diff --git a/Firmware-PiicoDev-Buzzer/Firmware-PiicoDev-Buzzer.ino b/Firmware-PiicoDev-Buzzer/Firmware-PiicoDev-Buzzer.ino
index 14298a8..e79142a 100644
--- a/Firmware-PiicoDev-Buzzer/Firmware-PiicoDev-Buzzer.ino
+++ b/Firmware-PiicoDev-Buzzer/Firmware-PiicoDev-Buzzer.ino
@@ -1,12 +1,17 @@
 /*
- * PiicoDev 3x RGB LED Module Firmware
+ * PiicoDev Buzzer Module Firmware
  * Written by Michael Ruppe @ Core Electronics
  * Based off the Qwiic Button Project https://github.com/sparkfun/Qwiic_Button
- * Date: NOV 2021
- * An I2C based LED module that allows control of 3x GlowBit (WS2812) LEDs
+ * Date: FEB 2023
+ * An I2C based buzzer module that allows tone and timing control
  *
  * Feel like supporting PiicoDev? Buy a module here: https://core-electronics.com.au/catalog/product/view/sku/CE07910
  *
+ * Changes in v2.0
+ *  The new v20 hardware has a louder buzzer and does not support volume control. Volume funcitons are still provisioned here but do nothing.
+ *  Pinout has changed significantly to facilitate routing the v20 hardware.
+ *  There is also a self-test utility that checks address pins are not shorted together during PCBA
+ *
  * Changes in v1.1
  *  Default address is now not shared with other smart modules
  *  hardware address switches select from the same shared pool of addresses for smart modules
@@ -20,8 +25,8 @@
 #include <avr/sleep.h> // For sleep_mode
 #include <avr/power.h> // For powering-down peripherals such as ADC and Timers
 
-#define FIRMWARE_MAJOR 0x01
-#define FIRMWARE_MINOR 0x01
+#define FIRMWARE_MAJOR 0x02
+#define FIRMWARE_MINOR 0x00
 
 #define DEVICE_ID 0x51
 #define DEFAULT_I2C_ADDRESS 0x5C    // The default address when all switches are off
@@ -38,16 +43,14 @@ enum eepromLocations {
 uint8_t oldAddress;
 
 // Hardware Connectins
-#if defined(__AVR_ATtiny806__) || defined(__AVR_ATtiny816__) || defined(__AVR_ATtiny1606__) || defined(__AVR_ATtiny1616__)
-const uint8_t powerLedPin = PIN_PC2;
-const uint16_t buzzerPins[] = {PIN_PA3, PIN_PA1, PIN_PA2}; // In ascending order of loudness
-const uint16_t buzzerCommon = PIN_PA4; // provision for push-pull drive. Unused for now...
+#if defined(__AVR_ATtiny806__) || defined(__AVR_ATtiny816__) || defined(__AVR_ATtiny1606__) || defined(__AVR_ATtiny1616__) || defined(__AVR_ATtiny3217__)
+const uint8_t powerLedPin = PIN_PA3;
 uint16_t buzzerPin = PIN_PA2;
 
-const uint8_t addressPin1 = PIN_PA7;
-const uint8_t addressPin2 = PIN_PB5;
-const uint8_t addressPin3 = PIN_PA5;
-const uint8_t addressPin4 = PIN_PB2;
+const uint8_t addressPin1 = PIN_PA6;
+const uint8_t addressPin2 = PIN_PA7;
+const uint8_t addressPin3 = PIN_PB5;
+const uint8_t addressPin4 = PIN_PB4;
 #endif
 
 // Prototyping with Arduino Uno
@@ -94,6 +97,7 @@ struct memoryMap {
   uint16_t tone;
   uint8_t volume;
   uint8_t led;
+  uint8_t selfTestResult;
 };
 
 // Register addresses.
@@ -106,6 +110,7 @@ const memoryMap registerMap = {
   .tone = 0x05,
   .volume = 0x06,
   .led = 0x07,
+  .selfTestResult = 0x09
 };
 
 volatile memoryMap valueMap = {
@@ -116,7 +121,8 @@ volatile memoryMap valueMap = {
   .i2cAddress = DEFAULT_I2C_ADDRESS,
   .tone = 0x00,
   .volume = 0x00,
-  .led = 0x01
+  .led = 0x01,
+  .selfTestResult = 0x00
 };
 
 uint8_t currentRegisterNumber;
@@ -134,6 +140,7 @@ void setAddress(char *data);
 void setTone(char *data);
 void setVolume(char *data);
 void setPowerLed(char *data);
+void getSelfTest(char *data);
 
 functionMap functions[] = {
   {registerMap.id, idReturn},
@@ -144,6 +151,7 @@ functionMap functions[] = {
   {registerMap.tone, setTone},
   {registerMap.volume, setVolume},
   {registerMap.led, setPowerLed},
+  {registerMap.selfTestResult, getSelfTest},
 };
 
