WALT: definition and decomposition of complex problems in terms of functional and non-functional requirements

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1 Item 5: It's Totally Random Monday, 5 October 08 :5 PM IT'S TOTALLY RANDOM EXPLORE WALT: definition and decomposition of complex problems in terms of functional and non-functional requirements WILF - Defined how each component works by identifying or describing their qualities. - Identified where and why component are connected into the GPIO - Described how the circuit works and the relationships between components. A B C The student work has the following characteristics: The student work has the following characteristics: The student work has the following characteristics: Processes and purposeful definition and decomposition of complex problems in terms of production skills functional and non-functional requirements Investigating and defining - Defined how all components works by identifying or describing their qualities. - Identified why and where all of the components are connected into the GPIO - Described how the whole circuit works, with both text and images. effective definition and decomposition of complex problems in terms of functional and non-functional requirements - Defined how most components works by identifying or describing their qualities. - Identified why and where most of the components are connected into the GPIO - Described how the circuit works, with both text and images. definition and decomposition of complex problems in terms of functional and non-functional requirements - Defined how some components works by identifying or describing their qualities. - Identified why and where some of the components are connected into the GPIO - Described how the circuit works. Difficulty: easy Estimated Effort: 70 Mins Value: 0% Components List: Arduino Board USB Cable Piezo Buzzer Physical Computing and Embedded Sytems Page

2 The Piezo Buzzer is turned on and off with HIGH and LOW. Piezos contain a very thin plate inside the housing that moves when an electrical current is applied. When alternating current is applied (such as on... off... on... off), the plate vibrates and generates sound waves. It s simple to use piezos with Arduino because they can be turned on and off just like an LED. The piezo elements are not polarized and can be connected in either direction. Pins used: GND, The Voltage passing through the Arduino board is that same as USB Type - 5V. Pins 0- are Digital and so an on (5V)or off (0V) pulse is passed through them. If you wanted to have a component that is continuously on, like a light bulb, then you need to pulse on and off very rapidly so that it appears that a steady voltage is passing out the pin. This is called Pulse Width Modulation (PWM). In this item, you will only be outputting a HIGH(5V) or on and LOW (0V) or off signal through pin. The Circuit: The code will output a 5V digital pulse through pin, which will cause the Piezo Buzzer to make a sound. INSTRUCTIONS. Plug in the Piezo Buzzer into the GND and pin. Connect the RGB LED as shown in the Fritzing (circuit) diagram above. Take a photo for your portfolio, or set up a virtual circuit in tinkercad and take a screenshot.. Answer these questions: Portfolio Task Questions for EXPLORE. Define how each of the components work? Identify each component and describe how they work with text and images.. Identify what and where components are plugged into the GPIO. Why there?. Describe How the circuit works? Tell the story. Include a picture. [ use ] Physical Computing and Embedded Sytems Page

3 DEVELOP WALT: design and evaluation of user experiences and algorithms WILF Design - interpret existing code: > Analyse to identify where input, output, processing and storage occurs in the code. > translated code into pseudocode - Plan to modify parts of the code to make it work differently or more effectively Evaluation - Recommended ways to use the technology differently. Processes and production skills Generating and designing - producing and implementing A B C The student work has the following characteristics: The student work has the following characteristics: The student work has the following characteristics: purposeful design and evaluation of user experiences and algorithms - identified where all input, output, processing and storage occurs in the code. - translated all code into pseudocode - Plan to modify several parts of the code to make it work differently - Recommended ways to use the technology differently. effective design and evaluation of user experiences and algorithms - identified where most input, output, processing and storage occurs in the code. - translated most code into pseudocode - Plan to modify some parts of the code to make it work differently - Recommended some ways to use the technology differently. design and evaluation of user experiences and algorithms - identified where some input, output, processing and storage occurs in the code. - translated some code into pseudocode - Plan to modify some parts of the code to make it work differently - Recommended a way to use the technology differently. Algorithms: Sequence, iteration Code structure, values and functions: int [Data Types] To store a value in code, we use variables. There are many kinds of values or types of data that we may want to store. Integers are your primary data-type for number storage From < pinmode() [Digital I/O] Configures the specified pin to behave either as an input or an output pinmode(pin, mode) Parameters pin: the number of the pin whose mode you wish to set mode: INPUT, OUTPUT, or INPUT_PULLUP. (see the (digital pins) page for a more complete description of the functionality.) From < delay() [Time] Pauses the program for the amount of time (in milliseconds) specified as parameter. (There are 000 milliseconds in a second.) delay(ms) Physical Computing and Embedded Sytems Page

