADS1015_REG_CONFIG_CMODE_TRAD   = 0x0000  # Traditional comparator with hysteresis (default)
+  __ADS1015_REG_CONFIG_CMODE_WINDOW = 0x0010  # Window comparator
+
+  __ADS1015_REG_CONFIG_CPOL_MASK    = 0x0008
+  __ADS1015_REG_CONFIG_CPOL_ACTVLOW = 0x0000  # ALERT/RDY pin is low when active (default)
+  __ADS1015_REG_CONFIG_CPOL_ACTVHI  = 0x0008  # ALERT/RDY pin is high when active
+
+  __ADS1015_REG_CONFIG_CLAT_MASK    = 0x0004  # Determines if ALERT/RDY pin latches once asserted
+  __ADS1015_REG_CONFIG_CLAT_NONLAT  = 0x0000  # Non-latching comparator (default)
+  __ADS1015_REG_CONFIG_CLAT_LATCH   = 0x0004  # Latching comparator
+
+  __ADS1015_REG_CONFIG_CQUE_MASK    = 0x0003
+  __ADS1015_REG_CONFIG_CQUE_1CONV   = 0x0000  # Assert ALERT/RDY after one conversions
+  __ADS1015_REG_CONFIG_CQUE_2CONV   = 0x0001  # Assert ALERT/RDY after two conversions
+  __ADS1015_REG_CONFIG_CQUE_4CONV   = 0x0002  # Assert ALERT/RDY after four conversions
+  __ADS1015_REG_CONFIG_CQUE_NONE    = 0x0003  # Disable the comparator and put ALERT/RDY in high state (default)
+  
+  
+  # Dictionaries with the sampling speed values
+  # These simplify and clean the code (avoid the abuse of if/elif/else clauses)
+  spsADS1115 = {
+    8:__ADS1115_REG_CONFIG_DR_8SPS,
+    16:__ADS1115_REG_CONFIG_DR_16SPS,
+    32:__ADS1115_REG_CONFIG_DR_32SPS,
+    64:__ADS1115_REG_CONFIG_DR_64SPS,
+    128:__ADS1115_REG_CONFIG_DR_128SPS,
+    250:__ADS1115_REG_CONFIG_DR_250SPS,
+    475:__ADS1115_REG_CONFIG_DR_475SPS,
+    860:__ADS1115_REG_CONFIG_DR_860SPS
+  }    
+  spsADS1015 = {
+    128:__ADS1015_REG_CONFIG_DR_128SPS,
+    250:__ADS1015_REG_CONFIG_DR_250SPS,
+    490:__ADS1015_REG_CONFIG_DR_490SPS,
+    920:__ADS1015_REG_CONFIG_DR_920SPS,
+    1600:__ADS1015_REG_CONFIG_DR_1600SPS,
+    2400:__ADS1015_REG_CONFIG_DR_2400SPS,
+    3300:__ADS1015_REG_CONFIG_DR_3300SPS
+  }
+  # Dictionariy with the programable gains
+  pgaADS1x15 = {
+    6144:__ADS1015_REG_CONFIG_PGA_6_144V,
+    4096:__ADS1015_REG_CONFIG_PGA_4_096V,
+    2048:__ADS1015_REG_CONFIG_PGA_2_048V,
+    1024:__ADS1015_REG_CONFIG_PGA_1_024V,
+    512:__ADS1015_REG_CONFIG_PGA_0_512V,
+    256:__ADS1015_REG_CONFIG_PGA_0_256V
+  }    
+  
+
+  # Constructor
+  def __init__(self, address=0x48, ic=__IC_ADS1015, debug=False):
+    # Depending on if you have an old or a new Raspberry Pi, you
+    # may need to change the I2C bus.  Older Pis use SMBus 0,
+    # whereas new Pis use SMBus 1.  If you see an error like:
+    # 'Error accessing 0x48: Check your I2C address '
+    # change the SMBus number in the initializer below!
+    self.i2c = Adafruit_I2C(address)
+    self.address = address
+    self.debug = debug
+    # Make sure the IC specified is valid
+    if ((ic < self.__IC_ADS1015) | (ic > self.__IC_ADS1115)):
+      if (self.debug):
+        print ("ADS1x15: Invalid IC specfied: %h" % ic)
+      return -1
+    else:
+      self.ic = ic
+        
+    # Set pga value, so that getLastConversionResult() can use it,
+    # any function that accepts a pga value must update this.