 
@@ -155,8 +163,6 @@ void setup() {
   Serial.println("Begin");
 #endif
 
-  pinMode(buzzerCommon, OUTPUT); digitalWrite(buzzerCommon, LOW);
-
   // Pull up address pins
   pinMode(addressPin1, INPUT_PULLUP);
   pinMode(addressPin2, INPUT_PULLUP);
diff --git a/Firmware-PiicoDev-Buzzer/commands.ino b/Firmware-PiicoDev-Buzzer/commands.ino
index b9d8dcd..354194e 100644
--- a/Firmware-PiicoDev-Buzzer/commands.ino
+++ b/Firmware-PiicoDev-Buzzer/commands.ino
@@ -24,18 +24,13 @@ void playTone(uint16_t frequency, uint16_t duration) {
 }
 
 void setVolume(char *data) {
-  uint8_t vol = data[0];
-  if (vol >=0 && vol < COUNT_OF(buzzerPins)) volume(uint8_t(data[0]));
+  // This function is deprecated in v2.0 firmware
+  return;
 }
 
 void volume(uint8_t vol) {
-  // Reset all buzzer pins
-  for (uint8_t i = 0; i < COUNT_OF(buzzerPins); i++) {
-    pinMode(buzzerPins[i], INPUT);
-  }
-  // Select the desired pin to use
-  buzzerPin = buzzerPins[vol];
-  pinMode(buzzerPin, OUTPUT);
+  // This function is deprecated in v2.0 firmware
+  return;
 }
 
 
@@ -89,6 +84,60 @@ void setAddress(char *data) {
 }
 
 
+void getSelfTest(char *data) {
+  runSelfTest();
+  loadArray(valueMap.selfTestResult);
+}
+
+void runSelfTest(void){
+  const bool FAIL = false;
+  const bool PASS = true;
+  bool state = PASS;
+
+  // Check for shorts between address pins
+  uint8_t numPins = 4;
+  uint16_t pins[] = {addressPin1, addressPin2, addressPin3, addressPin4};
+
+  // Set all pins as input with pullup
+  for (uint8_t i=0; i<numPins; i++){
+    pinMode(pins[i], INPUT_PULLUP);
+  }
+  // Test Address Pin 1 against all others
+  pinMode(pins[0], OUTPUT);
+  digitalWrite(pins[0], LOW);
+  if (digitalRead(pins[1]) == 0) state = FAIL;
+  if (digitalRead(pins[2]) == 0) state = FAIL;
+  if (digitalRead(pins[3]) == 0) state = FAIL;
+  pinMode(pins[0], INPUT_PULLUP);
+
+  // Test Address Pin 2 against remaining pins
+  pinMode(pins[1], OUTPUT);
+  digitalWrite(pins[1], LOW);
+  if (digitalRead(pins[2]) == 0) state = FAIL;
+  if (digitalRead(pins[3]) == 0) state = FAIL;
+  pinMode(pins[1], INPUT_PULLUP);
+
+  // Test Address Pin 3 against remaining pins
+  pinMode(pins[2], OUTPUT);
+  digitalWrite(pins[2], LOW);
+  if (digitalRead(pins[3]) == 0) state = FAIL;
+  pinMode(pins[2], INPUT_PULLUP);
+
+  // Every address pin has now been tested against every other pin
+
+  // Check LED pin is not shorted to adjacent GND pin.
+  pinMode(powerLedPin, INPUT_PULLUP); // enter test state
+  digitalRead(powerLedPin);
+  if (digitalRead(powerLedPin) == 0) state = FAIL;
+  pinMode(powerLedPin, OUTPUT);
+  digitalWrite(powerLedPin, valueMap.led); // return the LED to the desired state
+
+  valueMap.selfTestResult = state;
+}
+
+
+
+
 //Loads a long into the start of the responseBuffer
 void loadArray(unsigned long myNumber)
 {
diff --git a/PiicoDev_Buzzer.py b/PiicoDev_Buzzer.py
index 5329591..09e4103 100644
--- a/PiicoDev_Buzzer.py
+++ b/PiicoDev_Buzzer.py
@@ -9,6 +9,7 @@
 _regTone=0x05
 _regVolume=0x06
 _regLED=0x07
+_regSelfTest = 0x09
 
 class PiicoDev_Buzzer(object):        
     def tone(self, freq, dur=0):
@@ -22,10 +23,12 @@ def noTone(self):
         r=self.tone(0); return r
         
     def volume(self, vol):
-        _v = int(vol); assert _v >=0 and _v <=2,"volume must be 0, 1 or 2"
-        v = vol.to_bytes(1,'big')
+        if self.whoami[0] != 1:
+            print("Warning: Volume not implemented on this hardware revision")
+            return
+        assert vol in [0,1,2],"volume must be 0, 1 or 2"
         try:
-            self.i2c.writeto_mem(self.addr, _regVolume, v)
+            self.i2c.writeto_mem(self.addr, _regVolume, vol.to_bytes(1,'big'))
             sleep_ms(5); return 0
         except: print(i2c_err_str.format(self.addr)); return 1
 
