I trying to write a program to count every time a button is pushed and display on a 4 digit-7 segment LED display. Through the serial monitor, the code registers the button push, but the LED display doesn't even light up. Honestly, I don't know how to test it. The display has 5 pins off the side. 5V for power and GND for ground are together and DIN, LOAD/CS, AND CLK grouped together. I am only connecting the DIN to the TX on the arduino pin. Do the other have to be connected as well and if so where?
#include <LiquidCrystal.h>
#include <SoftwareSerial.h> //for software serial communication
#define txPin 1 //change to your serial port on Arduino board
#define rxPin 0 //not used but is required
SoftwareSerial mySerial = SoftwareSerial(rxPin, txPin);
int buttonPressCount;
const int buttonPin = 9; //the pin that the pushbutton is attached to
int buttonPushCounter = 0; //counter for the number of button presses
int buttonState = 0; //current state of the button
int lastButtonState = 0; //previous state of the button
void setup() {
pinMode(buttonPin, INPUT); //initialize the button pin as a input
Serial.begin(9600); //initialize serial communication
pinMode(txPin, OUTPUT);
//the following resets the board, changes the brightness to 100%, and sets the board to '0000':
mySerial.begin(9600);
mySerial.write((byte)0x7A); //special character
mySerial.write((byte)0x00); //set brightness to full
mySerial.write((byte)0x76); //reset board
mySerial.print(0); //send '0' character
mySerial.print(0); //send '0' character
mySerial.print(0); //send '0' character
mySerial.print(0); //send '0' character
}
void loop(){
buttonState = digitalRead(buttonPin); //read the pushbutton input pin
// compare the buttonState to its previous state
if (buttonState != lastButtonState) {
// if the state has changed, increment the counter
if (buttonState == HIGH) {
// if the current state is HIGH then the button
// went from off to on:
buttonPushCounter++;
Serial.print("number of button pushes: ");
Serial.println(buttonPushCounter, DEC);
updateDisplay(buttonPushCounter); //function to update the display 'requires button press count'
}
}
lastButtonState = buttonState; // save the current state as the last state, for next time through the loop
}
void updateDisplay(int buttonPushCounter){
String intString = String(buttonPushCounter); //changes integer to a string
char displayChars[4]; //create array to hold the four numbers
int stringLength = intString.length(); //get length of the string
//the following will determine if the button press count variable has 1, 2, 3, or 4 numbers in it
//and will fill the empty spaces with '0'. so if the button press count variable is '29' it will end up being '0029':
if(stringLength == 4){
displayChars[0] = intString.charAt(0);
displayChars[1] = intString.charAt(1);
displayChars[2] = intString.charAt(2);
displayChars[3] = intString.charAt(3);
}
else if(stringLength == 3){
displayChars[0] = 0;
displayChars[1] = intString.charAt(0);
displayChars[2] = intString.charAt(1);
displayChars[3] = intString.charAt(2);
}
else if(stringLength == 2){
displayChars[0] = 0;
displayChars[1] = 0;
displayChars[2] = intString.charAt(0);
displayChars[3] = intString.charAt(1);
}
else if(stringLength == 1){
displayChars[0] = 0;
displayChars[1] = 0;
displayChars[2] = 0;
displayChars[3] = intString.charAt(0);
}
mySerial.write((byte)0x76); //Reset board
mySerial.write((byte)0x76); //Reset board
mySerial.print(displayChars[0]); //Send '0' character
mySerial.print(displayChars[1]); //Send '0' character
mySerial.print(displayChars[2]); //Send '0' character
mySerial.print(displayChars[3]); //Send '0' character
delay(100); //this will make it so you don't get double counts. you could also use this to avoid someone pressing the button repeatedly 'for fun!'
}
