[megadrive.git] / main.c

/*
 * TeensyTAS, TAS input player for MegaDrive
 * Copyright (c) 2014 notaz
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "teensy3/core_pins.h"
#include "teensy3/usb_seremu.h"
#include "teensy3/usb_rawhid.h"
#include "pkts.h"

#define noinline __attribute__((noinline))

// use power of 2
#define STREAM_BUF_SIZE 512
#define STREAM_BUF_MASK (512 - 1)

/* ?0SA 00DU, ?1CB RLDU */
#define STREAM_EL_SZ 2

static struct {
	uint8_t stream_to[STREAM_BUF_SIZE][STREAM_EL_SZ];
	uint8_t stream_from[STREAM_BUF_SIZE][STREAM_EL_SZ];
	union {
		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;
	uint32_t t_o;
	uint32_t f_i;
	uint32_t f_o;
} g;

ssize_t _write(int fd, const void *buf, size_t nbyte)
{
	char tbuf[64];
	int ret;

	if (fd != 1 && fd != 2) {
		snprintf(tbuf, sizeof(tbuf), "write to fd %d\n", fd);
		usb_seremu_write(tbuf, strlen(tbuf));
	}

	ret = usb_seremu_write(buf, nbyte);
	return ret < 0 ? ret : nbyte;
}

void yield(void)
{
}

/* portb handles TH */
static void portb_isr_fixed(void)
{
	uint32_t isfr, th;

	isfr = PORTB_ISFR;
	PORTB_ISFR = isfr;
	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;

	GPIOD_PDOR = g.fixed_state[th];
	g.edge_cnt++;
}

static void portb_isr_do_to_inc(void)
{
	uint32_t isfr, th;

	isfr = PORTB_ISFR;
	PORTB_ISFR = isfr;
	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;

	GPIOD_PDOR = g.stream_to[g.t_o][th];
	if (th) {
		g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
		if (g.t_o == g.t_i)
			// done
			attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
		g.frame_cnt++;
	}
	g.edge_cnt++;
}

static void portb_isr_do_to(void)
{
	uint32_t isfr, th;

	isfr = PORTB_ISFR;
	PORTB_ISFR = isfr;
	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;

	GPIOD_PDOR = g.stream_to[g.t_o][th];
	g.edge_cnt++;
}

static void portc_isr_nop(void)
{
	uint32_t isfr;

	isfr = PORTC_ISFR;
	PORTC_ISFR = isfr;
}

// /vsync starts at line 235/259 (ntsc/pal), just as vcounter jumps back
// we care when it comes out (/vsync goes high) after 3 lines at 238/262
static void portc_isr_frameinc(void)
{
	uint32_t isfr;

	isfr = PORTC_ISFR;
	PORTC_ISFR = isfr;

	g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
	if (g.t_o == g.t_i) {
		attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
		attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	}
	g.frame_cnt++;
}

/* "recording" data */
static noinline void do_from_step(void)
{
	uint32_t s;

	// 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;
}

static void portb_isr_fixed_do_from(void)
{
	uint32_t isfr, th;

	isfr = PORTB_ISFR;
	PORTB_ISFR = isfr;
	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;

	GPIOD_PDOR = g.fixed_state[th];
	if (th)
		do_from_step();
	g.edge_cnt++;
}

static void portc_isr_frameinc_do_from(void)
{
	uint32_t isfr;

	isfr = PORTC_ISFR;
	PORTC_ISFR = isfr;

	do_from_step();
	g.frame_cnt++;
}

static void udelay(uint32_t us)
{
	uint32_t start = micros();

	while ((micros() - start) < us) {
		asm volatile("nop; nop; nop; nop");
		yield();
	}
}

static void do_start_seq(void)
{
	uint32_t edge_cnt_last;
	uint32_t edge_cnt;
	uint32_t start, t1, t2;
	int tout;

	start = micros();
	edge_cnt = g.edge_cnt;