+    self.pga = 6144    
+ 
+  # SwitchDoc Labs Mod - added readRaw 
+  def readRaw(self, channel=0, pga=6144, sps=250):
+
+    # return raw AD Value 
+    # With invalid channel return -1
+    if (channel > 3):
+      if (self.debug):
+        print ("ADS1x15: Invalid channel specified: %d" % channel)
+      return -1
+    
+    # Disable comparator, Non-latching, Alert/Rdy active low
+    # traditional comparator, single-shot mode
+    config = self.__ADS1015_REG_CONFIG_CQUE_NONE    | \
+             self.__ADS1015_REG_CONFIG_CLAT_NONLAT  | \
+             self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
+             self.__ADS1015_REG_CONFIG_CMODE_TRAD   | \
+             self.__ADS1015_REG_CONFIG_MODE_SINGLE    
+
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+        print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps)
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+       print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps)
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga
+
+    # Set the channel to be converted
+    if channel == 3:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_3
+    elif channel == 2:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_2
+    elif channel == 1:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_1
+    else:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_0
+
+    # Set 'start single-conversion' bit
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+
+    # Write config register to the ADC
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
+
+    # Wait for the ADC conversion to complete
+    # The minimum delay depends on the sps: delay >= 1/sps
+    # We add 0.1ms to be sure
+    delay = 1.0/sps+0.0001
+    time.sleep(delay)
+
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    return ( (result[0] << 8) | (result[1]) )
+	
+    
+  def readADCSingleEnded(self, channel=0, pga=6144, sps=250):
+    "Gets a single-ended ADC reading from the specified channel in mV. \
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see datasheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    
+    # With invalid channel return -1
+    if (channel > 3):
+      if (self.debug):
+        print ("ADS1x15: Invalid channel specified: %d" % channel)
+      return -1
+    
+    # Disable comparator, Non-latching, Alert/Rdy active low
+    # traditional comparator, single-shot mode
+    config = self.__ADS1015_REG_CONFIG_CQUE_NONE    | \
+             self.__ADS1015_REG_CONFIG_CLAT_NONLAT  | \
+             self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
+             self.__ADS1015_REG_CONFIG_CMODE_TRAD   | \
+             self.__ADS1015_REG_CONFIG_MODE_SINGLE    
+
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+       print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+      print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga
+
+    # Set the channel to be converted
+    if channel == 3:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_3
+    elif channel == 2:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_2
+    elif channel == 1:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_1
+    else:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_0
+
+    # Set 'start single-conversion' bit
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+
+    # Write config register to the ADC
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
+
+    # Wait for the ADC conversion to complete
+    # The minimum delay depends on the sps: delay >= 1/sps
+    # We add 0.1ms to be sure
+    delay = 1.0/sps+0.0001
+    time.sleep(delay)
+
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    if (self.ic == self.__IC_ADS1015):
+    	# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
+    	return ( ((result[0] << 8) | (result[1] & 0xFF)) >> 4 )*pga/2048.0
+    else:
+	# Return a mV value for the ADS1115
+	# (Take signed values into account as well)
+        val = (result[0] << 8) | (result[1])
+        if val > 0x7FFF:
+          return (val - 0xFFFF)*pga/32768.0
+        else:
+          return ( (result[0] << 8) | (result[1]) )*pga/32768.0
+	
+
+  def readADCDifferential(self, chP=0, chN=1, pga=6144, sps=250):
+    "Gets a differential ADC reading from channels chP and chN in mV. \
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see data sheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    
+    # Disable comparator, Non-latching, Alert/Rdy active low
+    # traditional comparator, single-shot mode    
+    config = self.__ADS1015_REG_CONFIG_CQUE_NONE    | \
+             self.__ADS1015_REG_CONFIG_CLAT_NONLAT  | \
+             self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
+             self.__ADS1015_REG_CONFIG_CMODE_TRAD   | \
+             self.__ADS1015_REG_CONFIG_MODE_SINGLE  
+    
+    # Set channels
+    if ( (chP == 0) & (chN == 1) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_1