4 Parameters ms: the number of milliseconds to pause (unsigned long) From < random() The random function generates pseudo-random numbers. random(max) random(min, max) Parameters min - lower bound of the random value, inclusive (optional) max - upper bound of the random value, exclusive Returns A random number between min and max- (long). From < tone() [Advanced I/O] Generates a square wave of the specified frequency (and 50% duty cycle) on a pin. A duration can be specified, otherwise the wave continues until a call to notone(). The pin can be connected to a piezo buzzer or other speaker to play tones. Only one tone can be generated at a time. If a tone is already playing on a different pin, the call to tone() will have no effect. If the tone is playing on the same pin, the call will set its frequency. Use of the tone() function will interfere with PWM output on pins and (on boards other than the Mega). It is not possible to generate tones lower than Hz. For technical details, see Brett Hagman s notes. tone(pin, frequency) tone(pin, frequency, duration) Parameters pin: the pin on which to generate the tone frequency: the frequency of the tone in hertz - unsigned int duration: the duration of the tone in milliseconds (optional) - unsigned long From < for [Control Structure] The for statement is used to repeat a block of statements enclosed in curly braces. An increment counter is usually used to incrementand terminate the loop. The for statement is useful for any repetitive operation, and is often used in combination with arrays to operate on collections of data/pins. for (initialization; condition; increment) { //statement(s); The initialization happens first and exactly once. Each time through the loop, the condition is tested; if it s true, the statement block, and the increment is executed, then the condition is tested again. When the condition becomes false, the loop ends. From < See Item 4 for details about the tone() function. How the for loop works Let s take a close look at what is inside the parenthesis following the for loop: void setup() { for (int thispin = ; thispin < 8; thispin++) { Let s take a close look at what is inside the parenthesis following the for loop: for (int thispin = ; thispin < 8; thispin++) There are three separate statements in the parenthesis separated by a semicolon. The first statement is initialization of thecounter variable used in the for loop, it looks like any other variable declaration and initialization you have seen: Physical Computing and Embedded Sytems Page 4

5 int thispin = ; The thispin variable is what is used in the next statement called the test: thispin < 8; This is the test condition that tells the loop to keep going or to stop. If the condition is TRUE, the code in the curly brackets of the for loop will be executed again, if the condition is FALSE, the program will stop executing the statement in the for loop and move forward in the program. When we first evaluate this test condition, the thispin variable equals and the test is < 8 We know that is less than 8, so we execute the code in the curly brackets of the for loop. But before we look at the code in the curly brackets of the for loop let s finish with the final statement in the parenthesis of the for loop: thispin++ The ++ syntax means the same thing as Add to the value of variable thispin. Since adding the number one to a value issuch a common calculation to perform, the syntax ++ was created to make it even easier. Otherwise you would write: thispin = thispin + //which is the same as thispin++ On an aside, there is also a shorthand for decrementing a variable by : thispin- - //this shorthand subtracts the value from thispin On yet another aside, you can increment and decrement by any amount using the following shorthand: thispin += 4 //the += means add 4 to the variable on the left a handy syntax shortcut thispin -=4 //the -= means subtract 4 to the variable on the left another handy syntax shortcut In most cases for loops increment by the number, just keep in mind that you can increment however you choose. Enough about incrementing! What the heck is the point already? Ok, here is the deal if the condition of the for loop is met, then code in the curly brackets is executed and the counter variable is incremented. The next time through the for loop, if the condition is still met, then the code once again is executed and the counter variable is incremented again. Eventually your counter variable will grow large enough that the condition will no longer be satisfied and the for loop will end. 4 5 for (int thispin = ; thispin < 8; thispin++) { In this example, when the thispin variable gets larger than 7, the loop will stop. What is awesome about the counter variable is that we usually use it inside the for loop to help do something. In this case, the code that gets executed is: You are familiar with the pinmode() function it sets the mode of a pin. Here the number of the pin is specified by the counter variable. So what happens? The first time through the for loop, the thispin variable is equal to. Since is less than 8 (the test condition), we go ahead and execute the code inside the curly brackets: () <<< Pin is set as OUTPUT After the for loop ends the first time, we increment thispin (thispin++) so it now holds the value. Next we check the condition again, and since is indeed less than 8, the code is executed another time: Physical Computing and Embedded Sytems Page 5

