Getting Started with Raspberry Pi - DCC 2013.1

1. Getting Started with Raspberry Pi Tom Paulus www.tompaulus.com @tompaulus

2. Recommended

3. Books

4. Hardware

5. Model B

6. Model A

7. Model B

8. Raspberry

9. Pi Text “Take

11. bite!” CPU Broadcom ARM11 SoC Broadcom ARM11 SoC Clock Speed Up to 1GHz ClockSpeed* Up to 1GHz ClockSpeed* Memory 256 MB 512 MB USB 1 USB Port 2 USB Ports Network None Onboard Ethernet Model

12. BModel

15. Arduino

16. UNO

20. Arduino

21. MEGA

26. Raspberry

27. Pi

29. UNO MEGA DUE Pi Model A Pi Model B Operating Voltage SRAM FLASH- Memory Clock Speed USB Host Network Audio /Video Current I/O pins Digital I/O Pins Analog Input Pins Price 5V 5V 3.3V 3.3V 3.3V 2 KB 8 KB 96 KB 265 MB 512 MB 32 KB 256 KB 512 KB up to 64 MB up to 64 MB 16 MHz 16 MHz 84 MHz 700 MHz* 700 MHz* n/a n/a 1 1 2 n/a n/a n/a n/a 10/100 wired Ethernet RJ45 n/a n/a n/a HDMI, Composite Video, TRS-audio jack HDMI, Composite Video, TRS-audio jack 40 mA 40 mA total 130 mA 2 to 16 mA 2 to 16 mA 14 (6 PWM) 54 (15 PWM) 54 (12 PWM) 17 (1 PWM) 17 (1 PWM) 6 16 12 2DAC Analog Out 0* 0* $30 $59 $50 $25 $35

30. Initial Setup

31. http://www.raspberrypi.org/downloads

32. Recommended

33. SD

34. Cards •Class

36. Minimum •2

37. GB

38. or

39. More •Major

40. Brands

41. are

42. Better!

43. Creating Your Image 1. Download and Unzip the .img from www.raspberrypi.com 2. Format the SD Card to clear all Data Windows Users: Use Win32DiskImager Mac Users: in a Terminal-- sudo diskutil unmount /dev/disk1s1 sudo dd bs=1m if=(Insert Location of .img) of=(SD Card) sync sudo diskutil eject /dev/rdisk1

45. Demo

46. GPIO

48. sudo apt-get install python-dev python-pip sudo easy_install -U distribute sudo pip install RPi.GPIO Preparing

49. Python

50. Simple

51. Blink

52. App

53. #! /usr/bin/python import time import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) #use the common numeration, #also the one found on the Adafruit Cobbler led = 25 delay = .5 GPIO.setup(led, GPIO.OUT) #Set 'led' as and Output while True: GPIO.output(led, True) #led On time.sleep(delay) #wait 'delay' seconds GPIO.output(led, False) #led off time.sleep(delay) #wait another 'delay' seconds

55. Demo

56. Analogue

57. Input

58. MCP3008 8-Channel 10-Bit ADC With SPI Interface Ra!berryPi wi ADC

59. SPI requires four signals: clock (SCLK) master output/slave input (MOSI) master input/slave output (MISO) slave select (SS) or (CS) chip-select Ra!berryPi Se#al Pe#pheral Interface Bus - SPI

60. pi@raspberrypi ~ $ cat /etc/modprobe.d/raspi-blacklist.conf # blacklist spi and i2c by default (many users don't need them) blacklist spi-bcm2708 blacklist i2c-bcm2708 Loading Kernel Modules: Edit the raspi-blacklist.conf, so that the spi module gets loaded, Reboot, and conﬁrm with lsmod that ‘spidev’ and ‘spi_bcm2708’ are now loaded and ls /dev/spi* shows two spi devices: /dev/spidev0.0 and /dev/spidev0.1 Installing Dependencies: sudo apt-get install python-dev git-core Install Python bindings for Linux SPI access through spidev: cd ~ git clone git://github.com/doceme/py-spidev cd py-spidev/ sudo python setup.py install ... which creates /usr/local/lib/python2.7/dist-packages/spidev.so SPI

61. I2C SPI

62. IN =[0000 0001][1CNL ----][---- ----] (8+channel) 4 OUT=[---- ----][---- -XXX][XXXX XXXX] (10bit) ((r[1] 3) 8) + r[2]

