.. note:: Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts. **Why Join?** - **Expert Support**: Solve post-sale issues and technical challenges with help from our community and team. - **Learn & Share**: Exchange tips and tutorials to enhance your skills. - **Exclusive Previews**: Get early access to new product announcements and sneak peeks. - **Special Discounts**: Enjoy exclusive discounts on our newest products. - **Festive Promotions and Giveaways**: Take part in giveaways and holiday promotions. 👉 Ready to explore and create with us? Click [|link_sf_facebook|] and join today! 3.1.14 GAME– Not Not ======================= Introduction -------------------- In this lesson, we will make an interesting game device, and we call it \"Not Not\". During the game, the dot matrix will refresh an arrow randomly. What you need to do is to press the button in the opposite direction of the arrow within a limited time. If the time is up, or if the button in the same direction as the arrow is pressed, you are out. This game can really practice your reverse thinking, and now shall we have a try? Components --------------- .. image:: img/list_GAME_Not_Not.png :align: center Schematic Diagram ----------------------- ============ ======== ======== === T-Board Name physical wiringPi BCM GPIO17 Pin 11 0 17 GPIO18 Pin 12 1 18 GPIO27 Pin 13 2 27 GPIO20 Pin 38 28 20 GPIO26 Pin 37 25 26 ============ ======== ======== === .. image:: img/Schematic_three_one14.png :align: center Experimental Procedures ----------------------------- **Step 1:** Build the circuit. .. image:: img/image280.png :width: 800 **For C Language Users** ^^^^^^^^^^^^^^^^^^^^^^^^^^ **Step 2:** Go to the folder of code. .. raw:: html .. code-block:: cd ~/davinci-kit-for-raspberry-pi/c/3.1.14/ **Step 3**: Compile. .. raw:: html .. code-block:: gcc 3.1.14_GAME_NotNot.c -lwiringPi **Step 4**: Run. .. raw:: html .. code-block:: sudo ./a.out After the program starts, a left or right arrow will be refreshed at random on the dot matrix. What you need to do is to press the button in the opposite direction of the arrow within a limited time. Then \"**√**\" appears on the dot matrix. If the time is up, or if the button in the same direction as the arrow is pressed, you are out and the dot matrix displays \"x\". You can also add 2 new buttons or replace them with Joystick keys for up, down, left and right— 4 directions to increase the difficulty 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 :ref:`install_wiringpi`. **Code Explanation** Based on :ref:`1.1.6_matrix`, this lesson adds **2** buttons to make an amusing game device. The whole program process is as below: 1. Randomly select an arrow direction and generate **timer 1**. 2. Display the arrow image on the dot matrix. 3. Judge the button input. If the button is pressed or **timer 1** reminds time’s up, judgement starts. 4. Display the image on the basis of a judging result; meanwhile, generate **timer 2**. 5. Rerun **step 1** when **timer 2** reminds time’s up. .. code-block:: c struct GLYPH{     char *word;     unsigned char code[8]; }; struct GLYPH arrow[2]= {     {"right",{0xFF,0xEF,0xDF,0x81,0xDF,0xEF,0xFF,0xFF}},     // {"down",{0xFF,0xEF,0xC7,0xAB,0xEF,0xEF,0xEF,0xFF}},     // {"up",{0xFF,0xEF,0xEF,0xEF,0xAB,0xC7,0xEF,0xFF}},         {"left",{0xFF,0xF7,0xFB,0x81,0xFB,0xF7,0xFF,0xFF}} }; struct GLYPH check[2]= {     {"wrong",{0xFF,0xBB,0xD7,0xEF,0xD7,0xBB,0xFF,0xFF}},     {"right",{0xFF,0xFF,0xF7,0xEB,0xDF,0xBF,0xFF,0xFF}} }; GLYPH structure works like a dictionary: the **word** attribute corresponds to the **key** on the dictionary; the **code** attribute corresponds to