+    elif ( (chP == 0) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_3
+    elif ( (chP == 2) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_2_3
+    elif ( (chP == 1) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_1_3  
+    else:
+      if (self.debug):
+        print ("ADS1x15: Invalid channels specified: %d, %d" % (chP, chN))
+        return -1
+         
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init()) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+        print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps)
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+  
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+      print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga
+
+    # Set 'start single-conversion' bit
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+
+    # Write config register to the ADC
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
+
+    # Wait for the ADC conversion to complete
+    # The minimum delay depends on the sps: delay >= 1/sps
+    # We add 0.1ms to be sure
+    delay = 1.0/sps+0.0001
+    time.sleep(delay)
+
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    if (self.ic == self.__IC_ADS1015):
+    	# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
+    	return ( ((result[0] << 8) | (result[1] & 0xFF)) >> 4 )*pga/2048.0
+    else:
+	# Return a mV value for the ADS1115
+	# (Take signed values into account as well)
+        val = (result[0] << 8) | (result[1])
+        if val > 0x7FFF:
+          return (val - 0xFFFF)*pga/32768.0
+        else:
+          return ( (result[0] << 8) | (result[1]) )*pga/32768.0
+
+
+  def readADCDifferential01(self, pga=6144, sps=250):
+    "Gets a differential ADC reading from channels 0 and 1 in mV\
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see data sheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    return self.readADCDifferential(0, 1, pga, sps)
+   
+  
+  def readADCDifferential03(self, pga=6144, sps=250):
+    "Gets a differential ADC reading from channels 0 and 3 in mV \
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see data sheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    return self.readADCDifferential(0, 3, pga, sps)
+     
+  
+  def readADCDifferential13(self, pga=6144, sps=250):
+    "Gets a differential ADC reading from channels 1 and 3 in mV \
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see data sheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    return self.__readADCDifferential(1, 3, pga, sps)  
+
+
+  def readADCDifferential23(self, pga=6144, sps=250):
+    "Gets a differential ADC reading from channels 2 and 3 in mV \
+    The sample rate for this mode (single-shot) can be used to lower the noise \
+    (low sps) or to lower the power consumption (high sps) by duty cycling, \
+    see data sheet page 14 for more info. \
+    The pga must be given in mV, see page 13 for the supported values."
+    return self.readADCDifferential(2, 3, pga, sps)   
+  
+  
+  def startContinuousConversion(self, channel=0, pga=6144, sps=250): 
+    "Starts the continuous conversion mode and returns the first ADC reading \
+    in mV from the specified channel. \
+    The sps controls the sample rate. \
+    The pga must be given in mV, see datasheet page 13 for the supported values. \
+    Use getLastConversionResults() to read the next values and \
+    stopContinuousConversion() to stop converting."
+    
+    # Default to channel 0 with invalid channel, or return -1?
+    if (channel > 3):
+      if (self.debug):
+        print ("ADS1x15: Invalid channel specified: %d" % channel)
+      return -1
+    
+    # Disable comparator, Non-latching, Alert/Rdy active low
+    # traditional comparator, continuous mode
+    # The last flag is the only change we need, page 11 datasheet
+    config = self.__ADS1015_REG_CONFIG_CQUE_NONE    | \
+             self.__ADS1015_REG_CONFIG_CLAT_NONLAT  | \
+             self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
+             self.__ADS1015_REG_CONFIG_CMODE_TRAD   | \
+             self.__ADS1015_REG_CONFIG_MODE_CONTIN    
+
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init()) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+        print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+  
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+       print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga 
+    
+    # Set the channel to be converted
+    if channel == 3:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_3
+    elif channel == 2:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_2
+    elif channel == 1:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_1
+    else:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_0    
+  
+    # Set 'start single-conversion' bit to begin conversions
+    # No need to change this for continuous mode!
