linear interpolation, prepare multi TSOP

[aversive.git] / projects / microb2010 / tests / static_beacon / static_beacon.c

diff --git a/projects/microb2010/tests/static_beacon/static_beacon.c b/projects/microb2010/tests/static_beacon/static_beacon.c
index 9f9c8d6..d2accb3 100755 (executable)
--- a/projects/microb2010/tests/static_beacon/static_beacon.c
+++ b/projects/microb2010/tests/static_beacon/static_beacon.c
@@ -24,6 +24,7 @@
 
 #include <aversive.h>
 #include <aversive/wait.h>
+#include <aversive/pgmspace.h>
 
 #include <uart.h>
 
@@ -130,6 +131,7 @@
 #error "speed not defined"
 #endif
 
+extern prog_uint16_t framedist_table[];
 /* basic functions to transmit on IR */
 
 static inline void xmit_0(void)
@@ -216,33 +218,20 @@ static uint16_t do_cksum(uint16_t val)
 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);