	/* magic value */
	g.fixed_state[0] =
	g.fixed_state[1] = 0x25;

	for (tout = 10000; tout > 0; tout--) {
		edge_cnt_last = edge_cnt;
		udelay(100);
		edge_cnt = g.edge_cnt;

		if (edge_cnt != edge_cnt_last)
			continue;
		if (!(GPIOB_PDIR & CORE_PIN0_BITMASK))
			break;
	}

	g.fixed_state[0] = 0x33;
	g.fixed_state[1] = 0x3f;
	GPIOD_PDOR = 0x33;

	t1 = micros();
	if (tout == 0) {
		printf("start_seq timeout1, t=%u\n", t1 - start);
		return;
	}

	for (tout = 100000; tout > 0; tout--) {
		udelay(1);

		if (GPIOB_PDIR & CORE_PIN0_BITMASK)
			break;
	}

	t2 = micros();
	if (tout == 0) {
		printf("start_seq timeout2, t1=%u, t2=%u\n",
			t1 - start, t2 - t1);
		return;
	}

	//printf(" t1=%u, t2=%u\n", t1 - start, t2 - t1);

	if (g.stream_started) {
		printf("got start_seq when already started\n");
		return;
	}

	if (!g.stream_enable_to && !g.stream_enable_from) {
		printf("got start_seq, without enable from USB\n");
		return;
	}

	if (g.stream_enable_to && g.t_i == g.t_o) {
		printf("got start_seq while stream_to is empty\n");
		return;
	}

	if (g.stream_enable_from && g.f_i != g.f_o) {
		printf("got start_seq while stream_from is not empty\n");
		return;
	}

	__disable_irq();
	g.stream_started = 1;
	if (g.stream_enable_to) {
		if (g.use_readinc) {
			attachInterruptVector(IRQ_PORTB, portb_isr_do_to_inc);
			attachInterruptVector(IRQ_PORTC, portc_isr_nop);
		}
		else {
			attachInterruptVector(IRQ_PORTB, portb_isr_do_to);
			attachInterruptVector(IRQ_PORTC, portc_isr_frameinc);
		}
	}
	else if (g.stream_enable_from) {
		g.use_pending = 1;
		if (g.use_readinc) {
			attachInterruptVector(IRQ_PORTB,
						portb_isr_fixed_do_from);
			attachInterruptVector(IRQ_PORTC, portc_isr_nop);
		}
		else {
			attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
			attachInterruptVector(IRQ_PORTC,
					      portc_isr_frameinc_do_from);
		}
	}
	__enable_irq();
}

// callers must disable IRQs
static void clear_state(void)
{
	g.stream_enable_to = 0;
	g.stream_enable_from = 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;
	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
}

static int get_space_to(void)
{
	return STREAM_BUF_SIZE - ((g.t_i - g.t_o) & STREAM_BUF_MASK);
}

static int get_used_from(void)
{
	return (g.f_i - g.f_o) & STREAM_BUF_MASK;
}

static void do_usb(void *buf)
{
	struct tas_pkt *pkt = buf;
	uint32_t t_i, i;
	int space;

	switch (pkt->type) {
	case PKT_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();
		clear_state();
		/* wait for start from MD */
		g.stream_enable_to = pkt->enable.stream_to;
		g.stream_enable_from = pkt->enable.stream_from;
		g.use_readinc = pkt->enable.use_readinc;
		__enable_irq();
		break;
	case PKT_STREAM_ABORT:
		__disable_irq();
		clear_state();
		__enable_irq();
		break;
	case PKT_STREAM_END:
		g.stream_ended = 1;
		printf("end of stream\n");
		break;
	case PKT_STREAM_DATA_TO:
		t_i = g.t_i;
		space = get_space_to();
		if (space <= pkt->size / STREAM_EL_SZ) {
			printf("got data pkt while space=%d\n", space);
			return;
		}
		for (i = 0; i < pkt->size / STREAM_EL_SZ; i++) {
			memcpy(&g.stream_to[t_i++],
			       pkt->data + i * STREAM_EL_SZ,
			       STREAM_EL_SZ);
			t_i &= STREAM_BUF_MASK;
		}
		g.t_i = t_i;
		break;
	default:
		printf("got unknown pkt type: %04x\n", pkt->type);
		break;
	}
}

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 ret;

	delay(1000); // wait for usb..