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+
+    # Write config register to the ADC
+    # Once we write the ADC will convert continously
+    # we can read the next values using getLastConversionResult
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
+
+    # Wait for the ADC conversion to complete
+    # The minimum delay depends on the sps: delay >= 1/sps
+    # We add 0.5ms to be sure
+    delay = 1.0/sps+0.0005
+    time.sleep(delay)
+  
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    if (self.ic == self.__IC_ADS1015):
+    	# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
+    	return ( ((result[0] << 8) | (result[1] & 0xFF)) >> 4 )*pga/2048.0
+    else:
+	# Return a mV value for the ADS1115
+	# (Take signed values into account as well)
+        val = (result[0] << 8) | (result[1])
+        if val > 0x7FFF:
+          return (val - 0xFFFF)*pga/32768.0
+        else:
+          return ( (result[0] << 8) | (result[1]) )*pga/32768.0  
+
+  def startContinuousDifferentialConversion(self, chP=0, chN=1, pga=6144, sps=250): 
+    "Starts the continuous differential conversion mode and returns the first ADC reading \
+    in mV as the difference from the specified channels. \
+    The sps controls the sample rate. \
+    The pga must be given in mV, see datasheet page 13 for the supported values. \
+    Use getLastConversionResults() to read the next values and \
+    stopContinuousConversion() to stop converting."
+    
+    # Disable comparator, Non-latching, Alert/Rdy active low
+    # traditional comparator, continuous mode
+    # The last flag is the only change we need, page 11 datasheet
+    config = self.__ADS1015_REG_CONFIG_CQUE_NONE    | \
+             self.__ADS1015_REG_CONFIG_CLAT_NONLAT  | \
+             self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW | \
+             self.__ADS1015_REG_CONFIG_CMODE_TRAD   | \
+             self.__ADS1015_REG_CONFIG_MODE_CONTIN    
+  
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init()) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+        print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+  
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+      print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % sps     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga 
+    
+    # Set channels
+    if ( (chP == 0) & (chN == 1) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_1
+    elif ( (chP == 0) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_3
+    elif ( (chP == 2) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_2_3
+    elif ( (chP == 1) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_1_3  
+    else:
+      if (self.debug):
+        print ("ADS1x15: Invalid channels specified: %d, %d" % (chP, chN))
+        return -1  
+    
+    # Set 'start single-conversion' bit to begin conversions
+    # No need to change this for continuous mode!
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+  
+    # Write config register to the ADC
+    # Once we write the ADC will convert continously
+    # we can read the next values using getLastConversionResult
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)
+  
+    # Wait for the ADC conversion to complete
+    # The minimum delay depends on the sps: delay >= 1/sps
+    # We add 0.5ms to be sure
+    delay = 1.0/sps+0.0005
+    time.sleep(delay)
+  
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    if (self.ic == self.__IC_ADS1015):
+	# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
+        return ( ((result[0] << 8) | (result[1] & 0xFF)) >> 4 )*pga/2048.0
+    else:
+	# Return a mV value for the ADS1115
+	# (Take signed values into account as well)
+        val = (result[0] << 8) | (result[1])
+        if val > 0x7FFF:
+          return (val - 0xFFFF)*pga/32768.0
+        else:
+          return ( (result[0] << 8) | (result[1]) )*pga/32768.0  
+
+	  
+  def stopContinuousConversion(self):
+    "Stops the ADC's conversions when in continuous mode \
+    and resets the configuration to its default value."
+    # Write the default config register to the ADC
+    # Once we write, the ADC will do a single conversion and 
+    # enter power-off mode.
+    config = 0x8583 # Page 18 datasheet.
