3.1.13 GAME– 10 Second

Introduction

Next, follow me to make a game device to challenge your concentration. Tie the tilt switch to a stick to make a magic wand. Shake the wand, the 4-digit segment display will start counting, shake again will let it stop counting. If you succeed in keeping the displayed count at 10.00, then you win. You can play the game with your friends to see who is the time wizard.

Components

_images/list_GAME_10_Second.png

Schematic Diagram

T-Board Name

physical

wiringPi

BCM

GPIO17

Pin 11

0

17

GPIO27

Pin 13

2

27

GPIO22

Pin 15

3

22

SPIMOSI

Pin 19

12

10

GPIO18

Pin 12

1

18

GPIO23

Pin 16

4

23

GPIO24

Pin 18

5

24

GPIO26

Pin 37

25

26

_images/Schematic_three_one13.png

Experimental Procedures

Step 1: Build the circuit.

10 second_bb

For C Language Users

Step 2: Go to the folder of the code.

cd /home/pi/davinci-kit-for-raspberry-pi/c/3.1.13/

Step 3: Compile the code.

gcc 3.1.13_GAME_10Second.c -lwiringPi

Step 4: Run the executable file.

sudo ./a.out

Shake the wand, the 4-digit segment display will start counting, shake again will let it stop counting. If you succeed in keeping the displayed count at 10.00, then you win. Shake it one more time to start the next round of the game.

Note

If it does not work after running, or there is an error prompt: “wiringPi.h: No such file or directory”, please refer to C code is not working?.

Code Explanation

void stateChange(){
    if (gameState == 0){
        counter = 0;
        delay(1000);
        ualarm(10000,10000);
    }else{
        alarm(0);
        delay(1000);
    }
    gameState = (gameState + 1)%2;
}

The game is divided into two modes:

gameState=0 is the “start” mode, in which the time is timed and displayed on the segment display, and the tilting switch is shaken to enter the “show” mode.

GameState =1 is the “show” mode, which stops the timing and displays the time on the segment display. Shaking the tilt switch again will reset the timer and restart the game.

void loop(){
    int currentState =0;
    int lastState=0;
    while(1){
        display();
        currentState=digitalRead(sensorPin);
        if((currentState==0)&&(lastState==1)){
            stateChange();
        }
        lastState=currentState;
    }
}

Loop() is the main function. First, the time is displayed on the 4-bit segment display and the value of the tilt switch is read. If the state of the tilt switch has changed, stateChange() is called.

For Python Language Users

Step 2: Go to the folder of the code.

cd /home/pi/davinci-kit-for-raspberry-pi/python/

Step 3: Run the executable file.

sudo python3 3.1.13_GAME_10Second.py

Shake the wand, the 4-digit segment display will start counting, shake again will let it stop counting. If you succeed in keeping the displayed count at 10.00, then you win. Shake it one more time to start the next round of the game.

Code

Note

You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path like davinci-kit-for-raspberry-pi/python.

import RPi.GPIO as GPIO
import time
import threading

sensorPin = 26

SDI = 24
RCLK = 23
SRCLK = 18

placePin = (10, 22, 27, 17)
number = (0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92, 0x82, 0xf8, 0x80, 0x90)

counter = 0
timer =0
gameState =0

def clearDisplay():
    for i in range(8):
        GPIO.output(SDI, 1)
        GPIO.output(SRCLK, GPIO.HIGH)
        GPIO.output(SRCLK, GPIO.LOW)
    GPIO.output(RCLK, GPIO.HIGH)
    GPIO.output(RCLK, GPIO.LOW)

def hc595_shift(data):
    for i in range(8):
        GPIO.output(SDI, 0x80 & (data << i))
        GPIO.output(SRCLK, GPIO.HIGH)
        GPIO.output(SRCLK, GPIO.LOW)
    GPIO.output(RCLK, GPIO.HIGH)
    GPIO.output(RCLK, GPIO.LOW)

def pickDigit(digit):
    for i in placePin:
        GPIO.output(i,GPIO.LOW)
    GPIO.output(placePin[digit], GPIO.HIGH)

def display():
    global counter
    clearDisplay()
    pickDigit(0)
    hc595_shift(number[counter % 10])

    clearDisplay()
    pickDigit(1)
    hc595_shift(number[counter % 100//10])

    clearDisplay()
    pickDigit(2)
    hc595_shift(number[counter % 1000//100]-0x80)

    clearDisplay()
    pickDigit(3)
    hc595_shift(number[counter % 10000//1000])

def stateChange():
    global gameState
    global counter
    global timer1
    if gameState == 0:
        counter = 0
        time.sleep(1)
        timer()
    elif gameState ==1:
        timer1.cancel()
        time.sleep(1)
    gameState = (gameState+1)%2

def loop():
    global counter
    currentState = 0
    lastState = 0
    while True:
        display()
        currentState=GPIO.input(sensorPin)
        if (currentState == 0) and (lastState == 1):
            stateChange()
        lastState=currentState

def timer():
    global counter
    global timer1
    timer1 = threading.Timer(0.01, timer)
    timer1.start()
    counter += 1

def setup():
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(SDI, GPIO.OUT)
    GPIO.setup(RCLK, GPIO.OUT)
    GPIO.setup(SRCLK, GPIO.OUT)
    for i in placePin:
        GPIO.setup(i, GPIO.OUT)
    GPIO.setup(sensorPin, GPIO.IN)

def destroy():   # When \"Ctrl+C\" is pressed, the function is executed.
    GPIO.cleanup()
    global timer1
    timer1.cancel()

if __name__ == '__main__':  # Program starting from here
    setup()
    try:
        loop()
    except KeyboardInterrupt:
        destroy()

Code Explanation

def stateChange():
    global gameState
    global counter
    global timer1
    if gameState == 0:
        counter = 0
        time.sleep(1)
        timer()
    elif gameState ==1:
        timer1.cancel()
        time.sleep(1)
    gameState = (gameState+1)%2

The game is divided into two modes:

gameState=0 is the “start” mode, in which the time is timed and displayed on the segment display, and the tilting switch is shaken to enter the “show” mode.

GameState =1 is the “show” mode, which stops the timing and displays the time on the segment display. Shaking the tilt switch again will reset the timer and restart the game.

def loop():
    global counter
    currentState = 0
    lastState = 0
    while True:
        display()
        currentState=GPIO.input(sensorPin)
        if (currentState == 0) and (lastState == 1):
            stateChange()
        lastState=currentState

Loop() is the main function. First, the time is displayed on the 4-bit segment display and the value of the tilt switch is read. If the state of the tilt switch has changed, stateChange() is called.

def timer():
    global counter
    global timer1
    timer1 = threading.Timer(0.01, timer)
    timer1.start()
    counter += 1

After the interval reaches 0.01s, the timer function is called; add 1 to counter, and the timer is used again to execute itself repeatedly every 0.01s.

Phenomenon Picture

_images/image278.jpeg