2 * Copyright Droids Corporation (2009)
3 * Olivier Matz <zer0@droids-corp.org>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 * Revision : $Id: main.c,v 1.8 2009-05-02 10:08:09 zer0 Exp $
24 #include <aversive/wait.h>
35 /* beacon identifier: must be odd, 3 bits */
36 #define BEACON_ID_MASK 0x7
37 #define BEACON_ID_SHIFT 0
38 #define FRAME_DATA_MASK 0xFFF8
39 #define FRAME_DATA_SHIFT 3
41 /******************* TSOP */
43 #define EICRx_TSOP EICRB /* EICRA is not ok, cannot do intr on any edge */
45 #define INTx_TSOP INT6
46 #define ISCx0_TSOP ISC60
47 #define ISCx1_TSOP ISC61
48 #define SIG_TSOP SIG_INTERRUPT6
49 #define TSOP_READ() (!(PINE & 0x40))
51 #define INTx_TSOP INT4
52 #define ISCx0_TSOP ISC40
53 #define ISCx1_TSOP ISC41
54 #define SIG_TSOP SIG_INTERRUPT4
55 #define TSOP_READ() (!(PINE & 0x10))
58 //#define MODUL_455KHZ
61 #if (defined MODUL_455KHZ)
62 #define TSOP_FREQ_MHZ 0.455
65 #define TSOP_FREQ_MHZ 0.038
69 #define TSOP_PERIOD_US (1./TSOP_FREQ_MHZ)
71 #define TSOP_TIME_SHORT_US (1.5 * N_PERIODS * TSOP_PERIOD_US)
72 #define TSOP_TIME_LONG_US (2.5 * N_PERIODS * TSOP_PERIOD_US)
74 #define TSOP_TIME_SHORT ((uint16_t)(TSOP_TIME_SHORT_US*2))
75 #define TSOP_TIME_LONG ((uint16_t)(TSOP_TIME_LONG_US*2))
78 #define FRAME_MASK ((1UL << FRAME_LEN) - 1)
81 static uint16_t start_angle_time;
82 static uint16_t frame;
87 struct detected_frame {
92 #define FRAME_RING_ORDER 4
93 #define FRAME_RING_SIZE (1<<FRAME_RING_ORDER)
94 #define FRAME_RING_MASK (FRAME_RING_SIZE-1)
95 static uint8_t frame_ring_head = 0;
96 static uint8_t frame_ring_tail = 0;
97 static struct detected_frame frame_ring[FRAME_RING_SIZE];
99 /********************** CS */
101 /* 8ms, easier if it's a pow of 2 */
102 #define CS_PERIOD_US (8192)
103 #define CS_PERIOD ((uint16_t)(CS_PERIOD_US*2))
104 #define CPT_ICR_MAX (uint8_t)((1000000UL/(uint32_t)CS_PERIOD_US)) /* too slow = 1 tr/s */
105 #define CPT_ICR_MIN (uint8_t)((10000UL/(uint32_t)CS_PERIOD_US)) /* too fast = 100 tr/s */
108 #define CS_CONSIGN (25 * 1000L)
111 * - clear on timer compare (CTC)
112 * - Toggle OC0 on compare match
114 #define LASER_ON() do { TCCR0 = _BV(WGM01) | _BV(COM00) | _BV(CS00); } while (0)
115 #define LASER_OFF() do { TCCR0 = 0; } while (0)
117 struct beacon_tsop beacon_tsop;
119 void debug_serial(void)
124 c = uart_recv_nowait(0);
126 printf("%c", (char)(c+1));
135 void debug_tsop(void)
150 /* val is 16 bits, including 4 bits-cksum in MSB, return 0xFFFF is
151 * cksum is wrong, or the 12 bits value on success. */
152 static uint16_t verify_cksum(uint16_t val)
157 /* add the four 4-bits blocks of val together */
161 cksum = (cksum & 0xf) + ((cksum & 0xf0) >> 4);
164 cksum = (cksum & 0xf) + ((cksum & 0xf0) >> 4);
167 cksum = (cksum & 0xf) + ((cksum & 0xf0) >> 4);
170 return 0xffff; /* wrong cksum */
176 static uint8_t led_cpt = 0;
179 static uint8_t prev_tsop = 0;
183 static uint16_t prev_time;
190 cur_tsop = TSOP_READ();
191 diff_time = cur_time - prev_time;
198 /* first rising edge */
199 if (len == 0 && cur_tsop && diff_time > TSOP_TIME_LONG) {
203 start_angle_time = cur_time - ref_time;
207 else if (len != 0 && diff_time < TSOP_TIME_SHORT) {
216 else if (len != 0 && diff_time < TSOP_TIME_LONG) {
223 /* error case, reset */
229 if (len == FRAME_LEN*2) {
230 uint8_t tail_next = (frame_ring_tail+1) & FRAME_RING_MASK;
231 if (tail_next != frame_ring_head) {
232 frame_ring[frame_ring_tail].frame = (frame & FRAME_MASK);
233 frame_ring[frame_ring_tail].time = start_angle_time;
234 frame_ring_tail = tail_next;
236 if ((led_cpt & 0x7) == 0)
241 prev_time = cur_time;
242 prev_tsop = cur_tsop;
