path: root/avr/z180-serv.c

/*
 * (C) Copyright 2014-2016 Leo C. <erbl259-lmu@yahoo.de>
 *
 * SPDX-License-Identifier:	GPL-2.0
 */

#include "z180-serv.h"
#include "common.h"
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <util/atomic.h>

#include "config.h"
#include "background.h"
#include "env.h"
#include "ff.h"
#include "serial.h"
#include "z80-if.h"
#include "debug.h"
#include "print-utils.h"
#include "timer.h"
#include "time.h"
#include "bcd.h"
#include "rtc.h"

#define DEBUG_CPM_SDIO	0	/* set to 1 to debug */

#define debug_cpmsd(fmt, args...)		                                            \
	debug_cond(DEBUG_CPM_SDIO, fmt, ##args)


/*--------------------------------------------------------------------------*/

struct msg_item {
	uint8_t fct;
	uint8_t sub_min, sub_max;
	void (*func)(uint8_t, int, uint8_t *);
};

uint32_t msg_to_addr(uint8_t *msg)
{
	union {
		uint32_t as32;
		uint8_t as8[4];
	} addr;

	addr.as8[0] = msg[0];
	addr.as8[1] = msg[1];
	addr.as8[2] = msg[2];
	addr.as8[3] = 0;

	return addr.as32;
}


static int msg_xmit_header(uint8_t func, uint8_t subf, int len)
{
	z80_memfifo_putc(fifo_msgout, 0xAE);
	z80_memfifo_putc(fifo_msgout, len+2);
	z80_memfifo_putc(fifo_msgout, func);
	z80_memfifo_putc(fifo_msgout, subf);

	return 0;
}

int msg_xmit(uint8_t func, uint8_t subf, int len, uint8_t *msg)
{
	msg_xmit_header(func, subf, len);
	while (len--)
		z80_memfifo_putc(fifo_msgout, *msg++);

	return 0;
}

void do_msg_ini_memfifo(uint8_t subf, int len, uint8_t * msg)
{
	(void)len;

	z80_memfifo_init(subf, msg_to_addr(msg));
}


void do_msg_char_out(uint8_t subf, int len, uint8_t * msg)
{
	(void)subf;

	while (len--)
		putchar(*msg++);
}

/* echo message */
void do_msg_echo(uint8_t subf, int len, uint8_t * msg)
{
	(void)subf;

	/* send re-echo */
	msg_xmit(1, 3, len, msg);
}

/* get timer */
void do_msg_get_timer(uint8_t subf, int len, uint8_t * msg)
{
	uint32_t time_ms = (len >= 4) ? *(uint32_t *) msg : 0;

	time_ms = get_timer(time_ms);
	msg_xmit(3, subf, sizeof(time_ms), (uint8_t *) &time_ms);
}

/* ---------------------------------------------------------------------------*/

#define CPM_DAY_OFFSET ((1978-1900) * 365 + 19)		/* 19 leap years */

/*
 * Convert CP/M time stamp to a broken-down time structure
 *
 */
int mk_date_time (int len, uint8_t *msg, struct tm *tmp)
{
	time_t stamp;

	if (len != 5)
		return -1;

	/* days since 2000-01-01 */
	long days = msg[3] + (msg[4] << 8) - 8036;

	if (days < 0)
		return -1;

	stamp = days * ONE_DAY;
	stamp += bcd2bin(msg[0]);
	stamp += bcd2bin(msg[1]) * 60 ;
	stamp += bcd2bin(msg[2]) * 3600L;
	gmtime_r(&stamp, tmp);
	return 0;
}

void mk_cpm_time(struct tm *tmp, uint8_t cpm_time[5])
{
	uint16_t days = 1;
	uint_fast8_t leap=2;

	for (int year=78; year < tmp->tm_year; year++) {
		days = days + 365 + (leap == 0);
		leap = (leap+1)%4;
	}
	days += tmp->tm_yday;

	cpm_time[0] = bin2bcd(tmp->tm_sec);
	cpm_time[1] = bin2bcd(tmp->tm_min);
	cpm_time[2] = bin2bcd(tmp->tm_hour);
	cpm_time[3] = days;
	cpm_time[4] = days >> 8;
}

/* get/set cp/m time */
void do_msg_get_set_time(uint8_t subf, int len, uint8_t * msg)
{
	struct tm t;
	uint8_t cpm_time[5];
	int rc;

	memset(cpm_time, 0, ARRAY_SIZE(cpm_time));

	switch (subf) {
	case 3:			/* set date & time */
		/* initialize t with current time */
		rc = rtc_get (&t);

		if (rc >= 0) {
			/* insert new date & time */
			if (mk_date_time (len, msg, &t) != 0) {
				my_puts_P(PSTR("## set_time: Bad date format\n"));
				break;
			}

			time_t time;
			time = mk_gmtime(&t);
			gmtime_r(&time, &t);