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)    
+    return True
+
+  def getLastConversionResults(self):
+    "Returns the last ADC conversion result in mV"
+    # Read the conversion results
+    result = self.i2c.readList(self.__ADS1015_REG_POINTER_CONVERT, 2)
+    if (self.ic == self.__IC_ADS1015):
+    	# Shift right 4 bits for the 12-bit ADS1015 and convert to mV
+    	return ( ((result[0] << 8) | (result[1] & 0xFF)) >> 4 )*self.pga/2048.0
+    else:
+	# Return a mV value for the ADS1115
+	# (Take signed values into account as well)
+        val = (result[0] << 8) | (result[1])
+        if val > 0x7FFF:
+         return (val - 0xFFFF)*self.pga/32768.0
+        else:
+         return ( (result[0] << 8) | (result[1]) )*self.pga/32768.0  
+	
+	
+  def startSingleEndedComparator(self, channel, thresholdHigh, thresholdLow, \
+                                 pga=6144, sps=250, \
+                                 activeLow=True, traditionalMode=True, latching=False, \
+                                 numReadings=1):
+    "Starts the comparator mode on the specified channel, see datasheet pg. 15. \
+    In traditional mode it alerts (ALERT pin will go low)  when voltage exceeds  \
+    thresholdHigh until it falls below thresholdLow (both given in mV). \
+    In window mode (traditionalMode=False) it alerts when voltage doesn't lie\
+    between both thresholds.\
+    In latching mode the alert will continue until the conversion value is read. \
+    numReadings controls how many readings are necessary to trigger an alert: 1, 2 or 4.\
+    Use getLastConversionResults() to read the current value  (which may differ \
+    from the one that triggered the alert) and clear the alert pin in latching mode. \
+    This function starts the continuous conversion mode.  The sps controls \
+    the sample rate and the pga the gain, see datasheet page 13. "
+    
+    # With invalid channel return -1
+    if (channel > 3):
+      if (self.debug):
+        print ("ADS1x15: Invalid channel specified: %d" % channel)
+      return -1
+    
+    # Continuous mode
+    config = self.__ADS1015_REG_CONFIG_MODE_CONTIN     
+    
+    if (activeLow==False):
+      config |= self.__ADS1015_REG_CONFIG_CPOL_ACTVHI
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW
+      
+    if (traditionalMode==False):
+      config |= self.__ADS1015_REG_CONFIG_CMODE_WINDOW
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CMODE_TRAD
+      
+    if (latching==True):
+      config |= self.__ADS1015_REG_CONFIG_CLAT_LATCH
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CLAT_NONLAT
+      
+    if (numReadings==4):
+      config |= self.__ADS1015_REG_CONFIG_CQUE_4CONV
+    elif (numReadings==2):
+      config |= self.__ADS1015_REG_CONFIG_CQUE_2CONV
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CQUE_1CONV
+    
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init()) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      if ( (sps not in self.spsADS1015) & self.debug):	  
+         print ("ADS1x15: Invalid sps specified: %d, using 1600sps" % sps       )
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+         print ("ADS1x15: Invalid sps specified: %d, using 250sps" % sps     )
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+      print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % pga     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga
+    
+    # Set the channel to be converted
+    if channel == 3:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_3
+    elif channel == 2:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_2
+    elif channel == 1:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_1
+    else:
+      config |= self.__ADS1015_REG_CONFIG_MUX_SINGLE_0
+
+    # Set 'start single-conversion' bit to begin conversions
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+    
+    # Write threshold high and low registers to the ADC
+    # V_digital = (2^(n-1)-1)/pga*V_analog
+    if (self.ic == self.__IC_ADS1015):
+      thresholdHighWORD = int(thresholdHigh*(2048.0/pga))
+    else:
+      thresholdHighWORD = int(thresholdHigh*(32767.0/pga))
+    bytes = [(thresholdHighWORD >> 8) & 0xFF, thresholdHighWORD & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_HITHRESH, bytes) 
+  
+    if (self.ic == self.__IC_ADS1015):
+      thresholdLowWORD = int(thresholdLow*(2048.0/pga))
+    else:
+      thresholdLowWORD = int(thresholdLow*(32767.0/pga))    
+    bytes = [(thresholdLowWORD >> 8) & 0xFF, thresholdLowWORD & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_LOWTHRESH, bytes)     
+
+    # Write config register to the ADC
+    # Once we write the ADC will convert continously and alert when things happen,
+    # we can read the converted values using getLastConversionResult
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)    
+
+
+  def startDifferentialComparator(self, chP, chN, thresholdHigh, thresholdLow, \
+                                 pga=6144, sps=250, \
+                                 activeLow=True, traditionalMode=True, latching=False, \
+                                 numReadings=1):
+    "Starts the comparator mode on the specified channel, see datasheet pg. 15. \
+    In traditional mode it alerts (ALERT pin will go low)  when voltage exceeds  \
+    thresholdHigh until it falls below thresholdLow (both given in mV). \
+    In window mode (traditionalMode=False) it alerts when voltage doesn't lie\
+    between both thresholds.\
+    In latching mode the alert will continue until the conversion value is read. \
+    numReadings controls how many readings are necessary to trigger an alert: 1, 2 or 4.\
+    Use getLastConversionResults() to read the current value  (which may differ \
+    from the one that triggered the alert) and clear the alert pin in latching mode. \
+    This function starts the continuous conversion mode.  The sps controls \
+    the sample rate and the pga the gain, see datasheet page 13. "
+
+    # Continuous mode
+    config = self.__ADS1015_REG_CONFIG_MODE_CONTIN     
+    
+    if (activeLow==False):
+      config |= self.__ADS1015_REG_CONFIG_CPOL_ACTVHI
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CPOL_ACTVLOW
+      
+    if (traditionalMode==False):
+      config |= self.__ADS1015_REG_CONFIG_CMODE_WINDOW
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CMODE_TRAD
+      
+    if (latching==True):
+      config |= self.__ADS1015_REG_CONFIG_CLAT_LATCH
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CLAT_NONLAT
+      
+    if (numReadings==4):
+      config |= self.__ADS1015_REG_CONFIG_CQUE_4CONV
+    elif (numReadings==2):
+      config |= self.__ADS1015_REG_CONFIG_CQUE_2CONV
+    else:
+      config |= self.__ADS1015_REG_CONFIG_CQUE_1CONV
+    
+    # Set sample per seconds, defaults to 250sps
+    # If sps is in the dictionary (defined in init()) it returns the value of the constant
+    # othewise it returns the value for 250sps. This saves a lot of if/elif/else code!
