Smart Pet Feeder

1#define F_CPU 8000000UL
2#include <avr/io.h>
3#include <util/delay.h>
4
5// LCD Pins
6#define LCD_RS PD0
7#define LCD_E  PD1
8#define LCD_D4 PD4
9#define LCD_D5 PD5
10#define LCD_D6 PD6
11#define LCD_D7 PB3
12
13// Water system
14#define WATER_SENSOR_PIN  PB5
15#define WATER_PUMP_PIN    PB4
16#define WATER_GREEN_LED   PB7
17#define WATER_RED_LED     PD2
18#define WATER_BUZZER      PC1
19
20// Food system
21#define FOOD_GREEN_LED    PD3
22#define FOOD_RED_LED      PC0
23#define SERVO_PIN         PD7
24
25// HX711
26#define HX711_DT          PA0
27#define HX711_SCK         PC3
28
29// Manual Feed Button
30#define MANUAL_FEED_BTN   PC2
31
32// LCD functions
33void lcd_enable() {
34    PORTD |= (1<<LCD_E);
35    _delay_us(1);
36    PORTD &= ~(1<<LCD_E);
37    _delay_us(100);
38}
39
40void lcd_send_nibble(uint8_t nibble) {
41    if (nibble & (1<<0)) PORTD |= (1<<LCD_D4); else PORTD &= ~(1<<LCD_D4);
42    if (nibble & (1<<1)) PORTD |= (1<<LCD_D5); else PORTD &= ~(1<<LCD_D5);
43    if (nibble & (1<<2)) PORTD |= (1<<LCD_D6); else PORTD &= ~(1<<LCD_D6);
44    if (nibble & (1<<3)) PORTB |= (1<<LCD_D7); else PORTB &= ~(1<<LCD_D7);
45    lcd_enable();
46}
47
48void lcd_send_cmd(uint8_t cmd) {
49    PORTD &= ~(1<<LCD_RS);
50    lcd_send_nibble(cmd >> 4);
51    lcd_send_nibble(cmd & 0x0F);
52    _delay_ms(2);
53}
54
55void lcd_send_data(uint8_t data) {
56    PORTD |= (1<<LCD_RS);
57    lcd_send_nibble(data >> 4);
58    lcd_send_nibble(data & 0x0F);
59    _delay_ms(2);
60}
61
62void lcd_init() {
63    DDRD |= (1<<LCD_RS) | (1<<LCD_E) | (1<<LCD_D4) | (1<<LCD_D5) | (1<<LCD_D6);
64    DDRB |= (1<<LCD_D7);
65    _delay_ms(20);
66
67    lcd_send_nibble(0x03); _delay_ms(5);
68    lcd_send_nibble(0x03); _delay_us(150);
69    lcd_send_nibble(0x03); _delay_ms(5);
70    lcd_send_nibble(0x02); _delay_ms(2);
71
72    lcd_send_cmd(0x28);
73    lcd_send_cmd(0x0C);
74    lcd_send_cmd(0x06);
75    lcd_send_cmd(0x01);
76    _delay_ms(5);
77}
78
79void lcd_clear() {
80    lcd_send_cmd(0x01);
81    _delay_ms(5);
82}
83
84void lcd_gotoxy(uint8_t x, uint8_t y) {
85    lcd_send_cmd(0x80 + (y * 0x40) + x);
86}
87
88void lcd_puts(const char* str) {
89    while(*str) {
90        lcd_send_data(*str++);
91    }
92}
93
94// HX711 Functions
95void HX711_init() {
96    DDRC |= (1<<HX711_SCK);
97    DDRA &= ~(1<<HX711_DT);
98}
99
100long HX711_read() {
101    long count = 0;
102    uint8_t i;
103
104    PORTC &= ~(1<<HX711_SCK);
105    while(PINA & (1<<HX711_DT)); // Wait until DOUT LOW
106
107    for (i=0; i<24; i++) {
108        PORTC |= (1<<HX711_SCK);
109        count = count << 1;
110        PORTC &= ~(1<<HX711_SCK);
111        if (PINA & (1<<HX711_DT)) count++;
112    }
113
114    PORTC |= (1<<HX711_SCK);
115    count ^= 0x800000;
116    PORTC &= ~(1<<HX711_SCK);
117
118    return count;
119}
120
121// Servo PWM
122void Servo_init() {
123    DDRD |= (1<<SERVO_PIN);
124}
125
126void Servo_pulse(uint16_t us) {
127    PORTD |= (1<<SERVO_PIN);
128    while (us--) _delay_us(1);
129    PORTD &= ~(1<<SERVO_PIN);
130    _delay_ms(20);
131}
132
133void Servo_set_angle(uint8_t angle) {
134    uint16_t pulse = 1000 + ((uint32_t)angle * 1000) / 180;
135    for (int i = 0; i < 50; i++) {
136        Servo_pulse(pulse);
137    }
138}
139
140// Initialization
141void init_ports() {
142    // Outputs
143    DDRB |= (1<<WATER_PUMP_PIN) | (1<<WATER_GREEN_LED) | (1<<LCD_D7);