	/* ?0SA 00DU, ?1CB RLDU */
	g.fixed_state[0] = 0x33;
	g.fixed_state[1] = 0x3f;

	printf("starting, rawhid: %d\n", usb_rawhid_available());

	// md pin   th tr tl  r  l  d  u vsync
	// md bit*   6  5  4  3  2  1  0
	// t bit   b16 d5 d4 d3 d2 d1 d0    c6
	// t pin     0 20  6  8  7 14  2    11
	// * - note: tl/tr mixed in most docs
	pinMode(0, INPUT);
	attachInterrupt(0, portb_isr_fixed, CHANGE);
	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	pinMode(11, INPUT);
	attachInterrupt(11, portc_isr_nop, RISING);
	attachInterruptVector(IRQ_PORTC, portc_isr_nop);

	NVIC_SET_PRIORITY(IRQ_PORTB, 0);
	NVIC_SET_PRIORITY(IRQ_PORTC, 16);

	pinMode( 2, OUTPUT);
	pinMode(14, OUTPUT);
	pinMode( 7, OUTPUT);
	pinMode( 8, OUTPUT);
	pinMode( 6, OUTPUT);
	pinMode(20, OUTPUT);

	// led
	pinMode(13, OUTPUT);

	// CORE_PIN0_PORTSET CORE_PIN0_BITMASK PORTB_PCR16
	printf("GPIOB PDDR, PDIR: %08x %08x\n", GPIOB_PDIR, GPIOB_PDDR);
	printf("GPIOC PDDR, PDIR: %08x %08x\n", GPIOC_PDIR, GPIOC_PDDR);
	printf("GPIOD PDDR, PDIR: %08x %08x\n", GPIOD_PDIR, GPIOD_PDDR);
	printf("PORTB_PCR16: %08x\n", PORTB_PCR16);
	printf("PORTC_PCR6:  %08x\n", PORTC_PCR6);

	asm("mrs %0, BASEPRI" : "=r"(ret));
	printf("BASEPRI: %d\n", ret);

	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;

			ret = usb_rawhid_send(&pkt, 1000);
			if (ret != sizeof(pkt)) {
				printf("send STREAM_REQ: %d\n", ret);
				break;
			}

			ret = usb_rawhid_recv(buf, 1000);
			if (ret != 64)
				printf("usb_rawhid_recv/s: %d\n", ret);
			else
				do_usb(buf);
		}

		while (g.stream_enable_from && !g.stream_ended
		  && get_used_from() >= sizeof(pkt.data) / STREAM_EL_SZ)
		{
			uint32_t f_o;
			int i;

			f_o = g.f_o;
			for (i = 0; i < sizeof(pkt.data); i += STREAM_EL_SZ) {
				memcpy(pkt.data + i, &g.stream_from[f_o++],
					STREAM_EL_SZ);
				f_o &= STREAM_BUF_MASK;
			}
			g.f_o = f_o;

			pkt.type = PKT_STREAM_DATA_FROM;
			pkt.size = i;

			ret = usb_rawhid_send(&pkt, 1000);
			if (ret != sizeof(pkt)) {
				printf("send DATA_FROM: %d\n", ret);
				break;
			}
		}

		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 ((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;
		}

		// led?
		if (CORE_PIN13_PORTREG & CORE_PIN13_BITMASK) {
			if ((int)(now - led_time) > 10)
				CORE_PIN13_PORTCLEAR = CORE_PIN13_BITMASK;
		}

