One buttoned bandit slot machine - int function - c

Question

I'm making one-buttoned bandit slot machine made on 3x 7 segment displays and 3x 74HC595 Shift Registers. Problem is that I want to have some kind of indicator that you won (or you partially won - 2 numbers are the same).
losLiczb(latchPin3, dataPin3, clockPin3, data3, liczba3); // liczba3 = in eg. 4
Serial.println("Wylosowana liczba to"); // "Generated number:"
Serial.println(liczba3); // liczba3 = 0
So, liczba1/liczba2/liczba3 is number which was generated in function losLiczb. Main problem is that liczba1/2/3 have assigned number inside function losLiczb (I can chceck correctness via Serial Read), but outside the number liczba1/2/3 is 0, thus program will always indicate that you won. Here is the whole program if you want (some of comments are in polish and are unnessecary,:
int latchPin1 = 5; //Pin connected to ST_CP of 74HC595
int clockPin1 = 4; //Pin connected to SH_CP of 74HC595
int dataPin1 = 6; //Pin connected to DS of 74HC595
int latchPin2 = 8;
int clockPin2 = 7;
int dataPin2 = 9;
int latchPin3 = 11; //11
int clockPin3 = 12; //12
int dataPin3 = 10; //8
int liczba1;
int liczba2;
int liczba3;
const int buttonPin = 2;
int statusPin = 3;
int buttonState = 0;
//holders for infromation you're going to pass to shifting function
byte data;
byte data1;
byte data2;
byte data3;
byte dataArray[10];
byte animacja[8];
byte dummy[1];
void setup() {
//set pins to output because they are addressed in the main loop
pinMode(latchPin1, OUTPUT);
pinMode(latchPin2, OUTPUT);
pinMode(latchPin3, OUTPUT);
pinMode(statusPin, OUTPUT);
pinMode(buttonPin, INPUT);
Serial.begin(9600);
//Arduino doesn't seem to have a way to write binary straight into the code
//so these values are in HEX. Decimal would have been fine, too.
// 00000000 - trzeba zapisywać w translatorze hex-bin w takiej postaci.
// Kolejno od prawej wartości odpowiadają kropce, a, b , c , d, e , f , g
// dataArray[2] = 0xB6; //11111100 FC
dataArray[0] = 0x7F;
dataArray[1] = 0x0C;
dataArray[2] = 0xB6;
dataArray[3] = 0x9E;
dataArray[4] = 0xCC;
dataArray[5] = 0xDA;
dataArray[6] = 0xFA;
dataArray[7] = 0x0E;
dataArray[8] = 0xFE;
dataArray[9] = 0xDE;
animacja[0] = 0x80; //g
animacja[1] = 0x20; //e
animacja[2] = 0x10; //d
animacja[3] = 0x08; //c
animacja[4] = 0x80; //g
animacja[5] = 0x40; //f
animacja[6] = 0x02; //a
animacja[7] = 0x04; //b
dummy[0] = 0x00;
randomSeed(analogRead(0));
}
void loop() {
buttonState = digitalRead(buttonPin);
if (buttonState == HIGH) {
anim();
} else {
idle();
digitalWrite(statusPin, LOW);
}
}
void idle(){
data = dummy[0];
digitalWrite(latchPin1, 0);
shiftOut(dataPin1, clockPin1, data);
digitalWrite(latchPin1, 1);
digitalWrite(latchPin2, 0);
shiftOut(dataPin2, clockPin2, data);
digitalWrite(latchPin2, 1);
digitalWrite(latchPin3, 0);
shiftOut(dataPin3, clockPin3, data);
digitalWrite(latchPin3, 1);
}
// Funkcja odpowiedzialna za animację
void anim(){
for (int p =0; p < 3; p++){
for (int i = 0; i < 8; i++) {
data = animacja[i];
digitalWrite(latchPin1, 0);
shiftOut(dataPin1, clockPin1, data);
digitalWrite(latchPin2, 0);
shiftOut(dataPin2, clockPin2, data);
digitalWrite(latchPin3, 0);
