main.c - avr-task-scheduler - AVR mcu bare metal task scheduler

src/main.c (1660B)
Line numbers
   1 #include <avr/io.h>
   2 #include <stddef.h>
   3 
   4 #include "millis.h"
   5 #include "scheduler.h"
   6 
   7 #define BTN_A_PIN 2
   8 #define BTN_B_PIN 3
   9 #define LED_1_PIN 4
  10 #define LED_2_PIN 5
  11 #define LED_3_PIN 6
  12 #define LED_4_PIN 7
  13 
  14 void toggle_led_1(void);
  15 void toggle_led_2(void);
  16 void read_button_a(void);
  17 void read_button_b(void);
  18 
  19 typedef enum {
  20     TOGGLE_LED_1_ID,
  21     TOGGLE_LED_2_ID,
  22     READ_BTN_A_ID,
  23     READ_BTN_B_ID,
  24     TASKS_COUNT
  25 } task_id_e;
  26 
  27 task_t tasks[] = {
  28     //   on_update  period                id
  29     { toggle_led_1,   1000,  TOGGLE_LED_1_ID },
  30     { toggle_led_2,    500,  TOGGLE_LED_2_ID },
  31     { read_button_a,     0,    READ_BTN_A_ID },
  32     { read_button_b,     0,    READ_BTN_B_ID }
  33 };
  34 
  35 void io_setup(void) {
  36     // outputs
  37     DDRD |= (1<<LED_1_PIN) | (1<<LED_2_PIN) | (1<<LED_3_PIN) | (1<<LED_4_PIN);
  38 
  39     // inputs with internall pullup
  40     DDRD &= ~((1<<BTN_A_PIN) | (1<<BTN_B_PIN));
  41     PORTD |= (1<<BTN_A_PIN) | (1<<BTN_B_PIN);
  42 }
  43 
  44 int main(void) {
  45     io_setup();
  46 
  47     millis_init(&scheduler_tick);
  48 
  49     scheduler_init(tasks, sizeof(tasks)/sizeof(tasks[0]));
  50 
  51     while(1) {
  52         scheduler_update();
  53     }
  54 
  55     return 0;
  56 }
  57 
  58 void toggle_led_1(void) {
  59     PIND = (1 << LED_1_PIN);
  60 }
  61 
  62 void toggle_led_2(void) {
  63     PIND = (1 << LED_2_PIN);
  64 }
  65 
  66 void read_button_a(void) {
  67     if (PIND & (1<<BTN_A_PIN)) {
  68         PORTD &= ~(1<<LED_4_PIN);
  69         scheduler_set_task_period(READ_BTN_A_ID, 0);
  70     } else {
  71         PORTD |= (1<<LED_4_PIN);
  72         scheduler_set_task_period(READ_BTN_A_ID, 150);
  73     }
  74 }
  75 
  76 void read_button_b(void) {
  77     if (PIND & (1<<BTN_B_PIN)) {
  78         PORTD &= ~(1<<LED_3_PIN);
  79     } else {
  80         PORTD |= (1<<LED_3_PIN);
  81     }
  82 }