X-Git-Url: https://defiant.homedns.org/gitweb/?p=ros_wild_thumper.git;a=blobdiff_plain;f=avr%2Fnano%2Fmain.c;h=5418055daaf734023e65215f000ce8156d064300;hp=0cb0acfba471aaaf79d67feba98932da429af36c;hb=b039f1fc2f0d99f315139b441b49cc5386da1459;hpb=ddf4584adbff050304f201a528f25c633e10c79d

diff --git a/avr/nano/main.c b/avr/nano/main.c
index 0cb0acf..5418055 100644
--- a/avr/nano/main.c
+++ b/avr/nano/main.c
@@ -4,6 +4,7 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
 #include <avr/sleep.h>
+#include <util/delay.h>
 #include "uart.h"
 
 /*
@@ -13,6 +14,10 @@
  * 0x02 Distance left LSB
  * 0x03 Distance right MSB
  * 0x04 Distance right LSB
+ * 0x05 Distance forward MSB
+ * 0x06 Distance forward LSB
+ * 0x07 Distance backward MSB
+ * 0x08 Distance backward LSB
  *
  * 0xff Bootloader
  */
@@ -26,6 +31,10 @@ static volatile uint8_t ireg=0;
 static volatile uint8_t bootloader=0;
 static volatile uint16_t dist_left=0;
 static volatile uint16_t dist_right=0;
+static volatile uint16_t dist_forward=0;
+static volatile uint16_t dist_backward=0;
+static volatile uint8_t start_dist_fwd=0;
+static volatile uint8_t start_dist_bwd=0;
 
 ISR(TWI_vect)
 {
@@ -41,6 +50,10 @@ ISR(TWI_vect)
 			switch(ireg) {
 				case 0x00: // register select
 					ireg = TWDR;
+
+					if (ireg == 0x05) start_dist_fwd=1;
+					if (ireg == 0x07) start_dist_bwd=1;
+
 					ireg--; // because we do ireg++ below
 					TWI_ACK;
 					break;
@@ -72,6 +85,24 @@ ISR(TWI_vect)
 					TWDR = tmp16;
 					TWI_ACK;
 					break;
+				case 0x05: // Distance forward MSB
+					tmp16 = dist_forward;
+					TWDR = tmp16>>8;
+					TWI_ACK;
+					break;
+				case 0x06: // Distance forward LSB
+					TWDR = tmp16;
+					TWI_ACK;
+					break;
+				case 0x07: // Distance backward MSB
+					tmp16 = dist_backward;
+					TWDR = tmp16>>8;
+					TWI_ACK;
+					break;
+				case 0x08: // Distance backward LSB
+					TWDR = tmp16;
+					TWI_ACK;
+					break;
 				default:
 					TWDR = 0;
 					TWI_NAK;
@@ -128,6 +159,40 @@ static unsigned short get_distance(uint8_t i) {
 }
 
 
+ISR(INT0_vect) {
+	static uint16_t t_start=0;
+	uint16_t t_now = TCNT1;
+	uint16_t t_diff;
+
+	if (bit_is_set(PIND, 2)) { // high level
+		// start timer
+		t_start = t_now;
+	} else {
+		t_diff = t_now - t_start;
+		dist_forward = t_diff*2.7586 + 0.5; // t [µs] / 580 = mm
+		// disable this interrupt
+		EIMSK |= (1 << INT0);
+	}
+}
+
+
+ISR(INT1_vect) {
+	static uint16_t t_start=0;
+	uint16_t t_now = TCNT1;
+	uint16_t t_diff;
+
+	if (bit_is_set(PIND, 3)) { // high level
+		// start timer
+		t_start = t_now;
+	} else {
+		t_diff = t_now - t_start;
+		dist_backward = t_diff*2.7586 + 0.5; // t [µs] / 580 = mm
+		// disable this interrupt
+		EIMSK |= (1 << INT1);
+	}
+}
+
+
 int main(void) {
 	bootloader = 0x00;
 	setup_uart(9600);
@@ -137,16 +202,23 @@ int main(void) {
 	TWAR = 0x52;
 	TWI_RESET;
 
+	// Timer 1: Normal mode, Top: 0xffff, Prescaler: F_CPU/256=62500Hz
+	TCCR1A = 0x0;
+	TCCR1B = (1 << CS12);
+
+	// External Interrupts
+	EICRA = (1 << ISC10) | (1 << ISC00);
+
 	printf("\r\nStart\r\n");
 
 	set_sleep_mode(SLEEP_MODE_IDLE);
 	sei();
 	while(1) {
 		switch(ireg) {
-			case 1: // ir left
+			case 0x01: // ir left
 				dist_left = get_distance(0);
 				break;
-			case 3: // ir right
+			case 0x03: // ir right
 				dist_right = get_distance(1);
 				break;
 			case 0xff: // Magic reg that starts the bootloader
@@ -160,6 +232,31 @@ int main(void) {
 				break;
 		}
 
+		if (start_dist_fwd) {
+			start_dist_fwd = 0;
+			dist_forward = 0;
+
+			DDRD |= (1 << 2);
+			PORTD |= (1 << 2);
+			_delay_us(10);
+			PORTD &= ~(1 << 2);
+			DDRD &= ~(1 << 2);
+			// wait for interrupt
+			EIMSK |= (1 << INT0);
+		}
+		if (start_dist_bwd) {
+			start_dist_bwd = 0;
+			dist_backward = 0;
+
+			DDRD |= (1 << 3);
+			PORTD |= (1 << 3);
+			_delay_us(10);
+			PORTD &= ~(1 << 3);
+			DDRD &= ~(1 << 3);
+			// wait for interrupt
+			EIMSK |= (1 << INT1);
+		}
+
 		sleep_mode();
 	}