+    if (self.ic == self.__IC_ADS1015):
+      if ( (sps not in self.spsADS1015) & self.debug):	  
+        print ("ADS1x15: Invalid sps specified: %d, using 1600sps" % sps       )
+      config |= self.spsADS1015.setdefault(sps, self.__ADS1015_REG_CONFIG_DR_1600SPS)
+    else:
+      if ( (sps not in self.spsADS1115) & self.debug):	  
+        print ("ADS1x15: Invalid sps specified: %d, using 250sps" % sps     )
+      config |= self.spsADS1115.setdefault(sps, self.__ADS1115_REG_CONFIG_DR_250SPS)
+
+    # Set PGA/voltage range, defaults to +-6.144V
+    if ( (pga not in self.pgaADS1x15) & self.debug):	  
+      print ("ADS1x15: Invalid pga specified: %d, using 6144mV" % pga     )
+    config |= self.pgaADS1x15.setdefault(pga, self.__ADS1015_REG_CONFIG_PGA_6_144V)
+    self.pga = pga
+    
+    # Set channels
+    if ( (chP == 0) & (chN == 1) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_1
+    elif ( (chP == 0) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_0_3
+    elif ( (chP == 2) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_2_3
+    elif ( (chP == 1) & (chN == 3) ):
+      config |= self.__ADS1015_REG_CONFIG_MUX_DIFF_1_3  
+    else:
+      if (self.debug):
+        print ("ADS1x15: Invalid channels specified: %d, %d" % (chP, chN))
+        return -1
+
+    # Set 'start single-conversion' bit to begin conversions
+    config |= self.__ADS1015_REG_CONFIG_OS_SINGLE
+    
+    # Write threshold high and low registers to the ADC
+    # V_digital = (2^(n-1)-1)/pga*V_analog
+    if (self.ic == self.__IC_ADS1015):
+      thresholdHighWORD = int(thresholdHigh*(2048.0/pga))
+    else:
+      thresholdHighWORD = int(thresholdHigh*(32767.0/pga))
+    bytes = [(thresholdHighWORD >> 8) & 0xFF, thresholdHighWORD & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_HITHRESH, bytes) 
+  
+    if (self.ic == self.__IC_ADS1015):
+      thresholdLowWORD = int(thresholdLow*(2048.0/pga))
+    else:
+      thresholdLowWORD = int(thresholdLow*(32767.0/pga))    
+    bytes = [(thresholdLowWORD >> 8) & 0xFF, thresholdLowWORD & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_LOWTHRESH, bytes)     
+
+    # Write config register to the ADC
+    # Once we write the ADC will convert continously and alert when things happen,
+    # we can read the converted values using getLastConversionResult
+    bytes = [(config >> 8) & 0xFF, config & 0xFF]
+    self.i2c.writeList(self.__ADS1015_REG_POINTER_CONFIG, bytes)    
+

SDL_Adafruit_ADS1x15/ads1x15_ex_comparator.py

@@ -0,0 +1,30 @@
+#!/usr/bin/python
+
+import time, signal, sys
+from Adafruit_ADS1x15 import ADS1x15
+
+def signal_handler(signal, frame):
+        print ('You pressed Ctrl+C!')