144    DDRD |= (1<<FOOD_GREEN_LED) | (1<<WATER_RED_LED) | (1<<SERVO_PIN) | (1<<LCD_RS) | (1<<LCD_E) | (1<<LCD_D4) | (1<<LCD_D5) | (1<<LCD_D6);
145    DDRC |= (1<<WATER_BUZZER) | (1<<FOOD_RED_LED);
146
147    // Inputs
148    DDRB &= ~(1<<WATER_SENSOR_PIN);
149    DDRC &= ~(1<<MANUAL_FEED_BTN);
150}
151
152// Buzzer simple alert (for LOW condition only)
153void sound_alert() {
154    PORTC |= (1<<WATER_BUZZER);
155    _delay_ms(300);
156    PORTC &= ~(1<<WATER_BUZZER);
157    _delay_ms(300);
158}
159
160// Water Control
161void water_dispense() {
162    if (!(PINB & (1<<WATER_SENSOR_PIN))) {
163        lcd_clear();
164        lcd_gotoxy(0,0);
165        lcd_puts("Water Low!");
166
167        PORTD |= (1<<WATER_RED_LED);
168        PORTB &= ~(1<<WATER_GREEN_LED); // OFF green
169
170        sound_alert(); // Alert once
171
172        PORTB |= (1<<WATER_PUMP_PIN);
173
174        while (!(PINB & (1<<WATER_SENSOR_PIN))) {
175            lcd_gotoxy(0,1);
176            lcd_puts("Filling Water..");
177            _delay_ms(500);
178            sound_alert();  // ?? Keep beeping while low
179        }
180
181        PORTB &= ~(1<<WATER_PUMP_PIN);
182        PORTB |= (1<<WATER_GREEN_LED); // Green ON
183        PORTD &= ~(1<<WATER_RED_LED);  // Red OFF
184
185        lcd_clear();
186        lcd_gotoxy(0,0);
187        lcd_puts("Water Full!");
188        _delay_ms(1000);
189    }
190}
191
192// Food Control
193void food_dispense() {
194    long weight = HX711_read();
195    uint8_t manual = 0;
196
197    // Check if the manual feed button is pressed (low)
198    if (!(PINC & (1<<MANUAL_FEED_BTN))) {
199        _delay_ms(50);
200        if (!(PINC & (1<<MANUAL_FEED_BTN))) {
201            manual = 1;
202        }
203    }
204
205    // Check if food is low or manual feed is pressed
206    if (weight < 10000 || manual) {
207        lcd_clear();
208        lcd_gotoxy(0,0);
209        lcd_puts("Low Food!");
210        lcd_gotoxy(0,1);
211        lcd_puts("Dispensing...");
212
213        // Sound the buzzer when food is low (same as water)
214        sound_alert();
215
216        PORTC |= (1<<FOOD_RED_LED);
217        PORTD &= ~(1<<FOOD_GREEN_LED);
218
219        // Dispense food using servo
220        do {
221            if (!manual) {
222                sound_alert();  // ?? Beep while food low, not manual
223            }
224
225            Servo_set_angle(90);  // Dispense food
226            _delay_ms(1000);
227            Servo_set_angle(0);   // Reset servo position
228            _delay_ms(1000);
229
230            weight = HX711_read(); // Check weight after each dispense action
231        } while (weight < 10000 && !manual); // Repeat until food is full or manual action is done
232
233        PORTD |= (1<<FOOD_GREEN_LED);
234        PORTC &= ~(1<<FOOD_RED_LED);
235
236        lcd_clear();
237        lcd_gotoxy(0,0);
238        lcd_puts("Food Bowl Full");
239        _delay_ms(1000);
240    }
241}
242
243// Main loop
244int main(void)
245{
246    init_ports();
247    lcd_init();
248    HX711_init();
249    Servo_init();
250
251    lcd_clear();
252    lcd_gotoxy(0,0);
253    lcd_puts("Smart Pet Feeder");
254
255    while (1)
256    {
257        water_dispense();   // Check and dispense water
258        food_dispense();    // Check and dispense food
259        _delay_ms(500);
260    }
261}