DFR0075

  ADKeyboard Module (SKU: DFR0075) ADKeyboard Module (SKU: DFR0075) Contents      1 Introduction 2 Specifications 3 Pin out Diagram 4 Wiring Diagram 5 Sample Code Introduction This keyboard uses an analog input to read the five key state which saves IO resource for the Arduino. It can be used together with our IO Expansion Shield_For Arduino(V5)_(SKU:_DFR0088) to make amazing interactive project. Specifications    Supply voltage: 5V Interface: Analog Size: 40x33mm Pin out Diagram Wiring Diagram Sample Code //ADKeyboard Module //Developed by DFRobot.com //Last modified 30/11/2011 //Version 1.0 int adc_key_val[5] ={600,650, 700, 800, 900 }; int NUM_KEYS = 5; int adc_key_in; int key=-1; int oldkey=-1; void setup() { pinMode(13, OUTPUT); //we'll use the debug LED to output a heartbeat Serial.begin(9600); // 9600 bps } void loop() { adc_key_in = analogRead(0); // read the value from the sensor digitalWrite(13,LOW); key = get_key(adc_key_in); if (key != oldkey) // convert into key press // if keypress is detected { delay(50); // wait for debounce time adc_key_in = analogRead(0); key = get_key(adc_key_in); if (key != oldkey) { oldkey = key; if (key >=0){ digitalWrite(13,HIGH); switch(key) { // read the value from the sensor // convert into key press case 0:Serial.println("S1 OK"); break; case 1:Serial.println("S2 OK"); break; case 2:Serial.println("S3 OK"); break; case 3:Serial.println("S4 OK"); break; case 4:Serial.println("S5 OK"); break; } } } } delay(100); } // Convert ADC value to key number int get_key(unsigned int input) { int k; for (k = 0; k < NUM_KEYS; k++) { if (input < adc_key_val[k]) { return k; } } if (k >= NUM_KEYS)k = -1; // No valid key pressed return k; }    Powered By DFRobot © 2008-2017