+        print (adc.getLastConversionResults()/1000.0)
+        adc.stopContinuousConversion()
+        sys.exit(0)
+
+signal.signal(signal.SIGINT, signal_handler)
+# Print 'Press Ctrl+C to exit'
+
+ADS1015 = 0x00	# 12-bit ADC
+ADS1115 = 0x01	# 16-bit ADC
+
+# Initialise the ADC using the default mode (use default I2C address)
+# Set this to ADS1015 or ADS1115 depending on the ADC you are using!
+adc = ADS1x15(ic=ADS1115)
+
+# start comparator on channel 2 with a thresholdHigh=200mV and low=100mV
+# in traditional mode, non-latching, +/-1.024V and 250sps
+adc.startSingleEndedComparator(2, 200, 100, pga=1024, sps=250, activeLow=True, traditionalMode=True, latching=False, numReadings=1)
+
+while True:
+		print (adc.getLastConversionResults()/1000.0)
+		time.sleep(0.25)
+
+#time.sleep(0.1)

SDL_Adafruit_ADS1x15/ads1x15_ex_differential.py

@@ -0,0 +1,27 @@
+#!/usr/bin/python
+
+import time, signal, sys
+from Adafruit_ADS1x15 import ADS1x15
+
+def signal_handler(signal, frame):
+        #print 'You pressed Ctrl+C!'
+        sys.exit(0)
+signal.signal(signal.SIGINT, signal_handler)
+#print 'Press Ctrl+C to exit'
+
+ADS1015 = 0x00	# 12-bit ADC
+ADS1115 = 0x01	# 16-bit ADC
+
+# Initialise the ADC using the default mode (use default I2C address)
+# Set this to ADS1015 or ADS1115 depending on the ADC you are using!
+adc = ADS1x15(ic=ADS1115)
+
+# Read channels 2 and 3 in single-ended mode, at +/-4.096V and 250sps
+volts2 = adc.readADCSingleEnded(2, 4096, 250)/1000.0
+volts3 = adc.readADCSingleEnded(3, 4096, 250)/1000.0
+
+# Now do a differential reading of channels 2 and 3
+voltsdiff = adc.readADCDifferential23(4096, 250)/1000.0
+
+# Display the two different reading for comparison purposes
+print ("%.8f %.8f %.8f %.8f" % (volts2, volts3, volts3-volts2, -voltsdiff))

SDL_Adafruit_ADS1x15/ads1x15_ex_singleended.py

@@ -0,0 +1,46 @@
+#!/usr/bin/python
+
+import time, signal, sys
+from Adafruit_ADS1x15 import ADS1x15
+
+def signal_handler(signal, frame):
+        print ('You pressed Ctrl+C!')
+        sys.exit(0)
+signal.signal(signal.SIGINT, signal_handler)
+#print 'Press Ctrl+C to exit'
+
+ADS1015 = 0x00  # 12-bit ADC
+ADS1115 = 0x01	# 16-bit ADC
+
+# Select the gain
+# gain = 6144  # +/- 6.144V
+gain = 4096  # +/- 4.096V
+# gain = 2048  # +/- 2.048V
+# gain = 1024  # +/- 1.024V
+# gain = 512   # +/- 0.512V
+# gain = 256   # +/- 0.256V
+
+# Select the sample rate
+# sps = 8    # 8 samples per second
+# sps = 16   # 16 samples per second
+# sps = 32   # 32 samples per second
+# sps = 64   # 64 samples per second
+# sps = 128  # 128 samples per second
+sps = 250  # 250 samples per second
+# sps = 475  # 475 samples per second
+# sps = 860  # 860 samples per second
+
+# Initialise the ADC using the default mode (use default I2C address)
+# Set this to ADS1015 or ADS1115 depending on the ADC you are using!