shiftOut(dataPin3, clockPin3, data);
digitalWrite(latchPin1, 1);
digitalWrite(latchPin2, 1);
digitalWrite(latchPin3, 1);
delay(100);
}
}
losLiczb(latchPin1, dataPin1, clockPin1, data1, liczba1);
Serial.println("Wylosowana liczba to");
Serial.println(liczba1);
for (int p =0; p < 2; p++){
for (int i = 0; i < 8; i++) {
data = animacja[i];
digitalWrite(latchPin2, 0);
shiftOut(dataPin2, clockPin2, data);
digitalWrite(latchPin3, 0);
shiftOut(dataPin3, clockPin3, data);
digitalWrite(latchPin2, 1);
digitalWrite(latchPin3, 1);
delay(100);
}
}
losLiczb(latchPin2, dataPin2, clockPin2, data2, liczba2);
Serial.println("Wylosowana liczba to");
Serial.println(liczba2);
for (int p =0; p < 2; p++){
for (int i = 0; i < 8; i++) {
data = animacja[i];
digitalWrite(latchPin3, 0);
shiftOut(dataPin3, clockPin3, data);
digitalWrite(latchPin3, 1);
delay(100);
}
}
losLiczb(latchPin3, dataPin3, clockPin3, data3, liczba3);
Serial.println("Wylosowana liczba to");
Serial.println(liczba3);
if (data1 == data2){
digitalWrite(statusPin, HIGH);
} else {
digitalWrite(statusPin, LOW);
}
delay(5000);
}
//Funckja odpowiedzialna za wylosowanie liczby
int losLiczb(int myLatchPin, int myDataPin, int myClockPin, int myData, int myLiczba) {
//load the light sequence you want from array
int j = random(0, 9);
myLiczba = j;
myData = dataArray[j];
//ground latchPin and hold low for as long as you are transmitting
digitalWrite(myLatchPin, 0);
//move 'em out
shiftOut(myDataPin, myClockPin, myData);
//return the latch pin high to signal chip that it
//no longer needs to listen for information
digitalWrite(myLatchPin, 1);
Serial.println("Wylosowana liczba to");
Serial.println(myLiczba);
}
// the heart of the program
void shiftOut(int myDataPin, int myClockPin, byte myDataOut) {
// This shifts 8 bits out MSB first,
//on the rising edge of the clock,
//clock idles low
//internal function setup
int i=0;
int pinState;
pinMode(myClockPin, OUTPUT);
pinMode(myDataPin, OUTPUT);
//clear everything out just in case to
//prepare shift register for bit shifting
digitalWrite(myDataPin, 0);
digitalWrite(myClockPin, 0);
//for each bit in the byte myDataOut�
//NOTICE THAT WE ARE COUNTING DOWN in our for loop
//This means that %00000001 or "1" will go through such
//that it will be pin Q0 that lights.
for (i=7; i>=0; i--) {
digitalWrite(myClockPin, 0);
//if the value passed to myDataOut and a bitmask result
// true then... so if we are at i=6 and our value is
// %11010100 it would the code compares it to %01000000
// and proceeds to set pinState to 1.
if ( myDataOut & (1<<i) ) {
pinState= 1;
}
else {
pinState= 0;
}
//Sets the pin to HIGH or LOW depending on pinState
digitalWrite(myDataPin, pinState);
//register shifts bits on upstroke of clock pin
digitalWrite(myClockPin, 1);
//zero the data pin after shift to prevent bleed through
digitalWrite(myDataPin, 0);
}
//stop shifting
digitalWrite(myClockPin, 0);
}

Answer 1

Pass the values you want the function to output by reference or by pointer.
void Wrong(int a) {
a = 10;
}
void Right(int& a) {
a = 20;
}
void Right(int* pA) {
*pA = 30;
}
int a = 0;
Wrong(a); printf("%d ", a);
Right(a); printf("%d ", a);
Right(&a); printf("%d\n", a);
output will be 0 20 30