@@ -45,8 +48,18 @@ def readFirmware(self):
         try:
             v[1]=self.i2c.readfrom_mem(self.addr, _regFirmMaj, 1)
             v[0]=self.i2c.readfrom_mem(self.addr, _regFirmMin, 1)
-            return (v[1],v[0])
+            return (int.from_bytes(v[1],'big'), int.from_bytes(v[0],'big'))
         except: return(0,0)
+    
+    @property
+    def whoami(self):
+        return self.readFirmware()
+    
+    @property
+    def self_test(self):
+        """Returns the result of the self-test"""
+        result = self.i2c.readfrom_mem(self.addr, _regSelfTest, 1)
+        return int.from_bytes(result,'big')
 
     def readStatus(self):
         sts=self.i2c.readfrom_mem(self.addr, _regStatus,1)
@@ -59,7 +72,7 @@ def readID(self):
     def pwrLED(self, x):
         try: self.i2c.writeto_mem(self.addr, _regLED, bytes([x])); return 0
         except: print(i2c_err_str.format(self.addr)); return 1
-        
+           
     def __init__(self, bus=None, freq=None, sda=None, scl=None, addr=_baseAddr, id=None, volume=2):
         self.i2c = create_unified_i2c(bus=bus, freq=freq, sda=sda, scl=scl)
         a=addr
@@ -72,7 +85,8 @@ def __init__(self, bus=None, freq=None, sda=None, scl=None, addr=_baseAddr, id=N
         except Exception as e:
             print(i2c_err_str.format(self.addr))
             raise e
-        self.volume(volume)
+        if self.whoami[0] < 2: # volume deprecated in v20 design
+            self.volume(volume)
         # TODO: Check device ID - seems to timeout on Raspberry Pi (clock stretching not implemented)
 #         try:
 #             if self.readID() != _DevID:
diff --git a/examples/melody.py b/examples/melody.py
index 1e06d9e..844e5f1 100644
--- a/examples/melody.py
+++ b/examples/melody.py
@@ -4,30 +4,31 @@
 from PiicoDev_Unified import sleep_ms
 
 # Define some note-frequency pairs
-notes = {'C4':262,
-         'Db':277,
-         'D' :294,
-         'Eb':311,
-         'E' :330,
-         'F' :349,
-         'Gb':370,
-         'G' :392,
-         'Ab':415,
-         'A' :440,
-         'Bb':466,
-         'B' :494,
-         'C5':523,
+octave = 2
+notes = {'C'  : octave * 262,
+         'Db' : octave * 277,
+         'D'  : octave * 294,
+         'Eb' : octave * 311,
+         'E'  : octave * 330,
+         'F'  : octave * 349,
+         'Gb' : octave * 370,
+         'G'  : octave * 392,
+         'Ab' : octave * 415,
+         'A'  : octave * 440,
+         'Bb' : octave * 466,
+         'B'  : octave * 494,
+         'Chi': octave * 523,
          'rest':0, # zero Hertz is the same as no tone at all
          }
 
 # define a melody - two-dimensional list of notes and note-duration (ms)
 melody = [['E',    500],
           ['D',    500],
-          ['C4',   500],
+          ['C',   500],
           ['rest', 500],
           ['E',    500],
           ['D',    500],
-          ['C4',   500],
+          ['C',   500],
           ['rest', 500],
           ['G',    500],
           ['F',    250],
diff --git a/examples/software_address.py b/examples/software_address.py
new file mode 100644
index 0000000..bd7d551
--- /dev/null
+++ b/examples/software_address.py
@@ -0,0 +1,11 @@
+# PiicoDev Buzzer example. Set a software address
+# requires all ID switches to be OFF
+
+from PiicoDev_Buzzer import PiicoDev_Buzzer
+from PiicoDev_Unified import sleep_ms
+
+buzz = PiicoDev_Buzzer()
+buzz.setI2Caddr(0x64)
+
+buzz.tone(800, 500)
+sleep_ms(500)
diff --git a/main.py b/main.py
index 46f951d..b5488f7 100644
--- a/main.py
+++ b/main.py
@@ -1,18 +1,19 @@
-# PiicoDev Buzzer example. Play tones and change the volume.
+# PiicoDev Buzzer example. Play simple tones
 
 from PiicoDev_Buzzer import PiicoDev_Buzzer
 from PiicoDev_Unified import sleep_ms
 
-buzz = PiicoDev_Buzzer(volume=2) # volume may be 0, 1 or 2 (loudest)
+buzz = PiicoDev_Buzzer()
 
+# Play tones for a set duration
 buzz.tone(800, 500) # high tone (800Hz for 500ms)
 sleep_ms(500)
 
 buzz.tone(400, 500) # low tone (400Hz for 500ms)
 sleep_ms(1500)
 
-buzz.volume(0) # low volume
 
+# Play tones and stop them manually
 buzz.tone(800) # high tone - continuous
 sleep_ms(500)
 buzz.noTone() # stop playing