the **value**. Here, code is used to store an array for dot matrix to display images (an 8x8 bit array). Here, the array **arrow** can be used to display the arrow pattern in up, down, left and right directions on the LED dot matrix. Now **down** and **up** are commented and uncomment them if needed. The array **check** is used to display these two images: \"**×**\" and \"**√**\". .. code-block:: c char *lookup(char *key,struct GLYPH *glyph,int length){     for (int i=0;i>i);         hc595_out();     } } Display the specified pattern on the dot matrix. .. code-block:: c void createGlyph(){     srand(time(NULL));     int i=rand()%(sizeof(arrow)/sizeof(arrow[0]));     waypoint=arrow[i].word;     stage="PLAY";     alarm(2); } The function **createGlyph()** is used to randomly select a direction (the word attribute of an element in the array **arrow[]:** \"**left**\", \"**right**\"... ). Set the stage as \"PLAY\" and start a 2-second alarm clock function. **srand(time(NULL)):** Initializes random seeds that are from the system clock. **(sizeof(arrow)/sizeof(arrow[0])):** Get the length of the array, the outcome is 2. **rand()%2:** The remainder is **0** or **1,** gotten from dividing a generated random number by 2. **waypoint=arrow[i].word:** The outcome should be \"right\" or \"left\". .. code-block:: c void checkPoint(char *inputKey){     alarm(0)==0;     if(inputKey==waypoint||inputKey=="empty")     {         waypoint="wrong";     }     else{         waypoint="right";     }     stage="CHECK";     alarm(1); } checkPoint() is used to check the button input; if the button is not pressed or the button in the same direction as the arrow is pressed, the outcome of the waypoint is wrong and \"**x**\" appears on the dot matrix. Otherwise, the waypoint is right and dot matrix displays \"**√**\". Here the **stage** is **CHECK,** and there can be set a 1-second alarm clock function. alarm() is also called \"alarm clock\", in which a timer can be set, and it sends **SIGALRM** signals to the progress when the defined time is up. .. code-block:: c void getKey(){     if (digitalRead(AButtonPin)==1&&digitalRead(BButtonPin)==0)     {checkPoint("right");}     else if (digitalRead(AButtonPin)==0&&digitalRead(BButtonPin)==1)     {checkPoint("left");} } getKey() reads the states of the these two buttons; if the right button is pressed, the parameter of the function checkPoint() is **right** and if the left button is pressed, the parameter is **left**. .. code-block:: c void timer(){     if (stage=="PLAY"){         checkPoint("empty");     }     else if(stage=="CHECK"){         createGlyph();     } } Previously, timer() was called when set as the alarm() time’s up. Then under the \"PLAY\" mode, checkPoint() is to be called to judge the outcome. If the program is set to \"CHECK\" mode, the function createGlyph() should be called to select new patterns. .. code-block:: c void main(){     setup();     signal(SIGALRM,timer);     createGlyph();     char *code = NULL;     while(1){         if (stage == "PLAY")         {             code=lookup(waypoint,arrow,sizeof(arrow)/sizeof(arrow[0]));             display(code);             getKey();         }         else if(stage == "CHECK")         {             code = lookup(waypoint,check,sizeof(check)/sizeof(check[0]));             display(code);         }     } } The working of the function signal(SIGALRM,timer): calling the timer() function when a SIGALRM signal (generated by the alarm clock function alarm()) is received. When the program starts, call createGlyph() one time at first and then start the loop. In the loop: under PLAY mode, the dot matrix displays