			/* and write to RTC */
			rc = rtc_set (&t);
			if(rc)
				my_puts_P(PSTR("## set_time: Set date failed\n"));
		} else {
			my_puts_P(PSTR("## set_time: Get date failed\n"));
		}
		/* FALL TROUGH */
	case 2:			/* get date & time */
		rc = rtc_get (&t);
		if (rc >= 0) {
			time_t time;
			time = mk_gmtime(&t);
			//mktime(&t);
			gmtime_r(&time, &t);

			mk_cpm_time(&t, cpm_time);
		} else {
			my_puts_P(PSTR("## get_time: Get date failed\n"));
		}
		break;
	}

	msg_xmit(3, subf, sizeof(cpm_time), cpm_time);
}

/* ---------------------------------------------------------------------------*/

static uint8_t drv;
static uint8_t disk_buffer[CONFIG_CPM_BLOCK_SIZE];
static struct cpm_drive_s drv_table[CONFIG_CPM_MAX_DRIVE];
static int handle_cpm_drv_to;

typedef enum {SINGLE, START, MIDDLE, END} dbgmsg_t;

void drv_debug(dbgmsg_t phase, const FLASH char *const fmt, ...)		                                            \
{
	struct cpm_drive_s *dp = &drv_table[drv];

	if (dp->opt & DRV_OPT_DEBUG) {

		va_list ap;
		va_start (ap, fmt);

		if (phase == SINGLE || phase == START)
			printf_P(PSTR("# %7lu dsk%d: "), get_timer(0), drv);

		vfprintf_P (stdout, fmt, ap);

		if (phase == SINGLE || phase == END)
			putc('\n', stdout);

		va_end (ap);
	}
}

int drv_list(void)
{
	for (uint8_t i = 0; i < CONFIG_CPM_MAX_DRIVE; i++) {
		struct cpm_drive_s * p = &drv_table[i];
		if (p->img_name) {
			printf_P(PSTR("  dsk%d: %2s %3s attached to %s\n"), i,
					p->opt&DRV_OPT_RO ? "RO":"RW", p->opt&DRV_OPT_DEBUG ? "DBG":"",
					p->img_name);
		}
	}
	return 0;
}

int drv_detach(uint8_t unit)
{
	drv = unit;
	if (drv < CONFIG_CPM_MAX_DRIVE) {
		struct cpm_drive_s *p = &drv_table[drv];

		drv_debug(SINGLE, PSTR("detach from '%s'"), p->img_name ? p->img_name : "-");

		if (p->img_name) {
			f_close(&p->fd);
			free(p->img_name);
			p->opt = 0;
			p->flags &= ~DRV_FLG_DIRTY;
			p->img_name = NULL;

			uint32_t scb = getenv_ulong(PSTR(ENV_CPM3_SCB), 16, 0);
			if (scb && (z80_bus_cmd(Request) & ZST_ACQUIRED)) {
				z80_write(scb + 0xf0, 0xff);
				z80_write(p->dph + 11, 0xff);
				z80_bus_cmd(Release);
			}
		}
	}
	return 0;
}

static int drv_find_file_attached(const char *fn)
{
	for (uint8_t i = 0; i < CONFIG_CPM_MAX_DRIVE; i++) {
		struct cpm_drive_s *p = &drv_table[i];
		if (p->img_name && !strcmp(fn, p->img_name)) {
			return i;
		}
	}
	return -1;
}

int drv_attach(uint8_t unit, const char *filename, drv_opt_t options)
{
	int res;

	drv = unit;
	if (drv >= CONFIG_CPM_MAX_DRIVE)
		return AT_RANGE;

	struct cpm_drive_s *p = &drv_table[drv];

	if (options & DRV_OPT_REATTATCH) {
		if (filename) {
			return AT_ERROR;
		}

		if (!p->img_name) {
			return AT_NOT;
		}

		/* change options */
		if ((p->opt ^ options) & DRV_OPT_RO) {
			f_close(&p->fd);
			res = f_open(&p->fd, p->img_name,
					FA_READ | (options&DRV_OPT_RO ? 0 : FA_WRITE));
		}

		p->opt = options & ~DRV_OPT_REATTATCH;

	} else {

		if (p->img_name)
			return AT_ALREADY;
		if (drv_find_file_attached(filename) >= 0)
			return AT_OTHER;

		p->opt = options;