63. IN =[0000 0001][1CNL ----][---- ----] (8+channel) 4 OUT=[---- ----][---- -XXX][XXXX XXXX] r[0] ((r[1] 3) 8) + r[2] r = spi.xfer2( [1, (8+chnnl)4, 0] ) return ((r[1] 3) 8) + r[2]

64. #! /usr/bin/python #Written By Tom Paulus, @tompaulus, www.tompaulus.com import time import spidev import RPi.GPIO as GPIO spi = spidev.SpiDev() light_adc = 7 statusLED = 25 GPIO.setmode(GPIO.BCM) GPIO.setup(statusLED, GPIO.OUT) print Press CTRL+Z to exit def analogRead(port): Read the given ADC port and preform the necessary shifting of bits spi.open(0, 0) if (port 7) or (port 0): print 'analogRead -- Port Error, Must use a port between 0 and 7' return -1 r = spi.xfer2([1, (8 + port) 4, 0]) value = ((r[1] 3) 8) + r[2] spi.close() return value while True: GPIO.output(statusLED, True) print analogRead(light_adc) time.sleep(.125) GPIO.output(statusLED, False) time.sleep(.175)

66. Demo

67. Analogue

68. Input Part

70. I2C connects the same two signal lines to all slaves. I.e. addressing is required and all devices need a unique address SDA - Serial Data SCL - Serial Clock Ra!berryPi Inter-IC Bus - I2C

71. pi@raspberrypi ~ $ cat /etc/modprobe.d/raspi-blacklist.conf # blacklist spi and i2c by default (many users don't need them) blacklist spi-bcm2708 blacklist i2c-bcm2708 Loading Kernel Modules: - Edit the raspi-blacklist.conf, so that the i2c module gets enabled. - Add the following lines to /etc/modules i2c-dev i2c-bcm2708 Reboot, and conﬁrm ls /dev/i2c* shows /dev/i2c-0 /dev/i2c-1 Installing Dependencies: sudo apt-get install python-smbus i2c-tools With i2c devices connected, run somthing like this, to discover devices addresses. sudo i2cdetect -y 0 I2C

72. I2C SPI

73. #! /usr/bin/python #Written By Tom Paulus, @tompaulus, www.tompaulus.com import time import spidev import RPi.GPIO as GPIO from Adafruit_LEDBackpack.Adafruit_7Segment import SevenSegment import smbus GPIO.setmode(GPIO.BCM) segment = SevenSegment(address=0x70) # which port the display is spi = spidev.SpiDev() light_adc = 7 l = list() statusLED = 25 print Press CTRL+Z to exit GPIO.setup(statusLED, GPIO.OUT) def analogRead(port): Read the given ADC port and preform the necessary shifting of bits spi.open(0, 0) if (port 7) or (port 0): print 'analogRead -- Port Error, Must use a port between 0 and 7' return -1 r = spi.xfer2([1, (8 + port) 4, 0]) value = ((r[1] 3) 8) + r[2] spi.close() return value

74. def movavg(list, length, value): A function that smooths the results by averaging a list #Courtesy Wolf Paulus list.append(value) if length len(list): del list[0] sum = 0 for x in list[:]: sum += x return sum / len(list) while True: GPIO.output(statusLED, True) segment.writeInt(movavg(l, 4, analogRead(light_adc))) time.sleep(.125) GPIO.output(statusLED, False) time.sleep(.175) **This program uses a modiﬁed library**

76. Demo

77. Using

78. Outside

79. Data

80. JSON

81. JavaScript

82. Object

83. Notation??? JSON?? { firstName: John, lastName: Smith, age: 25, address: { streetAddress: 21 2nd Street, city: New York, state: NY, postalCode: 10021 }, phoneNumber: [ { type: home, number: 212 555-1234 }, { type: fax, number: 646 555-4567 } ] }

84. JSON

85. meet

86. JASON { firstName: John, lastName: Smith, age: 25, address: { streetAddress: 21 2nd Street, city: New York, state: NY, postalCode: 10021 }, phoneNumber: [ { type: home, number: 212 555-1234 }, { type: fax, number: 646 555-4567 } ] }

88. What

89. time

90. is

91. it

92. in

93. city?