		// 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);
			}
		}
	}

	return 0;
}
Commit	Line	Data
	1	/*
	2	* TeensyTAS, TAS input player for MegaDrive
	3	* Copyright (c) 2014 notaz
	4	*
	5	* Permission is hereby granted, free of charge, to any person obtaining
	6	* a copy of this software and associated documentation files (the
	7	* "Software"), to deal in the Software without restriction, including
	8	* without limitation the rights to use, copy, modify, merge, publish,
	9	* distribute, sublicense, and/or sell copies of the Software, and to
	10	* permit persons to whom the Software is furnished to do so, subject to
	11	* the following conditions:
	12	*
	13	* The above copyright notice and this permission notice shall be
	14	* included in all copies or substantial portions of the Software.
	15	*
	16	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	17	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	18	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	19	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	20	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	21	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	22	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	23	* SOFTWARE.
	24	*/
	25
	26	#include <stdint.h>
	27	#include <stdio.h>
	28	#include <string.h>
	29	#include "teensy3/core_pins.h"
	30	#include "teensy3/usb_seremu.h"
	31	#include "teensy3/usb_rawhid.h"
	32	#include "pkts.h"
	33
	34	#define noinline __attribute__((noinline))
	35
	36	// use power of 2
	37	#define STREAM_BUF_SIZE 512
	38	#define STREAM_BUF_MASK (512 - 1)
	39
	40	/* ?0SA 00DU, ?1CB RLDU */
	41	#define STREAM_EL_SZ 2
	42
	43	static struct {
	44	uint8_t stream_to[STREAM_BUF_SIZE][STREAM_EL_SZ];
	45	uint8_t stream_from[STREAM_BUF_SIZE][STREAM_EL_SZ];
	46	union {
	47	uint8_t fixed_state[4];
	48	uint32_t fixed_state32;
	49	};
	50	union {
	51	uint8_t pending_state[4];
	52	uint32_t pending_state32;
	53	};
	54	uint32_t stream_enable_to:1;
	55	uint32_t stream_enable_from:1;
	56	uint32_t stream_started:1;
	57	uint32_t stream_ended:1;
	58	uint32_t use_readinc:1;
	59	uint32_t use_pending:1;
	60	uint32_t frame_cnt;
	61	uint32_t edge_cnt;
	62	uint32_t t_i;
	63	uint32_t t_o;
	64	uint32_t f_i;
	65	uint32_t f_o;
	66	} g;
	67
	68	ssize_t _write(int fd, const void *buf, size_t nbyte)
	69	{
	70	char tbuf[64];
	71	int ret;
	72
	73	if (fd != 1 && fd != 2) {
	74	snprintf(tbuf, sizeof(tbuf), "write to fd %d\n", fd);
	75	usb_seremu_write(tbuf, strlen(tbuf));
	76	}
	77
	78	ret = usb_seremu_write(buf, nbyte);
	79	return ret < 0 ? ret : nbyte;
	80	}
	81
	82	void yield(void)
	83	{
	84	}
	85
	86	/* portb handles TH */
	87	static void portb_isr_fixed(void)
	88	{
	89	uint32_t isfr, th;
	90
	91	isfr = PORTB_ISFR;
	92	PORTB_ISFR = isfr;
	93	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
	94
	95	GPIOD_PDOR = g.fixed_state[th];
	96	g.edge_cnt++;
	97	}
	98
	99	static void portb_isr_do_to_inc(void)
	100	{
	101	uint32_t isfr, th;
	102
	103	isfr = PORTB_ISFR;
	104	PORTB_ISFR = isfr;
	105	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
	106
	107	GPIOD_PDOR = g.stream_to[g.t_o][th];
	108	if (th) {
	109	g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
	110	if (g.t_o == g.t_i)
	111	// done
	112	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	113	g.frame_cnt++;
	114	}
	115	g.edge_cnt++;
	116	}
	117
