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Added additional modules, added tag to pipeline, code snapshot from o…
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…ld version.
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@kmkingsbury
kmkingsbury committed Feb 10, 2018
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2 changes: 2 additions & 0 deletions .gitlab-ci.yml
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Expand Up @@ -22,9 +22,11 @@ linting:
- flake8 .

unittesting:
tags: pi
stage: unittesting
image: python:latest
script:
- pip3 install pyyaml
- pip3 install RPi.GPIO
- cd station-code
- python3 test_collectweather.py -v
10 changes: 9 additions & 1 deletion README.md
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Expand Up @@ -38,7 +38,15 @@ Key| Type | Description | Default
```

# Python Packages
- pip3 install pyyaml
- pip3 install pyyaml

# 3rd Party Sensor Modules:
```
git clone https://github.com/PrzemoF/bmp183.git
git clone git://gist.github.com/3151375.git
git clone https://github.com/adafruit/Adafruit_Python_DHT.git
```


# Components
- Leverages gitlab and pipelines to do tasks
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252 changes: 252 additions & 0 deletions station-code/bmp183.py
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import RPi.GPIO as GPIO
import time
import numpy


# def __del__(self):
# if Groupclass:
# Groupclass.count -= 1


class bmp183():
"""Class for Bosch BMP183 pressure and temperature sensor with SPI
interface as sold by Adafruit"""
# BMP183 registers
BMP183_REG = {
# @ Calibration data
'CAL_AC1': 0xAA,
'CAL_AC2': 0xAC,
'CAL_AC3': 0xAE,
'CAL_AC4': 0xB0,
'CAL_AC5': 0xB2,
'CAL_AC6': 0xB4,
'CAL_B1': 0xB6,
'CAL_B2': 0xB8,
'CAL_MB': 0xBA,
'CAL_MC': 0xBC,
'CAL_MD': 0xBE,

# @ Chip ID. Value fixed to 0x55.
# Useful to check if communication works
'ID': 0xD0,
'ID_VALUE': 0x55,

# @ VER Undocumented
'VER': 0xD1,

# @ SOFT_RESET Write only. If set to 0xB6,
# will perform the same sequence as power on reset.
'SOFT_RESET': 0xE0,

# @ CTRL_MEAS Controls measurements
'CTRL_MEAS': 0xF4,

# @ DATA
'DATA': 0xF6,
}

# BMP183 commands
BMP183_CMD = {
# @ Chip ID Value fixed to 0x55.
# Useful to check if communication works
'ID_VALUE': 0x55,

# SPI bit to indicate READ or WRITE operation
'READWRITE': 0x80,

# Read TEMPERATURE, Wait time 4.5 ms
'TEMP': 0x2E,
'TEMP_WAIT': 0.0045,

# Read PRESSURE
'PRESS': 0x34, # 001

# PRESSURE reading modes
# Example usage: (PRESS || (OVERSAMPLE_2 << 4)
# ultra low power, no oversampling, wait time 4.5 ms
'OVERSAMPLE_0': 0x0,
'OVERSAMPLE_0_WAIT': 0.0045,
# standard, 2 internal samples, wait time 7.5 ms
'OVERSAMPLE_1': 0x1,
'OVERSAMPLE_1_WAIT': 0.0075,
# high resolution, 4 internal samples, wait time 13.5 ms
'OVERSAMPLE_2': 0x2,
'OVERSAMPLE_2_WAIT': 0.0135,
# ultra high resolution, 8 internal samples, Wait time 25.5 ms
'OVERSAMPLE_3': 0x3,
'OVERSAMPLE_3_WAIT': 0.0255,
}

def __init__(self, sck=11, sdo=15, sdi=16, cs=13):
self.temperature = 0
self.pressure = 0
# Setup Raspberry PINS, as numbered on BOARD
self.SCK = sck # GPIO for SCK, other name SCLK
self.SDO = sdo # GPIO for SDO, other name MISO
self.SDI = sdi # GPIO for SDI, other name MOSI
self.CS = cs # GPIO for CS, other name CE

# SCK frequency 1 MHz
self.delay = 1 / 1000000.0
self.set_up_gpio()

# Check comunication / read ID
ret = self.read_byte(self.BMP183_REG['ID'])
if ret != self.BMP183_CMD['ID_VALUE']:
print("BMP183 returned ", ret, " instead of 0x55. \
Communication failed, expect problems.")