246 static inline int32_t AbS(int32_t x)
254 /* Get the speed of motor (tr / 1000s)
255 * - icr_cpt is the number of CS period between 2 ICR updates
256 * - icr_diff is the difference of ICR values between the ICR updates
257 * (modulo 65536 obviously) */
258 static inline int32_t get_speed(uint8_t icr_cpt, uint16_t icr_diff)
260 int32_t best_diff = 65536L;
261 int8_t best_cpt = -2;
265 /* too slow (less than 1 tr/s) */
266 if (icr_cpt > CPT_ICR_MAX)
269 /* too fast (more than 100 tr/s) */
270 if (icr_cpt < CPT_ICR_MIN)
273 /* try to get the real time knowning icr_cpt and icr_diff */
274 for (i=-1; i<2; i++) {
275 diff = ((icr_cpt+i)&3) * 16384L;
276 diff += (icr_diff & 0x3fff);
283 if (AbS(diff) < AbS(best_diff)) {
285 best_cpt = icr_cpt + i;
289 /* real time difference in 1/2 us */
290 diff = (best_cpt * 16384L) + (icr_diff & 0x3fff);
291 return 2000000000L/diff;
296 uint16_t prev_cs = 0;
297 uint16_t prev_icr = 0;
299 uint16_t diff_icr = 0;
302 int32_t speed, out, err;
307 LED1_DDR |= _BV(LED1_BIT);
308 LED2_DDR |= _BV(LED2_BIT);
309 LED3_DDR |= _BV(LED3_BIT);
310 DDRB |= 0x10; /* OC0 (laser pwm) */
313 pid_init(&beacon_tsop.pid);
314 pid_set_gains(&beacon_tsop.pid, 500, 0, 0);
315 pid_set_maximums(&beacon_tsop.pid, 0, 20000, 4095);
316 pid_set_out_shift(&beacon_tsop.pid, 10);
317 pid_set_derivate_filter(&beacon_tsop.pid, 4);
320 fdevopen(uart0_dev_send, uart0_dev_recv);
322 rdline_init(&beacon_tsop.rdl, write_char, valid_buffer, complete_buffer);
323 snprintf(beacon_tsop.prompt, sizeof(beacon_tsop.prompt), "beacon > ");
324 rdline_newline(&beacon_tsop.rdl, beacon_tsop.prompt);
329 /* configure external interrupt for TSOP */
330 EICRx_TSOP |= _BV(ISCx0_TSOP);
331 EIMSK |= _BV(INTx_TSOP);
334 PWM_NG_TIMER_16BITS_INIT(1, TIMER_16_MODE_PWM_10,
335 TIMER1_PRESCALER_DIV_1);
336 PWM_NG_INIT16(&beacon_tsop.pwm_motor, 1, A, 10, 0, NULL, 0);
339 * - clear on timer compare (CTC)
340 * - Toggle OC0 on compare match
342 TCCR0 = _BV(WGM01) | _BV(COM00) | _BV(CS00);
343 OCR0 = 80; /* f = 100 khz at 16 Mhz */
345 /* configure timer 3: CLK/8
346 * it is used as a reference time
347 * enable noise canceller for ICP3 */
348 TCCR3B = _BV(ICNC3) | _BV(CS11);
352 /* Control system will be done in main loop */
355 /* process pending bytes on uart */
358 /* monitor the value of ICR (which is modified
359 * automatically on TT rising edge). If the value
360 * changed, process the time difference. */
361 if (ETIFR & _BV(ICF3)) {
368 diff_icr = (icr - prev_icr);
372 speed = get_speed(cpt_icr, diff_icr);
375 /* read time reference */
381 if (tcnt3 - prev_cs < CS_PERIOD)
391 /* process CS... maybe we don't need to use
392 * control_system_manager, just PID is enough */
393 if (cpt == CPT_ICR_MAX)
396 speed = get_speed(cpt_icr, diff_icr);
398 /* enabled laser when rotation speed if at least 5tr/s */
404 err = CS_CONSIGN - speed;
405 out = pid_do_filter(&beacon_tsop.pid, err);
406 if (x == 0 && beacon_tsop.debug_speed)
407 printf("%ld %ld\n", speed, out);
414 pwm_ng_set(&beacon_tsop.pwm_motor, out);
418 /* count the number of CS period between 2 ICR
420 if (cpt < CPT_ICR_MAX)
423 /* after CS, check if we have a new frame in ring */
424 if (frame_ring_head != frame_ring_tail) {
427 head_next = (frame_ring_head+1) & FRAME_RING_MASK;
428 frame = frame_ring[frame_ring_head].frame;
430 /* display if needed */
431 if (beacon_tsop.debug_frame) {
435 beacon_id = (frame >> BEACON_ID_SHIFT) & BEACON_ID_MASK;
436 data = (frame >> FRAME_DATA_SHIFT) & FRAME_DATA_MASK;
437 printf("ID=%d data=%d time=%d\r\n",
439 frame_ring[frame_ring_head].time);
441 frame_ring_head = head_next;