X-Git-Url: http://git.droids-corp.org/?p=beacon-rx-433.git;a=blobdiff_plain;f=main.c;h=82f12d7cc28f1233a2ba3b0036670259c5f66a86;hp=35a86cf7de11c84fe90de9eba40665301eea7e71;hb=862393188b1eda01abbb9605e4396d9e06b825fd;hpb=0878ff0726cff2df249e065eebdbd9c35ce9071c

diff --git a/main.c b/main.c
index 35a86cf..82f12d7 100644
--- a/main.c
+++ b/main.c
@@ -27,12 +27,17 @@
 #define RADIO_READ() (!!(PINB & (_BV(RADIO_BIT))))
 
 #define BUTTON_BIT 3
-#define BUTTON_IS_PRESSED()  (!!(PINB & (_BV(BUTTON_BIT))))
+#define BUTTON_IS_PRESSED()  (!(PINB & (_BV(BUTTON_BIT))))
 
 #define LED_BIT    4
 #define LED_ON()   PORTB |= _BV(LED_BIT)
 #define LED_OFF()  PORTB &= (~_BV(LED_BIT))
 
+#define MODE_NO_FILTER     0
+#define MODE_FILTER_THRES1 1
+#define MODE_FILTER_THRES2 2
+#define MODE_MAX           3
+
 static uint32_t bitfield;
 
 #ifdef HOST_VERSION
@@ -344,6 +349,21 @@ static uint8_t get_input(int i)
 #endif
 }
 
+#ifndef HOST_VERSION
+static void beep(void)
+{
+	uint16_t i;
+
+	for (i = 0; i < 1000; i++) {
+		if (i < 250 && (i & 1))
+			BUZZER_ON();
+		else
+			BUZZER_OFF();
+		wait_period();
+	}
+}
+#endif
+
 /*
   The CPU runs at 8Mhz.
   Fe = 5Khz
@@ -354,11 +374,16 @@ static uint8_t get_input(int i)
 int main(void)
 {
 	int8_t detected = 0;
+	uint8_t mode = MODE_FILTER_THRES2;
 	int16_t i;
+#ifndef HOST_VERSION
+	uint8_t button = 0, button_filter = 0;
+#endif
 
 	/* led and buzzer are outputs */
 #if defined(__AVR_ATtiny45__)
 	DDRB |= (1 << LED_BIT) | (1 << BUZZER_BIT);
+	PORTB |= (1 << BUTTON_BIT); /* pull up */
 #endif
 
 	i = 0;
@@ -366,12 +391,42 @@ int main(void)
 
 	while (1) {
 
+		/* wait until 200us is elapsed since previous call (5Khz) */
 		wait_period();
+		detected = 0;
+
+#ifndef HOST_VERSION
+		/* filter button */
+		button = 0;
+		if (BUTTON_IS_PRESSED() && button_filter < 10) {
+			button_filter++;
+			if (button_filter == 10)
+				button = 1;
+		}
+		else if (!BUTTON_IS_PRESSED())
+			button_filter = 0;
+
+		/* change mode if button is pressed */
+		if (button) {
+			uint8_t j;
+
+			mode ++;
+			if (mode >= MODE_MAX)
+				mode = 0;
+
+			for (j = 0; j <= mode; j++)
+				beep();
+
+			/* reset input history */
+			bitfield = 0;
+		}
+#endif
 
 		/* push one bit in bitfield */
 		bitfield <<= 1UL;
 		bitfield |= (uint32_t)get_input(i);
 
+		/* filter the input */
 		apply_filters();
 		mean_pow(&pow_fond, fil_fond);
 		mean_pow(&pow_harm1, fil_harm1);
@@ -386,6 +441,22 @@ int main(void)
 		else if (cpt_filter > 0)
 			cpt_filter--;
 
+		switch (mode) {
+			case MODE_NO_FILTER:
+			case MODE_FILTER_THRES1:
+				/* low threshold, some risk of false positive */
+				if (cpt_filter > 100)
+					detected = 1;
+				break;
+			case MODE_FILTER_THRES2:
+				/* high threshold */
+				if (cpt_filter > 250)
+					detected = 1;
+				break;
+			default:
+				break;
+		}
+
 #ifdef HOST_VERSION
 		/* display values */
 		printf("%d fil_fond=%d fil_harm1=%d fil_other=%d\n",
@@ -399,18 +470,28 @@ int main(void)
 		else
 			LED_OFF();
 
-		/* output a square signal at 625 hz if beacon is
-		 * detected */
-		if ((detected == 1) && (i & 4))
-			BUZZER_ON();
-		else
-			BUZZER_OFF();
-
+		/* if filtering is disabled, just copy the radio input
+		 * on the buzzer */
+		if (mode == MODE_NO_FILTER) {
+			if (RADIO_READ())
+				BUZZER_ON();
+			else
+				BUZZER_OFF();
+		}
+		/* with filtering enabled, output a square signal at
+		 * 625 hz if beacon is detected */
+		else {
+			if ((detected == 1) && (i & 4))
+				BUZZER_ON();
+			else
+				BUZZER_OFF();
+		}
 #endif
 
 		i ++;
 
 #ifdef HOST_VERSION
+		/* exit when all samples are processed */
 		if (i >= sizeof(x))
 			break;
 #endif