		/* new attachment */

		if ((p->img_name = strdup(filename)) == NULL)
			return AT_NOMEM;

		res = f_open(&p->fd, p->img_name,
				FA_READ | (options&DRV_OPT_RO ? 0 : FA_WRITE));

		if (!res && f_size(&p->fd) < CONFIG_CPM_DISKSIZE) {
#if 0
			unsigned int bw;
			debug_cpmsd("            expanding image file from %ld to %ld\n",
					f_size(&p->fd), CONFIG_CPM_DISKSIZE);

			res = f_lseek(&p->fd, CONFIG_CPM_DISKSIZE-CONFIG_CPM_BLOCK_SIZE);
			if (!res) {
				memset(disk_buffer, 0xe5, CONFIG_CPM_BLOCK_SIZE);
				res = f_write(&p->fd, disk_buffer, CONFIG_CPM_BLOCK_SIZE, &bw);
				if (res || bw < CONFIG_CPM_BLOCK_SIZE) {
					debug_cpmsd("               failed! res: %d, bytes written: %u\n",	res, bw);
				}
				p->flags |= DRV_FLG_DIRTY;
				bg_setstat(handle_cpm_drv_to, 1);
			}
#else
			drv_debug(SINGLE, PSTR("wrong image file size: %ld, should be %ld"),
					f_size(&p->fd), CONFIG_CPM_DISKSIZE);
			res = 64;
#endif
		}
		if (res) {
			drv_detach(drv);
			return AT_OPEN;
		}
	}

	return AT_OK;
}


int cpm_drv_to(int state)
{
	static uint32_t ts;

	switch(state) {
	case 0:
		break;

	case 1:
		ts = get_timer(0);
		state = 2;
		break;

	case 2:
		if (get_timer(ts) > 1000) {
			for (uint_fast8_t i=0; i < CONFIG_CPM_MAX_DRIVE; i++) {
				if (drv_table[i].flags & DRV_FLG_DIRTY) {
					drv_table[i].flags &= ~DRV_FLG_DIRTY;
					f_sync(&drv_table[i].fd);
					drv = i;
					drv_debug(SINGLE, PSTR("f_sync"));
				}
			}
			state = 0;
		}
	}
	return state;
}

static const FLASH char * const FLASH rc_messages[] = {
			FSTR("OK"),
			FSTR("Internal error: wrong message len"),	/* 01 */
			FSTR("Invalid relative drive #"),			/* 02 */
			FSTR("Bus timeout"),						/* 03 */
			FSTR("Access byond disk size"),				/* 04 */
			FSTR("Write protect"),						/* 05 */
			FSTR("No media"),							/* 06 */
			FSTR("R/W address == 0 !!!!"),				/* 07 */
		};

void msg_cpm_result(uint8_t subf, uint8_t rc, int res)
{
	uint8_t result_msg[3];

	if (res)
		rc |= 0x80;

	result_msg[0] = rc;
	result_msg[1] = res;
	result_msg[2] = res >> 8;

	msg_xmit(2, subf, sizeof(result_msg), result_msg);

	if (rc) {
#if GCC_BUG_61443
		char msg[40];
		strncpy_P(msg, rc_messages[rc & 0x7f], sizeof msg -1);
		drv_debug(END, PSTR(" rc: %.02x/%d, '%s'"),
					rc, res, msg);
#else
		drv_debug(END, PSTR(" rc: %.02x/%d, '%S'"),
					rc, res, rc_messages[rc & 0x7f]);
#endif
	} else
		drv_debug(END, PSTR(""));

}

/*
 	db	2	; disk command
	ds	1	; subcommand (login/read/write)
	ds	1	; @adrv (8 bits)	+0
	ds	1	; @rdrv (8 bits)	+1
	ds	3	; @xdph (24 bits)	+2
*/

void do_msg_cpm_login(uint8_t subf, int len, uint8_t * msg)
{
	struct cpm_drive_s *dp;
	FRESULT res = 0;

	(void)subf;

	/* Get relative drive number */
	drv = msg[1];
	drv_debug(START, PSTR("login"));

	if (len != 5) {
		return msg_cpm_result(subf, 0x01, res);
	}

	if ( drv >= CONFIG_CPM_MAX_DRIVE) {
		/* invalid relative drive number */
		return msg_cpm_result(subf, 0x02, res);
	}

	dp = &drv_table[drv];
	dp->flags &= ~DRV_FLG_OPEN;
	dp->dph = ((uint32_t)msg[4] << 16) + ((uint16_t)msg[3] << 8) + msg[2];

	if (dp->img_name == NULL) {
		/* no file attached */
		return msg_cpm_result(subf, 0x06, res);
	}

	f_close(&dp->fd);
	res = f_open(&dp->fd, dp->img_name,
			FA_READ | (dp->opt&DRV_OPT_RO ? 0 : FA_WRITE));

	dp->flags |= DRV_FLG_OPEN;