6 () <<< Pin is set as OUTPUT After the for loop ends the second time, we increment thispin as before so it now holds the value 4. We check the condition we know 4 is less than 8, and we execute the code in the curly brackets of the for loop again: (4) <<< Pin 4 is set as OUTPUT This incrementing and condition testing goes on until thispin is equal to 8, now the test condition is not met, and the for loop ends and all of our pins have their mode set. Seems a bit convoluted perhaps? Consider a for loop vs. what hard coding would require: pinmode(, OUTPUT); pinmode(, OUTPUT); pinmode(4, OUTPUT); pinmode(5, OUTPUT); pinmode(6, OUTPUT); pinmode(7, OUTPUT); You can see that the for loop saved us a lot of typing! With a for loop if you decide to add LEDs, all you have to do is change the test condition by simply changing a single number. In the hard coding version you have to add more pinmode() functions to get the same result. Efficiency rocks stay away from hard coding. From < The for loop in our code for(int i = random(, 8); i > 0; i = i - random(,5)) - i is the 'counter' variable and it is set with a random initial value between and 7 (remember, it is below the max value of8 and not including 8) - the 'run the loop' condition is to keep looping while the counter, i, is a positive number (i>0). - the counter, i, is decreased in value by taking away a number between and 4 Want to know more? USING RANDOM NUMBERS WITH ARDUINO The code (sketch) causes the piezo buzzer to let off random beeps at random times. INSTRUCTIONS. Save the sketch (code) below and then open in the Arduino IDE (File>Open..) Totally_Ran dom. Copy the code into a place where you can edit it to add comments.. Answer the following: Portfolio Task Questions for DEVELOP. Where are the Input, output, storage in the code? Feature Code. How does the code work - pseudocode a. Copy the existing code b. Place comments (//) next to each line of code in pseudocode. How will you modify the circuit and/or the code to make it do something different or more effectively? 4. How could you use this technology in another way to improve the way it works or apply it to a different situation? How to write pseudocode Accepting inputs Operation Pseudocode Programming equivalent Prompt user for surname Input surname var person = prompt("please enter your name"); Physical Computing and Embedded Sytems Page 6

