X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=main.c;h=3ad3bec873e61ab7aacf61c69a55b2b2b3e14f83;hb=39a998dd6178bbbdc88611486129581f77daae68;hp=0cae7e6e5e64dcf783e3711e777b9d303ba7b3de;hpb=e8e66d024473bcf0c9e535cc3cb8b71677257687;p=megadrive.git

diff --git a/main.c b/main.c
index 0cae7e6..3ad3bec 100644
--- a/main.c
+++ b/main.c
@@ -22,11 +22,16 @@ static struct {
 		uint8_t fixed_state[4];
 		uint32_t fixed_state32;
 	};
+	union {
+		uint8_t pending_state[4];
+		uint32_t pending_state32;
+	};
 	uint32_t stream_enable_to:1;
 	uint32_t stream_enable_from:1;
 	uint32_t stream_started:1;
 	uint32_t stream_ended:1;
 	uint32_t use_readinc:1;
+	uint32_t use_pending:1;
 	uint32_t frame_cnt;
 	uint32_t edge_cnt;
 	uint32_t t_i;
@@ -53,6 +58,7 @@ void yield(void)
 {
 }
 
+/* portb handles TH */
 static void portb_isr_fixed(void)
 {
 	uint32_t isfr, th;
@@ -128,6 +134,7 @@ static noinline void do_from_step(void)
 
 	// should hopefully give atomic fixed_state read..
 	s = g.fixed_state32;
+	g.fixed_state32 = g.pending_state32;
 	g.stream_from[g.f_i][0] = s;
 	g.stream_from[g.f_i][1] = s >> 8;
 	g.f_i = (g.f_i + 1) & STREAM_BUF_MASK;
@@ -252,6 +259,7 @@ static void do_start_seq(void)
 		}
 	}
 	else if (g.stream_enable_from) {
+		g.use_pending = 1;
 		if (g.use_readinc) {
 			attachInterruptVector(IRQ_PORTB,
 						portb_isr_fixed_do_from);
@@ -262,9 +270,6 @@ static void do_start_seq(void)
 			attachInterruptVector(IRQ_PORTC,
 					      portc_isr_frameinc_do_from);
 		}
-
-		// prep first frame already
-		do_from_step();
 	}
 	__enable_irq();
 }
@@ -274,9 +279,10 @@ static void clear_state(void)
 {
 	g.stream_enable_to = 0;
 	g.stream_enable_from = 0;
-	g.use_readinc = 0;
 	g.stream_started = 0;
 	g.stream_ended = 0;
+	g.use_readinc = 0;
+	g.use_pending = 0;
 	g.t_i = g.t_o = 0;
 	g.f_i = g.f_o = 0;
 	g.frame_cnt = 0;
@@ -302,7 +308,11 @@ static void do_usb(void *buf)
 
 	switch (pkt->type) {
 	case PKT_FIXED_STATE:
-		memcpy(g.fixed_state, pkt->data, sizeof(g.fixed_state));
+		memcpy(&i, pkt->data, sizeof(i));
+		if (g.use_pending)
+			g.pending_state32 = i;
+		else
+			g.fixed_state32 = i;
 		break;
 	case PKT_STREAM_ENABLE:
 		__disable_irq();
@@ -345,10 +355,11 @@ static void do_usb(void *buf)
 
 int main(void)
 {
+	uint32_t led_time = 0;
+	uint32_t scheck_time = 0;
 	uint32_t edge_cnt_last;
 	uint32_t edge_cnt;
 	uint8_t buf[64];
-	int timeout;
 	int ret;
 
 	delay(1000); // wait for usb..
@@ -394,15 +405,21 @@ int main(void)
 	asm("mrs %0, BASEPRI" : "=r"(ret));
 	printf("BASEPRI: %d\n", ret);
 
-	timeout = 1000;
 	edge_cnt_last = g.edge_cnt;
 
 	while (1) {
 		struct tas_pkt pkt;
+		uint32_t now;
 
 		while (g.stream_enable_to && !g.stream_ended
 		  && get_space_to() > sizeof(pkt.data) / STREAM_EL_SZ)
 		{
+			if (g.t_i == g.t_o && g.frame_cnt != 0) {
+				printf("underflow detected\n");
+				g.stream_enable_to = 0;
+				break;
+			}
+
 			pkt.type = PKT_STREAM_REQ;
 			pkt.req.frame = g.frame_cnt;
 
@@ -443,31 +460,43 @@ int main(void)
 			}
 		}
 
-		if (timeout == 1000) {
+		now = millis();
+
+		// start condition check
+		if (now - scheck_time > 1000) {
 			edge_cnt = g.edge_cnt;
 			//printf("e: %d th: %d\n", edge_cnt - edge_cnt_last,
 			//      (GPIOB_PDIR >> CORE_PIN0_BIT) & 1);
-			if (edge_cnt - edge_cnt_last > 10000) {
+			if ((g.stream_enable_to || g.stream_enable_from)
+			    && !g.stream_started
+			    && edge_cnt - edge_cnt_last > 10000)
+			{
 				do_start_seq();
 				edge_cnt = g.edge_cnt;
 			}
 			edge_cnt_last = edge_cnt;
+			scheck_time = now;
 		}
 
-		ret = usb_rawhid_recv(buf, timeout);
-		if (ret == 64) {
-			CORE_PIN13_PORTSET = CORE_PIN13_BITMASK;
-
-			do_usb(buf);
-			timeout = 20;
-		}
-		else if (ret == 0) {
-			CORE_PIN13_PORTCLEAR = CORE_PIN13_BITMASK;
-			timeout = 1000;
+		// led?
+		if (CORE_PIN13_PORTREG & CORE_PIN13_BITMASK) {
+			if ((int)(now - led_time) > 10)
+				CORE_PIN13_PORTCLEAR = CORE_PIN13_BITMASK;
 		}
-		else {
-			printf("usb_rawhid_recv: %d\n", ret);
-			timeout = 1000;
+
+		// something on rawhid?
+		if (usb_rawhid_available() > 0)
+		{
+			ret = usb_rawhid_recv(buf, 20);
+			if (ret == 64) {
+				led_time = millis();
+				CORE_PIN13_PORTSET = CORE_PIN13_BITMASK;
+
+				do_usb(buf);
+			}
+			else {
+				printf("usb_rawhid_recv: %d\n", ret);
+			}
 		}
 	}