	118	static void portb_isr_do_to(void)
	119	{
	120	uint32_t isfr, th;
	121
	122	isfr = PORTB_ISFR;
	123	PORTB_ISFR = isfr;
	124	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
	125
	126	GPIOD_PDOR = g.stream_to[g.t_o][th];
	127	g.edge_cnt++;
	128	}
	129
	130	static void portc_isr_nop(void)
	131	{
	132	uint32_t isfr;
	133
	134	isfr = PORTC_ISFR;
	135	PORTC_ISFR = isfr;
	136	}
	137
	138	// /vsync starts at line 235/259 (ntsc/pal), just as vcounter jumps back
	139	// we care when it comes out (/vsync goes high) after 3 lines at 238/262
	140	static void portc_isr_frameinc(void)
	141	{
	142	uint32_t isfr;
	143
	144	isfr = PORTC_ISFR;
	145	PORTC_ISFR = isfr;
	146
	147	g.t_o = (g.t_o + 1) & STREAM_BUF_MASK;
	148	if (g.t_o == g.t_i) {
	149	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	150	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	151	}
	152	g.frame_cnt++;
	153	}
	154
	155	/* "recording" data */
	156	static noinline void do_from_step(void)
	157	{
	158	uint32_t s;
	159
	160	// should hopefully give atomic fixed_state read..
	161	s = g.fixed_state32;
	162	g.fixed_state32 = g.pending_state32;
	163	g.stream_from[g.f_i][0] = s;
	164	g.stream_from[g.f_i][1] = s >> 8;
	165	g.f_i = (g.f_i + 1) & STREAM_BUF_MASK;
	166	}
	167
	168	static void portb_isr_fixed_do_from(void)
	169	{
	170	uint32_t isfr, th;
	171
	172	isfr = PORTB_ISFR;
	173	PORTB_ISFR = isfr;
	174	th = (GPIOB_PDIR >> CORE_PIN0_BIT) & 1;
	175
	176	GPIOD_PDOR = g.fixed_state[th];
	177	if (th)
	178	do_from_step();
	179	g.edge_cnt++;
	180	}
	181
	182	static void portc_isr_frameinc_do_from(void)
	183	{
	184	uint32_t isfr;
	185
	186	isfr = PORTC_ISFR;
	187	PORTC_ISFR = isfr;
	188
	189	do_from_step();
	190	g.frame_cnt++;
	191	}
	192
	193	static void udelay(uint32_t us)
	194	{
	195	uint32_t start = micros();
	196
	197	while ((micros() - start) < us) {
	198	asm volatile("nop; nop; nop; nop");
	199	yield();
	200	}
	201	}
	202
	203	static void do_start_seq(void)
	204	{
	205	uint32_t edge_cnt_last;
	206	uint32_t edge_cnt;
	207	uint32_t start, t1, t2;
	208	int tout;
	209
	210	start = micros();
	211	edge_cnt = g.edge_cnt;
	212
	213	/* magic value */
	214	g.fixed_state[0] =
	215	g.fixed_state[1] = 0x25;
	216
	217	for (tout = 10000; tout > 0; tout--) {
	218	edge_cnt_last = edge_cnt;
	219	udelay(100);
	220	edge_cnt = g.edge_cnt;
	221
	222	if (edge_cnt != edge_cnt_last)
	223	continue;
	224	if (!(GPIOB_PDIR & CORE_PIN0_BITMASK))
	225	break;
	226	}
	227
	228	g.fixed_state[0] = 0x33;
	229	g.fixed_state[1] = 0x3f;
	230	GPIOD_PDOR = 0x33;
	231
	232	t1 = micros();
	233	if (tout == 0) {
	234	printf("start_seq timeout1, t=%u\n", t1 - start);
	235	return;
	236	}
	237
	238	for (tout = 100000; tout > 0; tout--) {
	239	udelay(1);
	240
	241	if (GPIOB_PDIR & CORE_PIN0_BITMASK)
	242	break;
	243	}
	244
	245	t2 = micros();
	246	if (tout == 0) {
	247	printf("start_seq timeout2, t1=%u, t2=%u\n",
	248	t1 - start, t2 - t1);
	249	return;
	250	}
	251
	252	//printf(" t1=%u, t2=%u\n", t1 - start, t2 - t1);
	253
	254	if (g.stream_started) {
	255	printf("got start_seq when already started\n");
	256	return;
	257	}
	258
	259	if (!g.stream_enable_to && !g.stream_enable_from) {
	260	printf("got start_seq, without enable from USB\n");
	261	return;
	262	}
	263
	264	if (g.stream_enable_to && g.t_i == g.t_o) {
	265	printf("got start_seq while stream_to is empty\n");
	266	return;