7 Producing outputs Print the message Hello World console.log( Hello World ); Assigning values to variables Set the total to 0 var total = 0; Performing arithmetic set total to items times price var total = items * price; Selection and Perform alternative actions Iteration or Repeating operations. Pre-test loop also known as the WHILE loop Iteration or Repeating operations. Post-test loop eg the REPEAT/UNTIL or DO/WHILE loops Iteration or Repeating operations. Counting loop also known as the FOR loop. IF mark is greater than 49 THEN print Pass ELSE print Fail WHILE total greater than 0 subtract new purchase from total ENDWHILE REPEAT <Block> UNTIL condition FOR Index = START_VALUE to FINISH_VALUE <Block> ENDFOR if (mark > 49) { console.log( Pass ); else { console.log( Fail ); while (total > 0) { total = total - new_purchase; var i = 0; do { text += "The number is " + i; i++; while (i < 5); var i; for (i = 0; i < cars.length; i++) { text += cars[i] + "<br>"; GENERATE WALT: design and implementation of modular programs, including an object-oriented program, using algorithms and data structures involving modular functions that reflect the relationships of real-world data and data entities WILF - Code implemented Processes and production skills Generating and designing - producing and implementing A B C The student work has the following characteristics: The student work has the following characteristics: The student work has the following characteristics: purposeful design and proficient implementation of modular programs, including an object-oriented program, using algorithms and data structures involving modular functions that reflect the relationships of real-world data and data entities - All code implemented effective design and effective implementation of modular programs, including an design and implementation of modular programs, including an objectoriented program, using algorithms and data structures involving modular object-oriented program, using algorithms and data structures involving modular functions that reflect the relationships of real-world data and data entities functions that reflect the relationships of real-world data and data entities - Most code implemented - Some code implemented INSTRUCTIONS. Plug in the Piezo Buzzer into the GND and pin. Take a photo for your portfolio, or set up a virtual circuit in tinkercad and take a screenshot.. Test your board with the 'Blink' sketch. Save the sketch (code) below and then open in the Arduino IDE (File>Open..) Totally_Ran dom 4. Double-check that you have the right board (Tools>Board) and COM port (Tools>Port) selected. 5. Upload your sketch (Sketch>Upload or 6. You should hear a quiet 'ticking' sound coming from the piezo buzzer, at random intervals. Youtube Video: 7. Copy and paste the code to your portfolio. Read and translate the code into pseudocode by commenting (add \\ at the end of each line) each line of code. Eg: pinmode(, OUTPUT); // set pin as an output pin 8. Modify the code to make it work differently or more effectively. Eg. Change the delay 9. Re-upload your code 0. Take a video for your portfolio.. Answer the questions below: Portfolio Task Questions for GENERATE. Get the hardware and software working. Get your modifications working and highlight where you have altered the code. document Physical Computing and Embedded Sytems Page 7

8 . Record a very short video of your working solution. EVALUATE AND REFINE WALT: evaluation of information systems and their solutions in terms of risk, sustainability and potential for innovation and enterprise WILF - Makes judgments about ideas, works, solutions or methods in relation to risk, sustainability and potential for innovation and enterprise Processes and production skills Evaluating A B C The student work has the following characteristics: The student work has the following characteristics: The student work has the following characteristics: discerning evaluation of information systems and their solutions in terms of risk, sustainability and potential for innovation and enterprise - All sections of evaluation completed and thorough. informed evaluation of information systems and their solutions in terms of risk, sustainability and potential for innovation and enterprise - Most sections of evaluation completed and thorough. evaluation of information systems and their solutions in terms of risk, sustainability and potential for innovation and enterprise - Most sections of evaluation completed. Portfolio Task Questions for EVALUATE AND REFINE. Update your kanban and burndown chart. Write a short evaluation Evaluation Critically evaluate your completed digital solution by using the organiser below. Make sure that you use full sentences and copy and paste text into paragraphs rather than leaving it in table form. Digital solution evaluation Enterprise needs and opportunities What needs or opportunities does the solution address? Risks What risks does the digital solution pose to the user s personal security? Could the digital solution have any adverse effects on the stakeholders? Sustainability How could the digital solution impact the environment? What economic factors might influence the digital solution? Is your solution easy to use and learn? Why/Why not? Are there any social factors which could affect the solution? Innovative How is the digital solution innovative? Recommendations Recommend at least one improvement that you would like to see made to the digital solution. Want More? Want More? Physical Computing and Embedded Sytems Page 8

9 [ Parts 0k Resistor RGB LED scifi_dash candle magic8 magic8_ Physical Computing and Embedded Sytems Page 9