self.read_calibration_data()
# Proceed with initial pressure/temperature measurement
self.measure_pressure()

def __del__(self):
self.cleanup_gpio()

def set_up_gpio(self):
# GPIO initialisation
GPIO.setmode(GPIO.BOARD)
GPIO.setup(self.SCK, GPIO.OUT, initial=GPIO.HIGH)
GPIO.setup(self.CS, GPIO.OUT, initial=GPIO.HIGH)
GPIO.setup(self.SDI, GPIO.OUT)
GPIO.setup(self.SDO, GPIO.IN)

def cleanup_gpio(self):
# GPIO clean up
try:
GPIO.cleanup(self.SCK)
GPIO.cleanup(self.CS)
GPIO.cleanup(self.SDI)
GPIO.cleanup(self.SDO)
except Exception:
pass

def read_byte(self, addr):
# Read byte from SPI interface from address "addr"
ret_value = self.spi_transfer(addr, 0, 1, 8)
return ret_value

def read_word(self, addr, extra_bits=0):
# Read word from SPI interface from address "addr",
# option to extend read by up to 3 bits
ret_value = self.spi_transfer(addr, 0, 1, 16 + extra_bits)
return ret_value

def write_byte(self, addr, value):
# Write byte of "value" to SPI interface at address "addr"
self.spi_transfer(addr, value, 0, 8)

def spi_transfer(self, addr, value, rw, length):
# Bit banging at address "addr", "rw" indicates READ (1) or
# WRITE (1) operation
ret_value = 0
if (rw == 0):
spi_addr = addr & (~self.BMP183_CMD['READWRITE'])
else:
spi_addr = addr | self.BMP183_CMD['READWRITE']

GPIO.output(self.CS, 0)
time.sleep(self.delay)
for i in range(8):
bit = spi_addr & (0x01 << (7 - i))
if (bit):
GPIO.output(self.SDI, 1)
else:
GPIO.output(self.SDI, 0)
GPIO.output(self.SCK, 0)
time.sleep(self.delay)
GPIO.output(self.SCK, 1)
time.sleep(self.delay)

if (rw == 1):
for i in range(length):
GPIO.output(self.SCK, 0)
time.sleep(self.delay)
bit = GPIO.input(self.SDO)
GPIO.output(self.SCK, 1)
ret_value = (ret_value << 1) | bit
time.sleep(self.delay)

if (rw == 0):
for i in range(length):
bit = value & (0x01 << (length - 1 - i))
if (bit):
GPIO.output(self.SDI, 1)
else:
GPIO.output(self.SDI, 0)
GPIO.output(self.SCK, 0)
time.sleep(self.delay)
GPIO.output(self.SCK, 1)
time.sleep(self.delay)
GPIO.output(self.CS, 1)
return ret_value

def read_calibration_data(self):
# Read calibration data
self.AC1 = numpy.int16(self.read_word(self.BMP183_REG['CAL_AC1']))
self.AC2 = numpy.int16(self.read_word(self.BMP183_REG['CAL_AC2']))
self.AC3 = numpy.int16(self.read_word(self.BMP183_REG['CAL_AC3']))
self.AC4 = numpy.uint16(self.read_word(self.BMP183_REG['CAL_AC4']))
self.AC5 = numpy.uint16(self.read_word(self.BMP183_REG['CAL_AC5']))
self.AC6 = numpy.uint16(self.read_word(self.BMP183_REG['CAL_AC6']))
self.B1 = numpy.int16(self.read_word(self.BMP183_REG['CAL_B1']))
self.B2 = numpy.int16(self.read_word(self.BMP183_REG['CAL_B2']))
self.MB = numpy.int16(self.read_word(self.BMP183_REG['CAL_MB']))
self.MC = numpy.int16(self.read_word(self.BMP183_REG['CAL_MC']))
self.MD = numpy.int16(self.read_word(self.BMP183_REG['CAL_MD']))

def measure_temperature(self):
# Start temperature measurement
self.write_byte(self.BMP183_REG['CTRL_MEAS'],
self.BMP183_CMD['TEMP'])
# Wait
time.sleep(self.BMP183_CMD['TEMP_WAIT'])
# Read uncmpensated temperature
self.UT = numpy.int32(self.read_word(self.BMP183_REG['DATA']))
self.calculate_temperature()

def measure_pressure(self):
# Measure temperature - required for calculations
self.measure_temperature()
# Read 3 samples of uncompensated pressure
UP = {}
for i in range(3):
# Start pressure measurement
self.write_byte(self.BMP183_REG['CTRL_MEAS'],
self.BMP183_CMD['PRESS'] |
(self.BMP183_CMD['OVERSAMPLE_3'] << 4))
# Wait for conversion
time.sleep(self.BMP183_CMD['OVERSAMPLE_3_WAIT'])
# Store uncmpensated pressure for averaging
UP[i] = numpy.int32(self.read_word(self.BMP183_REG['DATA'], 3))

self.UP = (UP[0] + UP[1] + UP[2]) / 3
self.calculate_pressure()

def calculate_pressure(self):
# Calculate atmospheric pressure in [Pa]
self.B6 = self.B5 - 4000
X1 = (self.B2 * (self.B6 * self.B6 / 2 ** 12)) / 2 ** 11
X2 = self.AC2 * self.B6 / 2 ** 11
X3 = X1 + X2
self.B3 = (((numpy.uint32(self.AC1 * 4 + X3)) <<
self.BMP183_CMD['OVERSAMPLE_3']) + 2) / 4
X1 = self.AC3 * self.B6 / 2 ** 13
X2 = (self.B1 * (self.B6 * self.B6 / 2 ** 12)) / 2 ** 16
X3 = ((X1 + X2) + 2) / 2 ** 2
self.B4 = numpy.uint32(self.AC4 * (X3 + 32768) / 2 ** 15)
self.B7 = (numpy.uint32(self.UP) - self.B3) * (
50000 >> self.BMP183_CMD['OVERSAMPLE_3'])
p = numpy.uint32((self.B7 * 2) / self.B4)
X1 = (p / 2 ** 8) * (p / 2 ** 8)
X1 = int(X1 * 3038) / 2 ** 16
X2 = int(-7357 * p) / 2 ** 16
self.pressure = p + (X1 + X2 + 3791) / 2 ** 4

def calculate_temperature(self):
# Calculate temperature in [degC]
X1 = (self.UT - self.AC6) * self.AC5 / 2 ** 15
X2 = self.MC * 2 ** 11 / (X1 + self.MD)
self.B5 = X1 + X2
self.T = (self.B5 + 8) / 2 ** 4
self.temperature = self.T / 10.0
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