arrow patterns and check the button state; if under CHECK mode, what is displayed is \"**x**\" or \"**√**\". **For Python Language Users** ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ **Step 2**: Get into the folder of code. .. raw:: html .. code-block:: cd ~/davinci-kit-for-raspberry-pi/python **Step 3**: Run. .. raw:: html .. code-block:: sudo python3 3.1.14_GAME_NotNot.py After starting the program, on the dot matrix appears an arrow pointing to the right or the left. What you need to do is to press the button in the opposite direction of the arrow within a limited time. Then \"**√**\" appears on the dot matrix. If the time is up, or if the button in the same direction as the arrow is pressed, you are out and the dot matrix displays \"x\". You can also add 2 new buttons or replace them with Joystick keys for up, down, left and right— 4 directions to increase the difficulty 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``. .. raw:: html .. code-block:: python import RPi.GPIO as GPIO import time import threading import random SDI = 17 RCLK = 18 SRCLK = 27 timerPlay = 0 timerCheck = 0 AButtonPin = 20 BButtonPin = 26 waypoint = "NULL" stage = "NULL" arrow={ #"down" :[0xFF,0xEF,0xC7,0xAB,0xEF,0xEF,0xEF,0xFF], #"up":[0xFF,0xEF,0xEF,0xEF,0xAB,0xC7,0xEF,0xFF], "right" : [0xFF,0xEF,0xDF,0x81,0xDF,0xEF,0xFF,0xFF], "left":[0xFF,0xF7,0xFB,0x81,0xFB,0xF7,0xFF,0xFF] } check={ "wrong":[0xFF,0xBB,0xD7,0xEF,0xD7,0xBB,0xFF,0xFF], "right":[0xFF,0xFF,0xF7,0xEB,0xDF,0xBF,0xFF,0xFF] } def setup(): GPIO.setmode(GPIO.BCM) # Number GPIOs by its BCM location GPIO.setup(SDI, GPIO.OUT) GPIO.setup(RCLK, GPIO.OUT) GPIO.setup(SRCLK, GPIO.OUT) GPIO.output(SDI, GPIO.LOW) GPIO.output(RCLK, GPIO.LOW) GPIO.output(SRCLK, GPIO.LOW) GPIO.setup(AButtonPin,GPIO.IN) GPIO.setup(BButtonPin,GPIO.IN) # Shift the data to 74HC595 def hc595_shift(dat): for bit in range(0, 8): GPIO.output(SDI, 0x80 & (dat << bit)) GPIO.output(SRCLK, GPIO.HIGH) GPIO.output(SRCLK, GPIO.LOW) def display(glyphCode): for i in range(0, 8): hc595_shift(glyphCode[i]) hc595_shift(0x80>>i) GPIO.output(RCLK, GPIO.HIGH) GPIO.output(RCLK, GPIO.LOW) def creatGlyph(): global waypoint global stage global timerPlay waypoint=random.choice(list(arrow.keys())) stage = "PLAY" timerPlay = threading.Timer(2.0, timeOut) timerPlay.start() def checkPoint(inputKey): global waypoint global stage global timerCheck if inputKey == "empty" or inputKey == waypoint: waypoint = "wrong" else: waypoint = "right" timerPlay.cancel() stage = "CHECK" timerCheck = threading.Timer(1.0, creatGlyph) timerCheck.start() def timeOut(): checkPoint("empty") def getKey(): if GPIO.input(AButtonPin)==1 and GPIO.input(BButtonPin)==0: checkPoint("right") elif GPIO.input(AButtonPin)==0 and GPIO.input(BButtonPin)==1: checkPoint("left") def main(): creatGlyph() while True: if stage == "PLAY": display(arrow[waypoint]) getKey() elif stage == "CHECK": display(check[waypoint]) def destroy(): global timer1 GPIO.cleanup() timerPlay.cancel() # cancel the timer timerCheck.cancel() if __name__ == '__main__': setup() try: main() except KeyboardInterrupt: destroy() **Code Explanation** Based on :ref:`1.1.6_matrix`, this lesson adds **2** buttons to make an amusing game device. The whole program process is as below: .. image:: img/notnot3.png :width: 800 1. Randomly select an arrow direction and generate **timer 1**. 2. Display the corresponding arrow image on the dot matrix. 3. Judge the button input. If the button is pressed or **timer 1** reminds time’s up, judgement starts. 4. Display the image on the basis of a judging result; meanwhile, generate **timer 2**. 