IOExpander: add I2C address change example

micropython/examples/breakout_ioexpander/set_address.py

@@ -0,0 +1,30 @@
+"""
+This example shows you how to change the I2C address of an IO Expander breakout (or any of our other Nuvoton based breakouts).
+"""
+
+from breakout_ioexpander import BreakoutIOExpander
+from pimoroni_i2c import PimoroniI2C
+from pimoroni import BREAKOUT_GARDEN_I2C_PINS  # or PICO_EXPLORER_I2C_PINS or HEADER_I2C_PINS
+
+# enter the current and desired I2C addresses here
+EXISTING_ADDRESS = 0x18
+NEW_ADDRESS = 0x20
+
+i2c = PimoroniI2C(**BREAKOUT_GARDEN_I2C_PINS)
+
+# Uncomment these lines to change the address
+# ioe = BreakoutIOExpander(i2c, address=EXISTING_ADDRESS)
+# ioe.set_address(NEW_ADDRESS)
+
+# List all the connected I2C devices so we can see the change
+print('Scanning i2c bus')
+devices = i2c.scan()
+
+if len(devices) == 0:
+    print("No i2c device !")
+
+else:
+    print('i2c devices found:',len(devices))
+
+for device in devices:
+    print("Decimal address: ",device," | Hexa address: ",hex(device))