From 7300ad4ba267767492df8223f220eab6c5a1f4d8 Mon Sep 17 00:00:00 2001
From: The Weather PI <thisone@gmail.com>
Date: Wed, 12 Jul 2017 21:32:04 +0000
Subject: [PATCH] Added python code.

---
 in_python/bmp180.py | 145 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 145 insertions(+)
 create mode 100755 in_python/bmp180.py

diff --git a/in_python/bmp180.py b/in_python/bmp180.py
new file mode 100755
index 0000000..366423e
--- /dev/null
+++ b/in_python/bmp180.py
@@ -0,0 +1,145 @@
+#!/usr/bin/python
+#--------------------------------------
+#
+#           bmp180.py
+#  Read data from a digital pressure sensor.
+#  And broadcast to network.
+#  Author : Jony Silva
+#  Date   : Wed 12 Jul 21:03:26 UTC 2017
+#
+#  Reading the chip code taken from :
+#  http://www.raspberrypi-spy.co.uk/
+#
+#--------------------------------------
+import smbus
+import time
+from socket import *
+from ctypes import c_short
+ 
+DEVICE = 0x77 # Default device I2C address
+ 
+# addressing information of target
+IPADDR = '<broadcast>'
+PORTNUM = 10000
+ 
+#bus = smbus.SMBus(0)  # Rev 1 Pi uses 0
+bus = smbus.SMBus(1) # Rev 2 Pi uses 1 
+ 
+def convertToString(data):
+	# Simple function to convert binary data into
+	# a string
+	return str((data[1] + (256 * data[0])) / 1.2)
+
+def getShort(data, index):
+	# return two bytes from data as a signed 16-bit value
+	return c_short((data[index] << 8) + data[index + 1]).value
+
+def getUshort(data, index):
+	# return two bytes from data as an unsigned 16-bit value
+	return (data[index] << 8) + data[index + 1]
+
+def readBmp180Id(addr=DEVICE):
+	# Chip ID Register Address
+	REG_ID     = 0xD0
+	(chip_id, chip_version) = bus.read_i2c_block_data(addr, REG_ID, 2)
+	return (chip_id, chip_version)
+  
+def readBmp180(addr=DEVICE):
+	# Register Addresses
+	REG_CALIB  = 0xAA
+	REG_MEAS   = 0xF4
+	REG_MSB    = 0xF6
+	REG_LSB    = 0xF7
+	# Control Register Address
+	CRV_TEMP   = 0x2E
+	CRV_PRES   = 0x34 
+	# Oversample setting
+	OVERSAMPLE = 3    # 0 - 3
+
+	# Read calibration data
+	# Read calibration data from EEPROM
+	cal = bus.read_i2c_block_data(addr, REG_CALIB, 22)
+
+	# Convert byte data to word values
+	AC1 = getShort(cal, 0)
+	AC2 = getShort(cal, 2)
+	AC3 = getShort(cal, 4)
+	AC4 = getUshort(cal, 6)
+	AC5 = getUshort(cal, 8)
+	AC6 = getUshort(cal, 10)
+	B1  = getShort(cal, 12)
+	B2  = getShort(cal, 14)
+	MB  = getShort(cal, 16)
+	MC  = getShort(cal, 18)
+	MD  = getShort(cal, 20)
+
+	# Read temperature
+	bus.write_byte_data(addr, REG_MEAS, CRV_TEMP)
+	time.sleep(0.005)
+	(msb, lsb) = bus.read_i2c_block_data(addr, REG_MSB, 2)
+	UT = (msb << 8) + lsb
+
+	# Read pressure
+	bus.write_byte_data(addr, REG_MEAS, CRV_PRES + (OVERSAMPLE << 6))
+	time.sleep(0.04)
+	(msb, lsb, xsb) = bus.read_i2c_block_data(addr, REG_MSB, 3)
+	UP = ((msb << 16) + (lsb << 8) + xsb) >> (8 - OVERSAMPLE)
+
+	# Refine temperature
+	X1 = ((UT - AC6) * AC5) >> 15
+	X2 = (MC << 11) / (X1 + MD)
+	B5 = X1 + X2
+	temperature = int(B5 + 8) >> 4
+
+	# Refine pressure
+	B6  = B5 - 4000
+	B62 = int(B6 * B6) >> 12
+	X1  = (B2 * B62) >> 11
+	X2  = int(AC2 * B6) >> 11
+	X3  = X1 + X2
+	B3  = (((AC1 * 4 + X3) << OVERSAMPLE) + 2) >> 2
+
+	X1 = int(AC3 * B6) >> 13
+	X2 = (B1 * B62) >> 16
+	X3 = ((X1 + X2) + 2) >> 2
+	B4 = (AC4 * (X3 + 32768)) >> 15
+	B7 = (UP - B3) * (50000 >> OVERSAMPLE)
+
+	P = (B7 * 2) / B4
+
+	X1 = (int(P) >> 8) * (int(P) >> 8)
+	X1 = (X1 * 3038) >> 16
+	X2 = int(-7357 * P) >> 16
+	pressure = int(P + ((X1 + X2 + 3791) >> 4))
+
+	return (temperature/10.0,pressure/100.0)
+
+def main():
+    
+	(chip_id, chip_version) = readBmp180Id()
+	print("Chip ID     : {0}".format(chip_id))
+	print("Version     : {0}".format(chip_version))
+
+	print
+
+	(temperature,pressure) = readBmp180()
+	temp = "Temperature : {0} C".format(temperature)
+	press = "Pressure    : {0} mbar".format(pressure) 
+
+	print temp
+	print press
+
+	# initialize a socket, think of it as a cable
+	# SOCK_DGRAM specifies that this is UDP
+	s = socket(AF_INET, SOCK_DGRAM)
+
+	s.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
+	s.setsockopt(SOL_SOCKET, SO_BROADCAST, 1)
+	s.sendto(temp, (IPADDR, PORTNUM))
+	 
+	# close the socket
+	s.close()
+  
+if __name__=="__main__":
+   main()
+