	/* send  result*/
	msg_cpm_result(subf, 0x00, res);
}


/*
 	db	2	; disk command
	ds	1	; subcommand (login/read/write)
	ds	1	; @adrv (8 bits)		+0
	ds	1	; @rdrv (8 bits)		+1
	ds	2	; @trk (16 bits)		+2
	ds	2	; @sect(16 bits)		+4
	ds	1	; @cnt  (8 bits)		+6
	ds	3	; phys. transfer addr	+7
*/

#define ADRV	0
#define RDRV	1
#define TRK		2
#define SEC		4
#define CNT		6
#define ADDR	7

void do_msg_cpm_rw(uint8_t subf, int len, uint8_t * msg)
{
	struct cpm_drive_s *dp;
	uint32_t addr;
	uint32_t pos;
	uint16_t track;
	uint16_t sec;
	uint8_t secs;
	bool dowrite;
	FRESULT res = 0;
	uint8_t rc = 0;
	bool buserr = 0;

	drv = msg[RDRV];
	dowrite = (subf == 2);

	drv_debug(START, PSTR("%2S"), dowrite ? PSTR("W ") : PSTR(" R"));

	if (len != 10) {
		return msg_cpm_result(subf, 0x01, res);
	}
	if ( drv>= CONFIG_CPM_MAX_DRIVE) {
		return msg_cpm_result(subf, 0x02, res);
	}

	dp = &drv_table[drv];
	track = (uint16_t)(msg[TRK+1] << 8) + msg[TRK];
	sec  = (uint16_t)(msg[SEC+1] << 8) + msg[SEC];
	secs = msg[CNT];
	addr = ((uint32_t)msg[ADDR+2] << 16) + ((uint16_t)msg[ADDR+1] << 8) + msg[ADDR];

	if (dp->img_name == NULL) {
		/* no media */
		return msg_cpm_result(subf, 0x06, res);
	}

	/* TODO: tracks per sector from dpb */
	pos = (track * 8UL + sec) * CONFIG_CPM_BLOCK_SIZE;

	drv_debug(MIDDLE, PSTR(" T:%4d, S:%2d, cnt:%2d, lba: %.8lx, addr: %.5lx"),
				track, sec, secs, pos, addr);

	if (addr == 0) {
		return msg_cpm_result(subf, 0x07, res);
	}

	if (dowrite && dp->opt & DRV_OPT_RO) {
		return msg_cpm_result(subf, 0x05, res);
	}


	if (pos + secs * CONFIG_CPM_BLOCK_SIZE > CONFIG_CPM_DISKSIZE) {
		drv_debug(MIDDLE, PSTR(" access > DISKSIZE:%.8lx!"),
						CONFIG_CPM_DISKSIZE);
		return msg_cpm_result(subf, 0x04, res);
	}

	res = f_lseek(&dp->fd, pos);

	while (!res && secs--) {
		unsigned int brw;
		if (dowrite) {
			if (!(z80_bus_cmd(Request) & ZST_ACQUIRED)) {
				buserr = 1;
				break;
			} else {
				z80_read_block(disk_buffer, addr, CONFIG_CPM_BLOCK_SIZE);
				z80_bus_cmd(Release);
			}
			res = f_write(&dp->fd, disk_buffer, CONFIG_CPM_BLOCK_SIZE, &brw);
		} else {
			res = f_read(&dp->fd, disk_buffer, CONFIG_CPM_BLOCK_SIZE, &brw);
			if (res == FR_OK) {
				if (!(z80_bus_cmd(Request) & ZST_ACQUIRED)) {
					buserr = 1;
					break;
				} else {
					z80_write_block(disk_buffer, addr, CONFIG_CPM_BLOCK_SIZE);
					z80_bus_cmd(Release);
				}
			}
		}
		if (brw != CONFIG_CPM_BLOCK_SIZE) {
			drv_debug(MIDDLE, PSTR(" short rd/wr: res: %d, brw: %u"),
						res, brw);
			res = 64;
		}
		addr += CONFIG_CPM_BLOCK_SIZE;
	}

	if (dowrite && !res) {
		dp->flags |= DRV_FLG_DIRTY;
		bg_setstat(handle_cpm_drv_to, 1);
	}