+adc = ADS1x15(ic=ADS1115)
+while (1):
+
+	# Read channel 1 in single-ended mode using the settings above
+
+	volts = adc.readADCSingleEnded(1, gain, sps) / 1000
+
+	# To read channel 3 in single-ended mode, +/- 1.024V, 860 sps use:
+	# volts = adc.readADCSingleEnded(3, 1024, 860)
+
+	print ("%.6f" % (volts))
+	time.sleep(0.5)

test.py

@@ -1,49 +1,55 @@
-import RPi.GPIO as GPIO
 import time
+import signal
+import sys
 
-GPIO.setmode(GPIO.BCM)
+sys.path.append('./SDL_Adafruit_ADS1x15')
 
-GPIO_TRIGGER = 18
-GPIO_ECHO = 24
+import SDL_Adafruit_ADS1x15 
 
-GPIO.setup(GPIO_TRIGGER, GPIO.OUT)
-GPIO.setup(GPIO_ECHO, GPIO.IN)
+def signal_handler(signal, frame):
+        print( 'You pressed Ctrl+C!')
+        sys.exit(0)
+signal.signal(signal.SIGINT, signal_handler)
 
-def distanz():
-    # setze Trigger auf HIGH
-    GPIO.output(GPIO_TRIGGER, True)
- 
-    # setze Trigger nach 0.01ms aus LOW
-    time.sleep(0.00001)
-    GPIO.output(GPIO_TRIGGER, False)
- 
-    StartZeit = time.time()
-    StopZeit = time.time()
- 
-    # speichere Startzeit
-    while GPIO.input(GPIO_ECHO) == 0:
-        StartZeit = time.time()
- 
-    # speichere Ankunftszeit
-    while GPIO.input(GPIO_ECHO) == 1:
-        StopZeit = time.time()
- 
-    # Zeit Differenz zwischen Start und Ankunft
-    TimeElapsed = StopZeit - StartZeit
-    # mit der Schallgeschwindigkeit (34300 cm/s) multiplizieren
-    # und durch 2 teilen, da hin und zurueck
-    distanz = (TimeElapsed * 34300) / 2
- 
-    return distanz
- 
-if __name__ == '__main__':
-    try:
-        while True:
-            abstand = distanz()
-            print ("Gemessene Entfernung = %.1f cm" % abstand)
-            time.sleep(1)
- 
-        # Beim Abbruch durch STRG+C resetten
-    except KeyboardInterrupt:
-        print("Messung vom User gestoppt")
-        GPIO.cleanup()
+ADS1115 = 0x01	# 16-bit ADC
+
+# Select the gain
+# gain = 6144  # +/- 6.144V
+gain = 4096  # +/- 4.096V
+# gain = 2048  # +/- 2.048V
+# gain = 1024  # +/- 1.024V
+# gain = 512   # +/- 0.512V
+# gain = 256   # +/- 0.256V
+
+# Select the sample rate
+# sps = 8    # 8 samples per second
+# sps = 16   # 16 samples per second
+# sps = 32   # 32 samples per second
+# sps = 64   # 64 samples per second
+# sps = 128  # 128 samples per second
+sps = 250  # 250 samples per second
+# sps = 475  # 475 samples per second
+# sps = 860  # 860 samples per second
+
+# Initialise the ADC using the default mode (use default I2C address)
+adc = SDL_Adafruit_ADS1x15.ADS1x15(ic=ADS1115)
+while (1):
+
+	# Read channels  in single-ended mode using the settings above
+
+	print ("--------------------")
+	voltsCh0 = adc.readADCSingleEnded(0, gain, sps) / 1000
+	rawCh0 = adc.readRaw(0, gain, sps) 
+	print ("Channel 0 =%.6fV raw=0x%4X dec=%d" % (voltsCh0, rawCh0, rawCh0))
+	voltsCh1 = adc.readADCSingleEnded(1, gain, sps) / 1000
+	rawCh1 = adc.readRaw(1, gain, sps) 
+	print ("Channel 1 =%.6fV raw=0x%4X dec=%d" % (voltsCh1, rawCh1, rawCh1))
+	voltsCh2 = adc.readADCSingleEnded(2, gain, sps) / 1000
+	rawCh2 = adc.readRaw(2, gain, sps) 
+	print ("Channel 2 =%.6fV raw=0x%4X dec=%d" % (voltsCh2, rawCh2, rawCh2))
+	voltsCh3 = adc.readADCSingleEnded(3, gain, sps) / 1000
+	rawCh3 = adc.readRaw(3, gain, sps) 
+	print ("Channel 3 =%.6fV raw=0x%4X dec=%d" % (voltsCh3, rawCh3, rawCh3))
+	print ("--------------------")
+
+	time.sleep(0.5)