	267	}
	268
	269	if (g.stream_enable_from && g.f_i != g.f_o) {
	270	printf("got start_seq while stream_from is not empty\n");
	271	return;
	272	}
	273
	274	__disable_irq();
	275	g.stream_started = 1;
	276	if (g.stream_enable_to) {
	277	if (g.use_readinc) {
	278	attachInterruptVector(IRQ_PORTB, portb_isr_do_to_inc);
	279	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	280	}
	281	else {
	282	attachInterruptVector(IRQ_PORTB, portb_isr_do_to);
	283	attachInterruptVector(IRQ_PORTC, portc_isr_frameinc);
	284	}
	285	}
	286	else if (g.stream_enable_from) {
	287	g.use_pending = 1;
	288	if (g.use_readinc) {
	289	attachInterruptVector(IRQ_PORTB,
	290	portb_isr_fixed_do_from);
	291	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	292	}
	293	else {
	294	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	295	attachInterruptVector(IRQ_PORTC,
	296	portc_isr_frameinc_do_from);
	297	}
	298	}
	299	__enable_irq();
	300	}
	301
	302	// callers must disable IRQs
	303	static void clear_state(void)
	304	{
	305	g.stream_enable_to = 0;
	306	g.stream_enable_from = 0;
	307	g.stream_started = 0;
	308	g.stream_ended = 0;
	309	g.use_readinc = 0;
	310	g.use_pending = 0;
	311	g.t_i = g.t_o = 0;
	312	g.f_i = g.f_o = 0;
	313	g.frame_cnt = 0;
	314	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	315	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	316	}
	317
	318	static int get_space_to(void)
	319	{
	320	return STREAM_BUF_SIZE - ((g.t_i - g.t_o) & STREAM_BUF_MASK);
	321	}
	322
	323	static int get_used_from(void)
	324	{
	325	return (g.f_i - g.f_o) & STREAM_BUF_MASK;
	326	}
	327
	328	static void do_usb(void *buf)
	329	{
	330	struct tas_pkt *pkt = buf;
	331	uint32_t t_i, i;
	332	int space;
	333
	334	switch (pkt->type) {
	335	case PKT_FIXED_STATE:
	336	memcpy(&i, pkt->data, sizeof(i));
	337	if (g.use_pending)
	338	g.pending_state32 = i;
	339	else
	340	g.fixed_state32 = i;
	341	break;
	342	case PKT_STREAM_ENABLE:
	343	__disable_irq();
	344	clear_state();
	345	/* wait for start from MD */
	346	g.stream_enable_to = pkt->enable.stream_to;
	347	g.stream_enable_from = pkt->enable.stream_from;
	348	g.use_readinc = pkt->enable.use_readinc;
	349	__enable_irq();
	350	break;
	351	case PKT_STREAM_ABORT:
	352	__disable_irq();
	353	clear_state();
	354	__enable_irq();
	355	break;
	356	case PKT_STREAM_END:
	357	g.stream_ended = 1;
	358	printf("end of stream\n");
	359	break;
	360	case PKT_STREAM_DATA_TO:
	361	t_i = g.t_i;
	362	space = get_space_to();
	363	if (space <= pkt->size / STREAM_EL_SZ) {
	364	printf("got data pkt while space=%d\n", space);
	365	return;
	366	}
	367	for (i = 0; i < pkt->size / STREAM_EL_SZ; i++) {
	368	memcpy(&g.stream_to[t_i++],
	369	pkt->data + i * STREAM_EL_SZ,
	370	STREAM_EL_SZ);
	371	t_i &= STREAM_BUF_MASK;
	372	}
	373	g.t_i = t_i;
	374	break;
	375	default:
	376	printf("got unknown pkt type: %04x\n", pkt->type);
	377	break;
	378	}
	379	}
	380
	381	int main(void)
	382	{
	383	uint32_t led_time = 0;
	384	uint32_t scheck_time = 0;
	385	uint32_t edge_cnt_last;
	386	uint32_t edge_cnt;
	387	uint8_t buf[64];
	388	int ret;
	389
	390	delay(1000); // wait for usb..
	391
	392	/* ?0SA 00DU, ?1CB RLDU */
	393	g.fixed_state[0] = 0x33;
	394	g.fixed_state[1] = 0x3f;
	395
	396	printf("starting, rawhid: %d\n", usb_rawhid_available());
	397
	398	// md pin th tr tl r l d u vsync
	399	// md bit* 6 5 4 3 2 1 0
