Hello I'm building something for my next door neighbors son he is special needs and my project is a basic put buttons with 10 buttons but to get started i wanted to use a attiny85 or attiny84 i have many of them but sense it is limited on pins would need to do a multiple button single wire and also what is added is just a simple rx tx lcd i do have the lcd and 3 buttons working but needed to do 10 buttons. I found a sketch online to help me with that but i don't understand it. also it comes from a instructables site. Instructables multiplepush buttons in the sketch i seen this
const int BUTTON1LOW = 970;
const int BUTTON1HIGH = 1024;
const int BUTTON2LOW = 850;
const int BUTTON2HIGH = 950;
const int BUTTON3LOW = 700;
const int BUTTON3HIGH = 800;
const int BUTTON4LOW = 400;
const int BUTTON4HIGH = 650;
const int BUTTON5LOW = 250;
const int BUTTON5HIGH = 350;
i do not understand what this means. here is the sketch
/*
Debounce
Each time the input pin goes from LOW to HIGH (e.g. because of a push-button
press), the output pin is toggled from LOW to HIGH or HIGH to LOW. There's
a minimum delay between toggles to debounce the circuit (i.e. to ignore
noise).
created 28 October 2009
by Riaan Cornelius
*/
// constants won't change. They're used here to
// set pin numbers:
const int buttonPin = 0; // the number of the pushbutton pin
const int ledPin = 13; // the number of the LED pin for testing
const int BUTTON1 = 1;
const int BUTTON2 = 2;
const int BUTTON3 = 3;
const int BUTTON4 = 4;
const int BUTTON5 = 5;
const int BUTTON1LOW = 970;
const int BUTTON1HIGH = 1024;
const int BUTTON2LOW = 850;
const int BUTTON2HIGH = 950;
const int BUTTON3LOW = 700;
const int BUTTON3HIGH = 800;
const int BUTTON4LOW = 400;
const int BUTTON4HIGH = 650;
const int BUTTON5LOW = 250;
const int BUTTON5HIGH = 350;
// Variables will change:
int ledState = HIGH; // the current state of the output pin
int buttonState; // the current reading from the input pin
int lastButtonState = LOW; // the previous reading from the input pin
// the following variables are long's because the time, measured in miliseconds,
// will quickly become a bigger numbeitr than can be stored in an int.
long lastDebounceTime = 0; // the last time the output pin was toggled
long debounceDelay = 50; // the debounce time; increase if the output flickers
void setup() {
pinMode(buttonPin, INPUT);
pinMode(ledPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
// read the state of the switch into a local variable:
int reading = analogRead(buttonPin);
int tmpButtonState = LOW; // the current reading from the input pin
if(reading>BUTTON5LOW && reading<BUTTON5HIGH){
//Read switch 5
tmpButtonState = BUTTON5;
}else if(reading>BUTTON4LOW && reading<BUTTON4HIGH){
//Read switch 4
tmpButtonState = BUTTON4;
}else if(reading>BUTTON3LOW && reading<BUTTON3HIGH){
//Read switch 3
tmpButtonState = BUTTON3;
}else if(reading>BUTTON2LOW && reading<BUTTON2HIGH){
//Read switch 2
tmpButtonState = BUTTON2;
}else if(reading>BUTTON1LOW && reading<BUTTON1HIGH){
//Read switch 1
tmpButtonState = BUTTON1;
}else{
//No button is pressed;
tmpButtonState = LOW;
}
// check to see if you just pressed the button
// (i.e. the input went from LOW to a buttonState), and you've waited
// long enough since the last press to ignore any noise:
// If the switch changed, due to noise or pressing:
if (tmpButtonState != lastButtonState) {
// reset the debouncing timer
lastDebounceTime = millis();
}
if ((millis() - lastDebounceTime) > debounceDelay) {
// whatever the reading is at, it's been there for longer
// than the debounce delay, so take it as the actual current state:
buttonState = tmpButtonState;
Serial.println(buttonState);
}
// save the reading. Next time through the loop,
// it'll be the lastButtonState:
lastButtonState = tmpButtonState;
// set the LED using the state of the button for testing:
switch(buttonState){
case BUTTON1:
digitalWrite(ledPin, buttonState>0);
break;
case BUTTON2:
digitalWrite(ledPin, buttonState>0);
break;
case BUTTON3:
digitalWrite(ledPin, buttonState>0);
break;
case BUTTON4:
digitalWrite(ledPin, buttonState>0);
break;
case BUTTON5:
digitalWrite(ledPin, buttonState>0);
break;
}
}
can someone please help me to understand this in there are a 10k, 22k, 47k, 68k and a 82k. i do not have most of them resistors value i have 1k, 4.7k 10k, 20k, and i think i got some 15k some place i have to look can someone please help me out? Thank you.