5. Rerun **step 1** when **timer 2** reminds time’s up. .. code-block:: python def main():     creatGlyph()     while True:         if stage == "PLAY":             display(arrow[waypoint])             getKey()         elif stage == "CHECK":             display(check[waypoint]) Main() contains the whole running process. When the program starts, call createGlyph() one time at first and then start the loop. In the loop: under PLAY mode, the dot matrix displays arrow patterns and check the button state; if under CHECK mode, what is displayed is \"**x**\" or \"**√**\". .. code-block:: python arrow={     #"down" :[0xFF,0xEF,0xC7,0xAB,0xEF,0xEF,0xEF,0xFF],     #"up":[0xFF,0xEF,0xEF,0xEF,0xAB,0xC7,0xEF,0xFF],     "right" : [0xFF,0xEF,0xDF,0x81,0xDF,0xEF,0xFF,0xFF],         "left":[0xFF,0xF7,0xFB,0x81,0xFB,0xF7,0xFF,0xFF] } check={     "wrong":[0xFF,0xBB,0xD7,0xEF,0xD7,0xBB,0xFF,0xFF],     "right":[0xFF,0xFF,0xF7,0xEB,0xDF,0xBF,0xFF,0xFF] } Here, the **dictionary** arrow can be used to display the arrow pattern in up, down, left and right directions on the LED dot matrix. Now down and up are commented and uncomment them if needed. The **dictionary** check is used to display these two images: \"**×**\" and \"**√**\". .. code-block:: python def display(glyphCode):     for i in range(0, 8):         hc595_shift(glyphCode[i])         hc595_shift(0x80>>i)         GPIO.output(RCLK, GPIO.HIGH)         GPIO.output(RCLK, GPIO.LOW) Display the specified pattern on the dot matrix. .. code-block:: python def creatGlyph():     global waypoint     global stage     global timerPlay         waypoint=random.choice(list(arrow.keys()))     stage = "PLAY"     timerPlay = threading.Timer(2.0, timeOut)       timerPlay.start() The function **createGlyph()** is used to randomly select a direction (the word attribute of an element in the array **arrow[]:** \"**left**\", \"**right**\"... ). Set the stage as \"PLAY\" and start a 2-second alarm clock function. **arrow.keys():** Select the keys \"right\"and \"left\" in the arrow array. **list(arrow.keys()):** Combine these keys into an array. **random.choice(list(arrow.keys())):** Randomly select an element in the array. So, The outcome of **waypoint=random.choice(list(arrow.keys()))** should be \"right\" or \"left\". .. code-block:: python def checkPoint(inputKey):     global waypoint     global stage     global timerCheck         if inputKey == "empty" or inputKey == waypoint:         waypoint = "wrong"     else:         waypoint = "right"     timerPlay.cancel()     stage = "CHECK"     timerCheck = threading.Timer(1.0, creatGlyph)     timerCheck.start()   checkPoint() is to detect the current state of button input: If no button is pressed or the button in the same direction as the the arrow is pressed, the assigned value of the **``waypoint``** is **``wrong``** and there displays ``x`` on the dot matrix. Otherwise, the waypoint is right and \"**√**\" appears. Now the stage is **CHECK** and start a 1-second timer **timerCheck** to call the function creatGlyph() in a second. .. code-block:: python def timeOut():       checkPoint("empty") In the function timeout(), set the parameter of checkPoint() as \"**empty**\". .. code-block:: python def getKey():     if GPIO.input(AButtonPin)==1 and GPIO.input(BButtonPin)==0:         checkPoint("right")     elif GPIO.input(AButtonPin)==0 and GPIO.input(BButtonPin)==1:         checkPoint("left") getKey() reads the state of these two buttons, and if the right button is pressed, the parameter of checkPoint() is **right**; if the left button is pressed, the parameter is **left**. Phenomenon Picture ------------------------ .. image:: img/image281.jpeg :align: center