fixed pressure unit and example

Author: ladyada

adafruit_bmp280.py

@@ -114,8 +114,8 @@ def pressure(self):
 
     @property
     def altitude(self):
-        """calculate the altitude based on the sea level pressure (seaLevelPa) - which you must enter ahead of time)"""
-        p = self.pressure / 100.0 # in Si units for Pascal
+        """calculate the altitude based on the sea level pressure (seaLevelhPa) - which you must enter ahead of time)"""
+        p = self.pressure # in Si units for hPascal
         return 44330 * (1.0 - math.pow(p / self.seaLevelhPa, 0.1903));
 
     def _read_coefficients(self):

examples/main.py

@@ -1,17 +1,21 @@
 import board
+import digitalio
 import busio
 import time
 from adafruit_bmp280 import adafruit_bmp280
 
-i2c = busio.I2C(board.SCL, board.SDA, frequency=100000)
-
-while not i2c.try_lock():    pass
-print("I2C addresses found:", [hex(i) for i in i2c.scan()])
-i2c.unlock()
-    
-# Create library object on our I2C port
+# Create library object using our Bus I2C port
+i2c = busio.I2C(board.SCL, board.SDA)
 bmp280 = adafruit_bmp280.Adafruit_BMP280_I2C(i2c)
 
+# OR create library object using our Bus SPI port
+#spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
+#bmp_cs = digitalio.DigitalInOut(board.D10)
+#bmp280 = adafruit_bmp280.Adafruit_BMP280_SPI(spi, bmp_cs)
+
+# change this to match the location's pressure (hPa) at sea level
+bmp280.seaLevelhPa = 1013.25
+
 while True:
     print("\nTemperature: %0.1f C" % bmp280.temperature)
     print("Pressure: %0.1f hPa" % bmp280.pressure)