Hi
Thank you for your time reading this, I have spent about 3 weeks on this problem and just nothing seems to work, I'm stuck 
I have a little program that uses a Attiny85 and a shift register to light 16 LED's in what will be different patterns.
Everything works perfect without the sleep and interrupt functions but when I use the interrupt with a push button it behaves strangely. The sleep works fine as it should, It wakes up fine but when it awakens I use an int count to move to the next if statement in loop() which checks if the cycle count is more than 1 and then sends it back to 0 which then should put the Attiny85 back into sleep mode..
What happens though is after pressing the push button during the light pattern in cycle 1 it then starts the light pattern again as if it's still at 1 in the cycle even though I have cycle++; in the interrupt which works and adds 1 to move it onto the pattern in the first place but now it won't add anything to cycle with a button press any longer. I can't get my head around how it would be either skipping 0 or somehow it's restarting the same loop where it was put into sleep? It's difficult to tell without serial.println.
Any help would be much appreciated.
Thanks
#include <avr/sleep.h>
#include <avr/interrupt.h>
const int latchPin = 0;
const int clockPin = 1;
const int dataPin = 2;
const int buttonPin = 3;
//Count for stage in cycle of patterns
int cycle = 0;
//Push button debouncer
int buttonState;
int lastButtonState = LOW;
unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 50;
//Count for first pattern of LED's and count for Millis of that pattern
int aCount = 0;
unsigned long pat1preMillis = 0;
void setup() {
pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
pinMode(buttonPin, INPUT);
//Basic flash of LED's to confirm setup, Will be deleted when finished
byte flash1 = B10001000;
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, flash1);
digitalWrite(latchPin, HIGH);
delay(500);
byte flash2 = B01001000;
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, flash2);
digitalWrite(latchPin, HIGH);
delay(500);
byte flash3 = B10001000;
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, flash3);
digitalWrite(latchPin, HIGH);
delay(500);
wipe();
}
void loop() {
unsigned long currentMillis = millis();
int reading = digitalRead(buttonPin);
if (reading != lastButtonState) {
lastDebounceTime = millis();
}
if ((millis() - lastDebounceTime) > debounceDelay) {
if (reading != buttonState) {
buttonState = reading;
if (buttonState == HIGH) {
wipe();
cycle++;
}
}
}
lastButtonState = reading;
if (cycle == 0) {
sleep();
}
else if (cycle == 1) {
byte seq1[16] = {B10001000,B01001000,B00101000,B00011000,
B00010100,B00100100,B01000100,B10000100,
B10000010,B01000010,B00100010,B00010010,
B00010001,B00100001,B01000001,B10000001};
int ledGap = 300;
if (currentMillis - pat1preMillis > ledGap) {
if (aCount < 16) {
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, seq1[aCount]);
digitalWrite(latchPin, HIGH);
aCount++;
}
if (aCount == 16) {
aCount = 0;
}
pat1preMillis = currentMillis;
}
}
else if (cycle > 1) {
cycle = 0;
}
}
//Turn all LED's off and reset pattern counts to 0
void wipe() {
byte pattern = B00000000;
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, pattern);
digitalWrite(latchPin, HIGH);
aCount = 0;
}
//Attiny85 sleep code
void sleep() {
GIMSK |= _BV(PCIE); // Enable Pin Change Interrupts
PCMSK |= _BV(PCINT3); // Use PB3 as interrupt pin
ADCSRA &= ~_BV(ADEN); // ADC off
set_sleep_mode(SLEEP_MODE_PWR_DOWN); // replaces above statement
sleep_enable(); // Sets the Sleep Enable bit in the MCUCR Register (SE BIT)
sei(); // Enable interrupts
sleep_cpu(); // sleep
cli(); // Disable interrupts
PCMSK &= ~_BV(PCINT3); // Turn off PB3 as interrupt pin
sleep_disable(); // Clear SE bit
ADCSRA |= _BV(ADEN); // ADC on
sei();
}
//Attiny85 interrupt code
ISR(PCINT0_vect) {
cycle++;
}