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)
10 #define MEASUREMENT_SHIFT 2 // running avg (1 << M_SHIFT)
14 #define N_TRIG_SENSORS 4
16 // static int16_t distances[N_SENSORS];
18 // hold_regs[0] is unit ID
19 #define thresholds (hold_regs+1)
20 #define led1_sensors (hold_regs[13])
21 #define led2_sensors (hold_regs[14])
23 #define led_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM])
24 #define distances (hold_regs+MB_N_HOLD_REGS_EEPROM+1)
25 #define free_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM+13])
26 #define err_bitmap (hold_regs[MB_N_HOLD_REGS_EEPROM+14])
28 static void pull_trigger(uint8_t trig)
31 case 0: PORTD |= _BV(PD7); _delay_us(10); PORTD &= ~_BV(PD7); break;
32 case 1: PORTB |= _BV(PB4); _delay_us(10); PORTB &= ~_BV(PB4); break;
33 case 2: PORTC |= _BV(PC4); _delay_us(10); PORTC &= ~_BV(PC4); break;
37 static uint16_t get_pin(uint8_t trig)
40 case 0: return (PIND & 0x78) >> 3;
41 case 1: return PINB & 0x0F;
42 default: return PINC & 0x0F;
46 static void do_measurement(unsigned char trig)
48 uint16_t starttimes[N_TRIG_SENSORS], starttime;
49 uint8_t to_start = (1 << N_TRIG_SENSORS) - 1;
50 uint8_t to_measure = 0, i;
54 starttime = get_clock();
56 while (to_start || to_measure) {
58 uint16_t now = get_clock();
60 if (now-starttime >= ECHO_TIMEOUT)
65 for (i = 0; i < N_TRIG_SENSORS; i++) {
66 uint8_t mask = 1 << i;
68 if ((to_start & mask) && (bits & mask)) {
73 } else if ((to_measure & mask) && !(bits & mask)) {
74 uint16_t old_d, new_d;
75 uint8_t idx = trig*N_TRIG_SENSORS+i;
78 new_d = now - starttimes[i];
79 old_d = distances[idx];
83 distances[idx] = new_d;
86 (old_d << MEASUREMENT_SHIFT)
89 ) >> MEASUREMENT_SHIFT;
95 for (i = 0; i < N_TRIG_SENSORS; i++)
96 if (to_start & (1 << i))
97 distances[trig*N_TRIG_SENSORS + i] = -1;
98 else if (to_measure & (1 << i))
99 distances[trig*N_TRIG_SENSORS + i] = 0;
102 static void led_set(uint8_t led, uint8_t state)
135 static void leds_update()
137 if (led_bitmap & 1) {
143 if (led_bitmap & 2) {
149 if (led_bitmap & 4) {
155 if (led_bitmap & 8) {
162 static void eval_bitmaps()
164 uint16_t free_b = 0, err_b = 0, mask;
167 for (i = 0; i < N_SENSORS; i++) {
171 if (distances[i] == -1 || distances[i] == 0) {
173 } else if (distances[i] > thresholds[i]) {
179 free_bitmap = free_b;
183 if (led1_sensors & err_bitmap) {
185 } else if (led1_sensors & free_bitmap) {
193 if (led2_sensors & err_bitmap) {
195 } else if (led2_sensors & free_bitmap) {
203 uint8_t hold_reg_is_valid(uint16_t reg, uint16_t val)
205 if (reg == MB_HOLD_REGS_BASE)
206 return val > 0 && val <= 247;
216 DDRD |= _BV(PD7); // Trig D
217 DDRB |= _BV(PB4) | _BV(PB5); // Trig B, LED 2
218 DDRC |= _BV(PC4) | _BV(PC5); // Trig C, LED 1
222 TCCR1B = _BV(CS12)|_BV(CS10); // CLK/1024
229 for (trig = 0; trig < N_TRIGGERS; trig++) {
231 do_measurement(trig);
233 while (get_clock()-now < MEASUREMENT_WAIT)
238 leds_update(); // might be written from modbus
240 // distances[4] > 100 || distances[11] > 100);