{"id":83,"date":"2018-01-18T05:32:09","date_gmt":"2018-01-17T22:32:09","guid":{"rendered":"http:\/\/class.ajarnsunny.com\/?page_id=83"},"modified":"2018-02-07T16:47:43","modified_gmt":"2018-02-07T09:47:43","slug":"introduction-to-the-raspberry-pi-computer-and-gpios","status":"publish","type":"page","link":"http:\/\/class.ajarnsunny.com\/?page_id=83","title":{"rendered":"Introduction to the Raspberry Pi Computer and GPIOs"},"content":{"rendered":"
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Example 1.1<\/strong><\/span><\/p>\n

Make the following connections (see picture<\/a>):
Connect PIN 25 (GROUND)<\/strong> of the Raspberry Pi to the GND<\/strong> of the experiment board.
Connect PIN 22<\/strong> of the Raspberry Pi to LED 0 of the Lower Monitor on the experiment board.<\/p>\n

Then, run the following program (file Example1_1<\/a>):<\/p>\n

import RPi.GPIO as GPIO # Import library for GPIO (pin) access
GPIO.setmode(GPIO.BOARD) # Specify that we use the BOARD numbers (pin numbers 1-40 on the connector)
GPIO.setwarnings(False) # Disable the warning “This channel is already in use”<\/p>\n

# ******** PIN CONFIGURATION *************************************
GPIO.setup(22, GPIO.OUT) # Configure pin 22 as an output (OUT)
# ****************************************************************<\/p>\n

GPIO.output(22, 1) # Send a logic 1 to pin 22, i.e. turn on the LED connected to pin 22<\/p>\n

The program turns on<\/strong> LED 0 as you can see in this picture<\/a>.<\/p>\n

Assignment 1.A<\/strong><\/span>
After running Example 1.1, LED 0 is turned on. Now modify the program so that it turns off LED 0.<\/p>\n

Assignment 1.B<\/strong><\/span>
Add the following connection (see picture<\/a>):
Connect PIN 24 of the Raspberry Pi to LED 1 of the Lower Monitor on the experiment board.
Modify the program of the previous assignment so that it turns on LED 0 and also LED 1 as in this picture<\/a>.<\/p>\n

Assignment 1.C<\/strong><\/span>
After running the program of assignment 1.B, LED 0 and LED1 are turned on. Modify the program so that it turns off LED 0 and LED 1.<\/p><\/div>\n\n <\/div>\n \t\t<\/div>\n\t\t\n\t\t\n\t\t\n <\/div>\n \n <\/div>\n \n\t\t\t\n\t\t\n\t\t\t

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Example 1.2<\/strong><\/span>
The following program (file Example1.2<\/a>) is a modification of example 1.1. The program makes the LED blink for three times, using time intervals of 0.5 seconds (see video<\/a>).
import time # Import the time library
import RPi.GPIO as GPIO # Import library for GPIO (pin) access
GPIO.setmode(GPIO.BOARD) # Specify that we use the BOARD numbers (pin numbers 1-40 on the connector)
GPIO.setwarnings(False) # Disable the warning “This channel is already in use”<\/p>\n

# ******** PIN CONFIGURATION *************************************
GPIO.setup(22, GPIO.OUT) # Configure pin 22 as an output (OUT)
# ****************************************************************<\/p>\n

GPIO.output(22, 1) # Send a logic 1 to pin 22, i.e. turn on the LED
time.sleep(0.5) # The program “waits” here for 0.5s
GPIO.output(22, 0) # Send a logic 0 to pin 22, i.e. turn off the LED
time.sleep(0.5) # The program “waits” here for 0.5s
GPIO.output(22, 1)
time.sleep(0.5)
GPIO.output(22, 0)
time.sleep(0.5)
GPIO.output(22, 1)
time.sleep(0.5)
GPIO.output(22, 0)<\/p><\/div>\n\n\n\n\n

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Assignment 1.D<\/strong><\/span>
Modify assignment 1.B. The two LEDs should blink three times as in this video<\/a>. Use time intervals of 0.5 seconds.<\/p>\n

Assignment 1.E<\/strong><\/span>
Modify assignment 1.D. Now the two LEDs should blink three times but with a slightly different pattern as shown in this video<\/a>. Use time intervals of 0.5 seconds.<\/p>\n

Assignment 1.F<\/strong><\/span>
Add the following connection (see picture<\/a>):
Connect PIN 26 of the Raspberry Pi to LED 2 of the Lower Monitor on the experiment board.
Write a program that “makes the light move” right-left-right as in this video<\/a>.<\/p><\/div>\n\n <\/div>\n \t\t<\/div>\n\t\t\n\t\t\n\t\t\n <\/div>\n \n <\/div>\n \n\t\t\t\n\t\t\n\t\t\t

