2 #include <avr/interrupt.h>
3 #include <util/delay.h>
8 #define ECHO_TIMEOUT (CLOCK_HZ/20) // 50 ms
9 #define MEASUREMENT_WAIT (4*ECHO_TIMEOUT)
13 #define N_TRIG_SENSORS 4
15 // static int16_t distances[N_SENSORS];
17 // hold_regs[0] is unit ID
18 #define thresholds (hold_regs+1)
19 #define led1_sensors (hold_regs[13])
20 #define led2_sensors (hold_regs[14])
22 #define led_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM])
23 #define distances (hold_regs+MB_N_HOLD_REGS_EEPROM+1)
24 #define free_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM+13])
25 #define err_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM+14])
27 static void pull_trigger(uint8_t trig)
30 case 0: PORTD |= _BV(PD7); _delay_us(10); PORTD &= ~_BV(PD7); break;
31 case 1: PORTB |= _BV(PB4); _delay_us(10); PORTB &= ~_BV(PB4); break;
32 case 2: PORTC |= _BV(PC4); _delay_us(10); PORTC &= ~_BV(PC4); break;
36 static uint16_t get_pin(uint8_t trig)
39 case 0: return (PIND & 0x78) >> 3;
40 case 1: return PINB & 0x0F;
41 default: return PINC & 0x0F;
45 static void do_measurement(unsigned char trig)
47 uint16_t starttimes[N_TRIG_SENSORS], starttime;
48 uint8_t to_start = (1 << N_TRIG_SENSORS) - 1;
49 uint8_t to_measure = 0, i;
53 starttime = get_clock();
55 while (to_start || to_measure) {
57 uint16_t now = get_clock();
59 if (now-starttime >= ECHO_TIMEOUT)
64 for (i = 0; i < N_TRIG_SENSORS; i++) {
65 uint8_t mask = 1 << i;
67 if ((to_start & mask) && (bits & mask)) {
72 } else if ((to_measure & mask) && !(bits & mask)) {
75 distances[trig*N_TRIG_SENSORS + i]
76 = now - starttimes[i];
81 for (i = 0; i < N_TRIG_SENSORS; i++)
82 if (to_start & (1 << i))
83 distances[trig*N_TRIG_SENSORS + i] = -1;
84 else if (to_measure & (1 << i))
85 distances[trig*N_TRIG_SENSORS + i] = 0;
88 static void led_set(uint8_t led, uint8_t state)
121 static void leds_update()
123 if (led_bitmap & 1) {
129 if (led_bitmap & 2) {
135 if (led_bitmap & 4) {
141 if (led_bitmap & 8) {
148 static void eval_bitmaps()
150 uint16_t free_b = 0, err_b = 0, mask;
153 for (i = 0; i < N_SENSORS; i++) {
157 if (distances[i] == -1 || distances[i] == 0) {
159 } else if (distances[i] > thresholds[i]) {
165 free_bitmap = free_b;
169 if (led1_sensors & err_bitmap) {
171 } else if (led1_sensors & free_bitmap) {
179 if (led2_sensors & err_bitmap) {
181 } else if (led2_sensors & free_bitmap) {
189 uint8_t hold_reg_is_valid(uint16_t reg, uint16_t val)
191 if (reg == MB_HOLD_REGS_BASE)
192 return val > 0 && val <= 247;
202 DDRD |= _BV(PD7); // Trig D
203 DDRB |= _BV(PB4) | _BV(PB5); // Trig B, LED 2
204 DDRC |= _BV(PC4) | _BV(PC5); // Trig C, LED 1
208 TCCR1B = _BV(CS12)|_BV(CS10); // CLK/1024
215 for (trig = 0; trig < N_TRIGGERS; trig++) {
217 do_measurement(trig);
219 while (get_clock()-now < MEASUREMENT_WAIT)
224 leds_update(); // might be written from modbus
226 // distances[4] > 100 || distances[11] > 100);