{"product_id":"3pcs-keypad-4-button-key-module-switch-keyboard-for-uno-mega2560-breadboard","title":"3pcs Keypad 4 Button Key Module Switch Keyboard for UNO MEGA2560 Breadboard","description":"\u003cdiv\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eDescription: \u003c\/strong\u003e\u003c\/span\u003e\u003c\/div\u003e\u003cdiv\u003e \u003c\/div\u003e\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eCan be inserted directly into uno mega2560, Ideal for linking up to your   UNO Mini Nano Mega2560 Breadboard etc, or others MCU ( AVR STM32 ARM PIC AT89C51 STC MSP430 STM8 FPGA CPLD etc.) \u003c\/span\u003e\u003c\/div\u003e\u003cdiv\u003e \u003c\/div\u003e\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e4-button Common Cathode key module\u003c\/span\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eGND \"K1 K2 K3 K4\" 4 PIN OUT 2.54mm\u003c\/span\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eSize: 12.7MM x 33MM.\u003c\/span\u003e\u003c\/div\u003e\u003cdiv\u003e \u003c\/div\u003e\u003cdiv\u003e\n\u003cspan style=\"font-size:14px;\"\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003eCircuit schematics:\u003c\/strong\u003e\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"http:\/\/img.staticbg.com\/images\/oaupload\/banggood\/images\/3D\/0D\/bd9a964e-9b5d-41e3-bada-7bd7ee5f1770.jpg\" style=\"width: 425px; height: 472px;\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cspan style=\"font-size:16px;\"\u003e\u003cstrong\u003ePackage includes:\u003c\/strong\u003e\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e3 x Keyboard\u003c\/span\u003e\u003cbr\u003e\u003cbr\u003e\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003euno\/mega2560 Code\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/******************************************************\/\/\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/*\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e_4key_uart\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eThis example code is in the public domain.\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e*\/\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ Define key pin\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eint K1 = 13;\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eint K2 = 12;\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eint K3 = 11;\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eint K4 = 10;\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ variables will change:\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eint buttonState = 0; \/\/ variable for reading the pushbutton status\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ the setup routine runs once when you press reset:\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003evoid setup() {\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ initialize the keys pin as an input.\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003epinMode(K1, INPUT);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003epinMode(K2, INPUT);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003epinMode(K3, INPUT);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003epinMode(K4, INPUT);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/Activate key pin internal pull-up resistors\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edigitalWrite(K1, HIGH);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edigitalWrite(K2, HIGH);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edigitalWrite(K3, HIGH);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edigitalWrite(K4, HIGH);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ initialize serial communications at 9600 bps:\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eSerial.begin(9600);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e\/\/ the loop routine runs over and over again forever:\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003evoid loop() {\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K1);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eif(!buttonState)Serial.print(\"k1 n\" );\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edo\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e{\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K1);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ewhile(!buttonState);\/\/Wait button release\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K2);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eif(!buttonState)Serial.print(\"k2 n\" );\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edo\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e{\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K2);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ewhile(!buttonState);\/\/Wait button release\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K3);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eif(!buttonState)Serial.print(\"k3 n\" );\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edo\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e{\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K3);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ewhile(!buttonState);\/\/Wait button release\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K4);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003eif(!buttonState)Serial.print(\"k4 n\" );\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edo\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e{\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ebuttonState = digitalRead(K4);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003ewhile(!buttonState);\/\/Wait button release\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003edelay(100);\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e}\u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e    \u003c\/span\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cspan style=\"font-size:14px;\"\u003e \/\/******************************************************\/\/\u003c\/span\u003e\u003c\/div\u003e\n\u003c\/div\u003e\u003cbr\u003e\u003cbr type=\"_moz\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/F2\/2B\/509c0103-4ac7-4b41-bb19-0dd70a1ca28a.jpg\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/8F\/5D\/1927d82b-aa57-475c-bb59-cb6ed342687e.jpg\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/8A\/D0\/d5ff4714-4b13-41ba-8aff-1c944b9bf679.jpg\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/7E\/A7\/02295cf5-f363-43c6-8d4a-96ceff4b17d9.jpg\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/F6\/15\/ea27e5d5-2e28-410d-8874-519f412cc170.jpg\"\u003e\u003cbr\u003e\u003cbr\u003e\u003cimg alt=\"\" src=\"https:\/\/imgaz.staticbg.com\/images\/oaupload\/ser1\/banggood\/images\/99\/A0\/a7297fb7-fd9d-413b-9e00-63dc24b9e385.jpg\"\u003e","brand":"Electronic Pro","offers":[{"title":"Default Title","offer_id":35468033261724,"sku":"1590011","price":210.06,"currency_code":"ZAR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/2787\/9162\/products\/509c0103-4ac7-4b41-bb19-0dd70a1ca28a.jpg?v=1597149181","url":"https:\/\/electronic-pro-south-africa.myshopify.com\/products\/3pcs-keypad-4-button-key-module-switch-keyboard-for-uno-mega2560-breadboard","provider":"Electronic Pro ","version":"1.0","type":"link"}