2-way radio comm.

3 files changed, 51 insertions, 19 deletions

diff --git a/lock/back.c b/lock/back.c
index c5dc35e..9da6688 100644
--- a/lock/back.c
+++ b/lock/back.c
@@ -1,11 +1,14 @@
+/* Door back, connected to the fingerprint scanner */
+
 #include <stdint.h>
-#include <stdlib.h>
 #include <string.h>
+
 #include <avr/interrupt.h>
 #include <util/delay.h>
 
 #include "nrfm.h"
 #include "uart.h"
+#include "util.h"
 
 #define RX_PIN         PD7
 #define RX_DDR         DDRD
@@ -15,15 +18,26 @@
 #define RX_PCMSK       PCMSK2
 #define RX_PCINTVEC    PCINT2_vect
 
-static int rxdr = 0;
+// todo: atomic var
+static volatile int rxdr = 0;
+
+static inline void await_reply(void)
+{
+	uint8_t i;
+
+	radio_listen();
+	for (i = 0; i < 500 && rxdr == 0; i += 100)
+		_delay_ms(100);
+}
 
 int main(void)
 {
-	uint8_t n;
-	char s[2];
-	char buf[MAXPDLEN + 1];
+	uint8_t rxaddr[ADDRLEN] = { 194, 178, 83 };
+	uint8_t txaddr[ADDRLEN] = { 194, 178, 82 };
 
-	uint8_t rxaddr[] = { 194, 178, 83 };
+	char buf[WDLEN + 1];
+	char key[WDLEN + 1];
+	char msg[WDLEN + 1];
 
 	RX_DDR &= ~(1 << RX_PIN);
 	RX_PORT |= (1 << RX_PIN); 
@@ -39,22 +53,36 @@ int main(void)
 
 	for (;;) {
 		if (rxdr) {
-			n = radio_recv(buf, MAXPDLEN);
+			n = radio_recv(buf, WDLEN);
 			buf[n] = '\0';
-			uart_write("Received data: ");
-			uart_write(itoa(n, s, 10));
-			uart_write_line(" bytes");
 			rxdr = 0;
-			if (n > 0) {
-				uart_write("INFO: ");
-				uart_write_line(buf);
+			xor(KEY, buf, msg, WDLEN);
+			if (strncmp(msg, SYN, WDLEN) == 0) {
+				xor(KEY, key, msg, WDLEN);
+				radio_sendto(txaddr, msg, WDLEN);
+				await_reply();
+				if (rxdr) {
+					n = radio_recv(buf, WDLEN);
+					buf[n] = '\0';
+					rxdr = 0;
+					xor(key, buf, msg, WDLEN);
+					if (strncmp(msg, LOCK, WDLEN) == 0) {
+						uart_write_line("LOCKED");
+					} else if (strncmp(msg, UNLOCK, WDLEN) == 0) {
+						uart_write_line("UNLOCKED");
+					} else {
+						uart_write("ERROR: unknown message ");
+						uart_write_line(msg);
+					}
+				}
+			} else {
+				uart_write_line("ERROR: handshake failed");
 			}
 		} else {
 			uart_write_line("No IRQ");
 			_delay_ms(2000);
 		}
 	}
-
 	return 0;
 }
 
diff --git a/lock/frnt.c b/lock/frnt.c
index cef60f3..88ee614 100644
--- a/lock/frnt.c
+++ b/lock/frnt.c
@@ -1,7 +1,8 @@
-/* Door front, connected to the fingerprint scanner  */
+/* Door front, connected to the fingerprint scanner */
 
 #include <stdint.h>
-#include <string.h>
+
+#include <avr/interrupt.h>
 #include <util/delay.h>
 
 #include "nrfm.h"
@@ -21,6 +22,8 @@ static volatile int rxdr = 0;
 
 static inline void await_reply(void)
 {
+	uint8_t i;
+
 	radio_listen();
 	for (i = 0; i < 500 && rxdr == 0; i += 100)
 		_delay_ms(100);
@@ -28,7 +31,6 @@ static inline void await_reply(void)
 
 int main(void)
 {
-	uint8_t i;
 	uint8_t rxaddr[ADDRLEN] = { 194, 178, 82 };
 	uint8_t txaddr[ADDRLEN] = { 194, 178, 83 };
 
@@ -43,6 +45,8 @@ int main(void)
 	radio_init(rxaddr);
 	radio_print_config();
 
+	sei();
+
 	for (;;) {
 		_delay_ms(2000); /* todo: fingerprint check */
 		xor(KEY, SYN, msg, WDLEN);
@@ -53,6 +57,7 @@ int main(void)
 			msg[n] = '\0';
 			rxdr = 0;
 			xor(KEY, msg, key, WDLEN);
+			// check btn press
 			xor(key, LOCK, msg, WDLEN);
 			radio_sendto(txaddr, msg, WDLEN);
 			await_reply();
diff --git a/lock/util.h b/lock/util.h
index 3f6d7a2..64f6ad5 100644
--- a/lock/util.h
+++ b/lock/util.h
@@ -6,8 +6,7 @@
 #define KEY       "dM>}jdb,6gsnC$J^K 8(I5vyPemPs%;K"
 #define SYN       "43iqr5$NB8SpN?Z/52{iVl>o|i!.'dsT"
 #define LOCK      "R,I7l^E4j]KyLR9'*Q{Jd'zu.~!84}Ij"
-#define LOCKED    "R,I7l^E4j]KyLR9'*Q{Jd'zu.~!84}Ik"
-#define UNLOCKED  "R,I7l^E4j]KyLR9'*Q{Jd'zu.~!84}Il"
+#define UNLOCK    "R,I7l^E4j]KyLR9'*Q{Jd'zu.~!84}Ik"
 
 void xor(const char *k, const char *s, char *d, uint8_t n);