Product Name: TB371 24pcs Universal DC 0-48V 4 key push button switch Keyboard Matrix Board for PIC PLC ARM FPGA CPLD MCU Development Board
Packing list:
24 PCS 4 key push button switch Module,
Description:
Can be inserted directly into Arduiuo uno mega2560,Ideal for linking up to your Arduiuo UNO Pro Mini Nano Mega2560 Breadboard raspberry pi etc,or others MCU ( PLC AVR STM32 ARM PIC AT89C51 MSP430 STM8 Xilinx Altera Lattice FPGA CPLD etc.)
1 4-button Common Cathode key module .
2 '' GND K1 K2 K3 K4'' 4 PIN OUT 2.54mm
3Working voltage: Can be DC 1.2V 1.8V 2.5V 3V 3.3V 4.5V 5V 9V 12V 24V 36V 48V
4 Size: 12.8mm x 33mm
Arduiuo uno/mega2560 Code
//******************************************************//
/*
Arduiuo_4key_uart
This example code is in the public domain.
*/
// Define key pin
int K1 = 13,
int K2 = 12,
int K3 = 11,
int K4 = 10,
// variables will change:
int buttonState = 0, // variable for reading the pushbutton status
// the setup routine runs once when you press reset:
void setup() {
// initialize the keys pin as an input.
pinMode(K1, INPUT),
pinMode(K2, INPUT),
pinMode(K3, INPUT),
pinMode(K4, INPUT),
//Activate key pin internal pull-up resistors
digitalWrite(K1, HIGH),
digitalWrite(K2, HIGH),
digitalWrite(K3, HIGH),
digitalWrite(K4, HIGH),
// initialize serial communications at 9600 bps:
Serial.begin(9600),
}
// the loop routine runs over and over again forever:
void loop() {
buttonState = digitalRead(K1),
if(!buttonState)Serial.print(''k1 /n'' ),
do
{
buttonState = digitalRead(K1),
}
while(!buttonState),//Wait button release
buttonState = digitalRead(K2),
if(!buttonState)Serial.print(''k2 /n'' ),
do
{
buttonState = digitalRead(K2),
}
while(!buttonState),//Wait button release
buttonState = digitalRead(K3),
if(!buttonState)Serial.print(''k3 /n'' ),
do
{
buttonState = digitalRead(K3),
}
while(!buttonState),//Wait button release
buttonState = digitalRead(K4),
if(!buttonState)Serial.print(''k4 /n'' ),
do
{
buttonState = digitalRead(K4),
}
while(!buttonState),//Wait button release
delay(100),
}
//******************************************************//
Circuit schematics :
Specifications
Material
PCB
Brand Name
eletechsup
Origin
Mainland China
key keypad
4 button
Output Level
Low level
Operating Voltage
DC 0-48V