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Look at the section<\/strong><\/span>\u00a0For and While Loops in Python<\/a>\u00a0and then continue with the next assignments.<\/span><\/strong><\/p><\/div>\n\n <\/div>\n \t\t<\/div>\n\t\t\n\t\t\n\t\t\n <\/div>\n \n <\/div>\n \n\t\t\t\n\t\t\n\t\t\t

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Assignment 1.G<\/strong><\/span>
Modify example 1.2. Use an infinite loop to make LED 0<\/strong> blink indefinitely (i.e. forever). Then, stop the program using CTRL+C.<\/p>\n

Assignment 1.H<\/strong><\/span>
Modify assignment 1.D. Use an infinite loop to make the two LEDs blink indefinitely. Hint:<\/p><\/div>\n\n\n\n \n

\n\n \n
\n \"hint_as1_H\" \n <\/div>\n \n \n \n <\/div>\n \n\n\n\n\n
\n \n

\u00a0<\/p>\n

Assignment 1.I<\/strong><\/span>
Modify assignment 1.E. Use an infinite loop to make the two LEDs blink indefinitely.<\/p><\/div>\n\n\n\n \n

\n\n \n
\n \"hint_as1_I\" \n <\/div>\n \n \n \n <\/div>\n \n\n\n\n\n
\n \n

\u00a0<\/p>\n

Assignment 1.J<\/strong><\/span>
Modify assignment 1.F. Use an infinite loop to make the light “move” right-left-right-left indefinitely. Hint:<\/p><\/div>\n\n\n\n \n

\n\n \n
\n \"hint_as1_J\" \n <\/div>\n \n \n \n <\/div>\n \n\n\n\n\n
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\u00a0<\/p>\n

Assignment 1.K<\/strong><\/span>
Modify assignment 1.J. The three LEDs should blink indefinitely with a pattern as in this video<\/a>.<\/p>\n

Assignment 1.L<\/strong><\/span>
Modify assignment 1.K. The three LEDs should blink indefinitely with a pattern as in this video<\/a>.<\/p><\/div>\n\n <\/div>\n \t\t<\/div>\n\t\t\n\t\t\n\t\t\n <\/div>\n \n <\/div>\n \n\t\t\t\n\t\t\n\t\t\t

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Seven Segment Display<\/strong><\/span><\/p>\n

Connect PIN 25 (GROUND)<\/strong> of the Raspberry Pi to the GND<\/strong> of the experiment board. Then make the following connections between the Raspberry Pi pins and the 7-segment display socket (see picture<\/a>):
Connect PIN 23 to a<\/span><\/strong>
Connect PIN 21 to b<\/span><\/strong>
Connect PIN 19 to c<\/span><\/strong>
Connect PIN 15 to d<\/span><\/strong>
Connect PIN 13 to e<\/span><\/strong>
Connect PIN 11 to f<\/span><\/strong>
Connect PIN 7 to g<\/span><\/strong>
You must also connect the common cathode of one of the three 7-segment displays (<\/strong>for instance DIGIT1) <\/strong>to GND.<\/strong><\/span><\/p>\n

The 7-segment display socket pins a, b, c,…,g, are connected to the 7 LEDs inside the display according to the following scheme:<\/p>\n


Assignment 1.M<\/strong><\/span>
Write a program (see video<\/a>) that displays the sequence 0, 1, 2 on the display and then turns off the display (i.e. all the LEDs should be off after the program terminates). Use time intervals of 1s.
Hints:
1. Configure the seven pins 23, 21, 19, 15, 13, 11, 7 as outputs.
2. Then, use a sequence of seven output functions for each of the rows in the table below to make the numbers 0, 1, 2 appear on the display. Obviously you have to complete the table first.<\/p>\n

<\/p>\n

Assignment 1.N<\/strong><\/span>
Modify the previous assignment. This time the program should displays the sequence 0, 1, 2 indefinitely as shown in this video<\/a>.<\/p><\/div>\n\n <\/div>\n \t\t<\/div>\n\t\t\n\t\t\n\t\t\n <\/div>\n \n <\/div>\n \n\t\t<\/div>\n","protected":false},"excerpt":{"rendered":"

Example 1.1 Make the following connections (see picture): Connect PIN 25 (GROUND) of the Raspberry Pi to the GND of the experiment board. Connect PIN 22 of the Raspberry Pi to LED 0 of the Lower Monitor on the experiment board. Then, run the following program (file Example1_1): import RPi.GPIO as GPIO # Import library […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":14,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-83","page","type-page","status-publish","hentry","has-post-title","has-post-date","has-post-category","has-post-tag","has-post-comment","has-post-author",""],"_links":{"self":[{"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/pages\/83"}],"collection":[{"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=83"}],"version-history":[{"count":15,"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/pages\/83\/revisions"}],"predecessor-version":[{"id":224,"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/pages\/83\/revisions\/224"}],"up":[{"embeddable":true,"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=\/wp\/v2\/pages\/14"}],"wp:attachment":[{"href":"http:\/\/class.ajarnsunny.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=83"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}