	400	// t bit b16 d5 d4 d3 d2 d1 d0 c6
	401	// t pin 0 20 6 8 7 14 2 11
	402	// * - note: tl/tr mixed in most docs
	403	pinMode(0, INPUT);
	404	attachInterrupt(0, portb_isr_fixed, CHANGE);
	405	attachInterruptVector(IRQ_PORTB, portb_isr_fixed);
	406	pinMode(11, INPUT);
	407	attachInterrupt(11, portc_isr_nop, RISING);
	408	attachInterruptVector(IRQ_PORTC, portc_isr_nop);
	409
	410	NVIC_SET_PRIORITY(IRQ_PORTB, 0);
	411	NVIC_SET_PRIORITY(IRQ_PORTC, 16);
	412
	413	pinMode( 2, OUTPUT);
	414	pinMode(14, OUTPUT);
	415	pinMode( 7, OUTPUT);
	416	pinMode( 8, OUTPUT);
	417	pinMode( 6, OUTPUT);
	418	pinMode(20, OUTPUT);
	419
	420	// led
	421	pinMode(13, OUTPUT);
	422
	423	// CORE_PIN0_PORTSET CORE_PIN0_BITMASK PORTB_PCR16
	424	printf("GPIOB PDDR, PDIR: %08x %08x\n", GPIOB_PDIR, GPIOB_PDDR);
	425	printf("GPIOC PDDR, PDIR: %08x %08x\n", GPIOC_PDIR, GPIOC_PDDR);
	426	printf("GPIOD PDDR, PDIR: %08x %08x\n", GPIOD_PDIR, GPIOD_PDDR);
	427	printf("PORTB_PCR16: %08x\n", PORTB_PCR16);
	428	printf("PORTC_PCR6: %08x\n", PORTC_PCR6);
	429
	430	asm("mrs %0, BASEPRI" : "=r"(ret));
	431	printf("BASEPRI: %d\n", ret);
	432
	433	edge_cnt_last = g.edge_cnt;
	434
	435	while (1) {
	436	struct tas_pkt pkt;
	437	uint32_t now;
	438
	439	while (g.stream_enable_to && !g.stream_ended
	440	&& get_space_to() > sizeof(pkt.data) / STREAM_EL_SZ)
	441	{
	442	if (g.t_i == g.t_o && g.frame_cnt != 0) {
	443	printf("underflow detected\n");
	444	g.stream_enable_to = 0;
	445	break;
	446	}
	447
	448	pkt.type = PKT_STREAM_REQ;
	449	pkt.req.frame = g.frame_cnt;
	450
	451	ret = usb_rawhid_send(&pkt, 1000);
	452	if (ret != sizeof(pkt)) {
	453	printf("send STREAM_REQ: %d\n", ret);
	454	break;
	455	}
	456
	457	ret = usb_rawhid_recv(buf, 1000);
	458	if (ret != 64)
	459	printf("usb_rawhid_recv/s: %d\n", ret);
	460	else
	461	do_usb(buf);
	462	}
	463
	464	while (g.stream_enable_from && !g.stream_ended
	465	&& get_used_from() >= sizeof(pkt.data) / STREAM_EL_SZ)
	466	{
	467	uint32_t f_o;
	468	int i;
	469
	470	f_o = g.f_o;
	471	for (i = 0; i < sizeof(pkt.data); i += STREAM_EL_SZ) {
	472	memcpy(pkt.data + i, &g.stream_from[f_o++],
	473	STREAM_EL_SZ);
	474	f_o &= STREAM_BUF_MASK;
	475	}
	476	g.f_o = f_o;
	477
	478	pkt.type = PKT_STREAM_DATA_FROM;
	479	pkt.size = i;
	480
	481	ret = usb_rawhid_send(&pkt, 1000);
	482	if (ret != sizeof(pkt)) {
	483	printf("send DATA_FROM: %d\n", ret);
	484	break;
	485	}
	486	}
	487
	488	now = millis();
	489
	490	// start condition check
	491	if (now - scheck_time > 1000) {
	492	edge_cnt = g.edge_cnt;
	493	//printf("e: %d th: %d\n", edge_cnt - edge_cnt_last,
	494	// (GPIOB_PDIR >> CORE_PIN0_BIT) & 1);
	495	if ((g.stream_enable_to \|\| g.stream_enable_from)
	496	&& !g.stream_started
	497	&& edge_cnt - edge_cnt_last > 10000)
	498	{
	499	do_start_seq();
	500	edge_cnt = g.edge_cnt;
	501	}
	502	edge_cnt_last = edge_cnt;
	503	scheck_time = now;
	504	}
	505
	506	// led?
	507	if (CORE_PIN13_PORTREG & CORE_PIN13_BITMASK) {
	508	if ((int)(now - led_time) > 10)
	509	CORE_PIN13_PORTCLEAR = CORE_PIN13_BITMASK;
	510	}
	511
	512	// something on rawhid?
	513	if (usb_rawhid_available() > 0)
	514	{
	515	ret = usb_rawhid_recv(buf, 20);
	516	if (ret == 64) {
	517	led_time = millis();
	518	CORE_PIN13_PORTSET = CORE_PIN13_BITMASK;
	519
	520	do_usb(buf);
	521	}
	522	else {
	523	printf("usb_rawhid_recv: %d\n", ret);
	524	}
	525	}
	526	}
	527
	528	return 0;
	529	}