94. #! /usr/bin/python #Written By Tom Paulus, @tompaulus, www.tompaulus.com import lib.requests as requests import time timeURL = 'http://json-time.appspot.com/time.json?tz=' zone = 'America/Phoenix' while True: timeJson = requests.get(timeURL + zone).json() hour = timeJson['hour'] minute = timeJson['minute'] second = timeJson['second'] dateTime = timeJson['datetime'] print str(hour) + ':' + str(minute) + ':' + str(second) print dateTime time.sleep(1)

96. Displaying

97. the

98. Data

99. News Client

100. class Scroller(): def splitString(self, s, lineLength): # s = 'The Quick Brown Fox Jumps Over The Lazy Dog' #Test String string = '' length = 0 k = 0 #Counter Variable wordLength = list() strings = list() lines = list() words = s.strip().split() for k in range(0, len(words)): #Make a list of the word lengths length = len(words[k]) wordLength.append(length) k = 0 #Reset Counter while k len(words): if len(string) + len(words[k]) + 1 lineLength: if len(string) == 0: string += words[k] else: string = string + ' ' + words[k] k += 1 else: strings.append(string) string = '' if k == len(words): strings.append(string) string = '' k = 0 #Reset Counter

101. while k len(strings): #Format for Our Display if k == len(strings) - 1: line = strings[k] lines.append(line) break else: line = strings[k] + 'n' + strings[k + 1] lines.append(line) k += 2 return lines if __name__ == '__main__': s = raw_input('Enter the string to be separatedn').replace('n', '') tools = Scroller() print tools.splitString(s, 16)

102. The Quick Brown Fox Jumps Over The Lazy Dog ['The Quick BrownnFox Jumps Over', 'The Lazy Dog']

103. class NewsAPI: def get(self,count,key): Get the homepage form HackerNews :return: JSON object url = 'http://api.usatoday.com/open/articles/topnews/news?count='+str(count)+'days=0page=0encoding=jsonapi_key='+key d = requests.get(url) JSON = d.json() return JSON while True: z = 0 if update: nJson = API.get(15, API_KEY) length = len(nJson['stories']) for x in range(0, length): articles.append(nJson['stories'][x]['title']) update = False display = tools.splitString(articles[currentTitle], 16) for y in range(0, len(display)): z += 1 Timer(y * 2, rotate, args=[display[y]]).start() time.sleep(z * 2 + 2) currentTitle = (currentTitle + 1) % len(articles)

104. Demo

105. Wea!er Client

106. while True: if update: lcd.clear() lcd.message('Please WaitnFetching Data') json = API.getLocation(locations.get(str(location) + 's'), locations.get(str(location) + 'c'), token) update = False display = 0 if display == 0: lcd.clear() high = API.high(json, units_Temp) low = API.low(json, units_Temp) windSpeed = API.windSpeed(json, units_Speed) windDir = API.winDir(json) string1 = API.Display1(high, low, windSpeed, units_Speed, windDir, language) lcd.message(string1) if display == 1: lcd.clear() rain = API.rain(json) humidity = API.humidity(json) string2 = API.Display2(rain, humidity, language) lcd.message(string2) if display == 2: lcd.clear() lcd.message('More DatanComing Soon!')

107. class WebAPI: def getLocation(self, state, city, token): d = requests.get( 'http://api.wunderground.com/api/' + str(token) + '/forecast/q/' + str(state) + '/' + str(city) +'.json') json = d.json() return json def high(self, json, units): high = str(json['forecast']['simpleforecast']['forecastday'][0]['high'][units]) return high def low(self, json, units): low = str(json['forecast']['simpleforecast']['forecastday'][0]['low'][units]) return low def windSpeed(self, json, units): windSpeed = str(json['forecast']['simpleforecast']['forecastday'][0]['avewind'][units]) return windSpeed def winDir(self, json): windDir = str(json['forecast']['simpleforecast']['forecastday'][0]['avewind']['dir']) return windDir

108. Demo

109. Summary Wow! We have learned a lot!! 1. Initial Setup of the Raspberry Pi 2. Made a little LED blink 3. Dealt with an AnalogValue and Displayed it 4.The Basics of JSON 5. Got our feet wet by ﬁnding the Time in different places 6. Used our new Knowledge to ﬁnd the Weather 7.What’s new in the News?

111. Slides: Code Used in this Talk: http://tompaulus.com/talks https://github.com/tpaulus/DCC-April13 Email: [email protected]

112. Slides: Code Used in this Talk: http://tompaulus.com/talks https://github.com/tpaulus/DCC-April13 Email: [email protected]

Getting Started with Raspberry Pi - DCC 2013.1

Recommended

More Related Content

What's hot (19)

Similar to Getting Started with Raspberry Pi - DCC 2013.1 (20)

Recently uploaded (20)

Getting Started with Raspberry Pi - DCC 2013.1