#include <aversive.h>
#include <aversive/wait.h>
+#include <aversive/pgmspace.h>
#include <uart.h>
//#define NO_MODULATION
#define WAIT_LASER
-//#define MODUL_455KHZ
+#define MODUL_455KHZ
//#define MODUL_56KHZ
-#define MODUL_38KHZ
+//#define MODUL_38KHZ
//#define SPEED_40RPS
-#define SPEED_10RPS
+#define SPEED_20RPS
+//#define SPEED_10RPS
/* beacon identifier: must be odd, 3 bits */
#define BEACON_ID 0x1
#define FRAME_DATA_SHIFT 3
#if (defined MODUL_455KHZ)
-#define N_PERIODS 10
+#define N_PERIODS 15
#define N_CYCLES_0 17
#define N_CYCLES_1 17
#elif (defined MODUL_56KHZ)
/* FRAME must be odd */
/* #define FRAME 0x0B /\* in little endian 1-1-0-1 *\/ */
/* #define FRAME_LEN 4 */
-#define FRAME 0xAA5B /* in little endian */
+#define FRAME 0x4A5B /* in little endian */
#define FRAME_LEN 16
/* pin returns !0 when nothing, and 0 when laser is on photodiode */
#define MAX_INTER_TIME ((uint16_t)(8000*2)) /* t=8ms dist=10cm */
#define IR_DELAY ((uint16_t)(8000*2))
#define INTER_LASER_TIME 30 /* in ms */
+#elif (defined SPEED_20RPS)
+#define MIN_INTER_TIME ((uint16_t)(40*16)) /* t~=80us dist=350cm */
+#define MAX_INTER_TIME ((uint16_t)(2000*16)) /* t=2ms dist=? >10cm */
+#define IR_DELAY ((uint16_t)(2000*16))
+#define INTER_LASER_TIME 10 /* in ms */
#elif (defined SPEED_40RPS)
#define MIN_INTER_TIME ((uint16_t)(40*16)) /* t~=40us dist=350cm */
#define MAX_INTER_TIME ((uint16_t)(2000*16)) /* t=2ms dist=10cm */
#error "speed not defined"
#endif
+extern prog_uint16_t framedist_table[];
/* basic functions to transmit on IR */
static inline void xmit_0(void)
static uint32_t get_frame(uint16_t laserdiff)
{
uint32_t frame = 0;
- double a, d;
- uint16_t frame_dist;
+ uint16_t frame_dist = 256;
+ uint16_t step, val;
- frame |= ((uint32_t)BEACON_ID << BEACON_ID_SHIFT);
+ /* for calibration, return the time */
+ if (0)
+ return laserdiff;
- /* process angle from laserdiff time */
-#ifdef SPEED_10RPS
- /* timer = 2Mhz */
- a = ((double)laserdiff / (2000000./10.)) * 2. * M_PI;
-#else
- /* timer = 16Mhz */
- a = ((double)laserdiff / (16000000./40.)) * 2. * M_PI;
-#endif
- /* get distance from angle */
- d = LASER_DIST / sin(a/2);
-
- /* scale it between 0 and 511 */
- if (d <= MIN_DIST)
- return 0;
- if (d >= MAX_DIST)
- return 0;
- d -= MIN_DIST;
- d /= (MAX_DIST-MIN_DIST);
- d *= 512;
- frame_dist = (uint16_t)d;
- if (frame_dist >= 512) /* should not happen... */
- return 0;
+ for (step = 128; step != 0; step /= 2) {
+ val = pgm_read_word(&framedist_table[frame_dist]);
+ if (laserdiff > val)
+ frame_dist -= step;
+ else
+ frame_dist += step;
+ }
frame |= ((uint32_t)(frame_dist & FRAME_DATA_MASK) << FRAME_DATA_SHIFT);
uint16_t time1, time2;
uint16_t diff;
-#ifdef SPEED_40RPS
+#if (defined SPEED_40RPS) || (defined SPEED_20RPS)
/* set timer to 16Mhz, we will use ICP */
TCCR1A = 0;
TCCR1B = _BV(CS10);
while (1);
#endif
+#if 0
+ /* test freq ~ 400khz */
+ ICR1 = 38;
+ OCR1A = 19;
+ TCCR1B = _BV(WGM13) | _BV(WGM12);
+ TCNT1 = 37;
+ TCCR1A = _BV(COM1A1) | _BV(WGM11);
+ TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10);
+
+ /* motor PWM 50%, 8khz */
+ DDRB |= 0x08;
+ OCR2 = 50;
+ TCCR2 = _BV(WGM21) | _BV(WGM20) | _BV(COM21) | _BV(CS21) ;
+
+ while (1);
+#endif
+
/* configure timer 0, prescaler = 64 */
TCCR0 = _BV(CS01) | _BV(CS00);