How it works<\/h2>\n
Here’s a figure that describes exactly how everything works together:<\/p>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/06\/how-it-works.png?resize=755%2C573&quality=100&strip=all&ssl=1\")
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If you like Arduino projects and you want to build more, we recommend getting the Arduino Step-by-step Projects \u2013 Build 25 Projects course<\/a>.<\/p>\n The Arduino can be configured to emulate a keyboard and perform useful tasks. Attaching a pushbutton to an Arduino digital pin and with a button press, you can write a password<\/a>, copy+paste, up\/down volume, up\/down screen brightness, etc\u2026<\/p>\n Although boards like the Arduino UNO can\u2019t do this by default if you flash a new bootloader, you can make the Arduino UNO board turn into a USB HID keyboard.<\/p>\n An Arduino Uno\/Mega has two microcontrollers: ATmega328 and 16u2. The 16u2 is normally used for USB to Serial communication. We can also use it as standalone AVR Microcontroller with (or without) USB functions as well.<\/p>\n HoodLoader2 gives you the option to reprogram the 16u2 of a normal Arduino Uno\/Mega R3 with custom sketches. This means you can use the 16u2 as a normal USB AVR like an Arduino Leonardo board. You have a full compatible USB-HID core.<\/p>\n You can prepare your Arduino UNO or Arduino Mega to act as a keyboard with the HoodLoader2<\/a> bootloader by following the instructions in their official Wiki page<\/a>.<\/p>\n Supported Arduino boards using Arduino IDE 1.6.7 or higher:<\/p>\n Here\u2019s a complete list of the components you need for this project:<\/p>\n You can use the preceding links or go directly to MakerAdvisor.com\/tools<\/a> to find all the parts for your projects at the best price!<\/p> To use your Arduino as a keyboard, you need to install the HID Library.<\/p>\n Installing the HID Library<\/strong><\/p>\n Copy the following code to your Arduino IDE and upload it to your Arduino board:<\/p>\nArduino UNO or Mega as a USB HID keyboard<\/h2>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/06\/16u.jpg?resize=517%2C467&quality=100&strip=all&ssl=1\")
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Parts required<\/h2>\n
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![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/06\/demonstration.jpg?resize=484%2C382&quality=100&strip=all&ssl=1\")
<\/p>\nUploading code<\/h2>\n
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HID-master<\/strong><\/del> to HID<\/strong><\/li>\n \/*\n * Author: Emmanuel Odunlade \n * Complete Project Details http:\/\/randomnerdtutorials.com\n *\/\n \n#include <HID.h>\/\/ include the library \n\nint swipe = 0;\/\/slide\nboolean left = false;\nboolean right = false;\nint maxD = 5;\/\/(in cm) maximum distance from ultrasonic at which the obstruction will be considered a gesture\nlong int lastTouch = -1;\nint resetAfter = 1000;\/\/ms\nint afterslideDelay = 500;\/\/\nint slideleft_Begin = -1;\nint slideNone = 0;\nint slideright_Begin =1;\n\n\/\/Declaring the connected pins\nint lLed = 7;\nint rLed = 6;\nconst int lEcho = 2;\nconst int lTrig = 3;\nconst int rEcho = 4;\nconst int rTrig = 5;\n\nvoid setup(){\n pinMode(lLed,OUTPUT);\n pinMode(rLed,OUTPUT);\n pinMode(rEcho,INPUT); \n pinMode(rTrig,OUTPUT);\n pinMode(lEcho,INPUT);\n pinMode(lTrig,OUTPUT);\n \n Serial.begin(9600);\n \/\/ Sends a clean report to the host. This is important because\n \/\/ the 16u2 of the Uno\/Mega is not turned off while programming\n \/\/ so you want to start with a clean report to avoid strange bugs after reset.\n pressRawKeyboard(0, 0);\n}\n\n\/\/get distance\n\/\/echo is input, trigger is output\nunsigned long measureD(int input, int output){\n digitalWrite(output, HIGH);\n delayMicroseconds(10); \n digitalWrite(output, LOW);\n long range= pulseIn(input, HIGH);\n int distance= range \/ 29 \/ 2;\/\/ to get distance in cm\n return distance;\n}\n\n\/\/\nboolean act (int input, int output, int led){\n int d = measureD(input,output);\n boolean pinActivated = false;\n if (d < maxD){\n digitalWrite(led,HIGH);\n pinActivated = true;\n }\n else{\n digitalWrite(led,LOW);\n pinActivated = false;\n }\n return pinActivated;\n}\n\nvoid slideNow(char directn){\n if ('R' == directn)\n {\n \/\/ press the right rrow key\n \/\/Serial.println("F");\n pressRawKeyboard(0,RAW_KEYBOARD_RIGHT_ARROW); \/\/modifiers + key\n pressRawKeyboard(0, 0); \/\/ release! Important\n }\n if ('L' == directn)\n {\n \/\/press the left arrow key\n \/\/Serial.println("B"); for debug\n pressRawKeyboard(0,RAW_KEYBOARD_LEFT_ARROW); \/\/ \/\/modifiers + key\n pressRawKeyboard(0, 0); \/\/ release! Important\n }\n delay(afterslideDelay);\n swipe = slideNone;\n}\n\nvoid pressRawKeyboard(uint8_t modifiers, uint8_t key){\n uint8_t keys[8] = { \n modifiers, 0, key, 0, 0, 0, 0, 0 }; \/\/modifiers, reserved, key[0]\n HID_SendReport(HID_REPORTID_KeyboardReport, keys, sizeof(keys));\n}\n\n\nvoid loop(){\n left = act(lEcho,lTrig,lLed);\n right = act(rEcho,rTrig,rLed);\n if (left || right){\n lastTouch = millis();\n }\n if (millis() - lastTouch > resetAfter){\n swipe = 0;\n \/\/serial.println(@reset slide& timer);\n }\n if (swipe >= slideNone){\n if ((left)&&(!right)){\n swipe = slideright_Begin;\n }\n if ((right)&&(swipe == slideright_Begin)){\n slideNow('R');\n }\n }\n if (swipe <= slideNone ){\n if ((right)&&(!left)){\n swipe = slideleft_Begin;\n }\n if ((left) && (swipe == slideleft_Begin)){\n slideNow('L');\n }\n }\n delay(50);\n }\n \n<\/code><\/pre>\n\t
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/06\/SlideSwipe_f.png?resize=701%2C581&quality=100&strip=all&ssl=1\")
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