	if (buserr) {
		/* Bus timeout. how can this happen? */
		rc = 0x03;
	}

	/* send  result*/
	msg_cpm_result(subf, rc, res);
}


const FLASH struct msg_item z80_messages[] =
{
	{ 0,			/* fct nr. */
	  1, 3,			/* sub fct nr. from, to */
	  do_msg_ini_memfifo},
	{ 1,
	  1, 1,
	  do_msg_char_out},
	{ 1,
	  2, 2,
	  do_msg_echo},
	{ 2,
	  0, 0,
	  do_msg_cpm_login},
	{ 2,
	  1, 2,
	  do_msg_cpm_rw},
	{ 3,
	  1, 1,
	  do_msg_get_timer},
	{ 3,
	  2, 3,				/* 2: get, 3: set time and date */
	  do_msg_get_set_time},
	{ 0xff,				/* end mark */
	  0, 0,
	  0},

};




void do_message(int len, uint8_t *msg)
{
	uint8_t fct, sub_fct;
	int_fast8_t i = 0;

	if (len >= 2) {
		fct = *msg++;
		sub_fct = *msg++;
		len -= 2;

		while (fct != z80_messages[i].fct) {
			if (z80_messages[i].fct == 0xff) {
				DBG_P(1, "do_message: Unknown function: %i, %i\n",
						fct, sub_fct);
				return; /* TODO: unknown message # */
			}

			++i;
		}

		while (fct == z80_messages[i].fct) {
			if (sub_fct >= z80_messages[i].sub_min &&
					sub_fct <= z80_messages[i].sub_max )
				break;
			++i;
		}

		if (z80_messages[i].fct != fct) {
			DBG_P(1, "do_message: Unknown sub function: %i, %i\n",
					fct, sub_fct);
			return; /* TODO: unknown message sub# */
		}

		(z80_messages[i].func)(sub_fct, len, msg);


	} else {
		/* TODO: error */
		DBG_P(1, "do_message: to few arguments (%i); this shouldn't happen!\n", len);
	}
}



#define CTRBUF_LEN 256

void check_msg_fifo(void)
{
	int ch;
	static int_fast8_t state;
	static int msglen,idx;
	static uint8_t buffer[CTRBUF_LEN];

	while ((ch = z80_memfifo_getc(fifo_msgin)) >= 0) {
		switch (state) {
		case 0:		/* wait for start of message */
			if (ch == 0xAE)	{ /* TODO: magic number */
				msglen = 0;
				idx = 0;
				state = 1;
			}
			break;
		case 1:		/* get msg len */
			if (ch > 0 && ch <= CTRBUF_LEN) {
				msglen = ch;
				state = 2;
			} else
				state = 0;
			break;
		case 2: 	/* get message */
			buffer[idx++] = ch;
			if (idx == msglen) {
				do_message(msglen, buffer);
				state = 0;
			}
			break;
		}
	}
}


int msg_handling(int state)
{
	bool pending;

	ATOMIC_BLOCK(ATOMIC_FORCEON) {
		pending = (Stat & S_MSG_PENDING) != 0;
		Stat &= ~S_MSG_PENDING;
	}

	if (pending) {
		uint8_t init_request;
		z80_bus_cmd(Request);
		init_request = z80_read(0x43);
		z80_bus_cmd(Release);
		if ( init_request != 0) {
			/* Get address of fifo 0 */
			z80_bus_cmd(Request);
			uint32_t fifo_addr = z80_read(0x40) +
						((uint16_t) z80_read(0x40+1) << 8) +
						((uint32_t) z80_read(0x40+2) << 16);
			z80_write(0x43, 0);
			z80_bus_cmd(Release);

			if (fifo_addr != 0) {
				z80_memfifo_init(fifo_msgin, fifo_addr);
				state = 1;
			} else
				state = 0;

		} else {
			check_msg_fifo();
		}
	}

	return state;
}


static int handle_msg_handling;

void setup_z180_serv(void)
{

	handle_msg_handling = bg_register(msg_handling, 0);
	handle_cpm_drv_to = bg_register(cpm_drv_to, 0);
}

void restart_z180_serv(void)
{
	z80_bus_cmd(Request);
	z80_memset(0x40, 0, 4);
	z80_bus_cmd(Release);

	for (int i = 0; i < NUM_FIFOS; i++)
		z80_memfifo_init(i, 0);
	bg_setstat(handle_msg_handling, 0);

}

#if 0
/*--------------------------------------------------------------------------*/

const FLASH uint8_t iniprog[] = {
	0xAF,			// xor     a
	0xED, 0x39, 0x36,	// out0    (rcr),a         ;disable  DRAM refresh
	0x3E, 0x30,		// ld      a,030h
	0xED, 0x39, 0x32	//out0    (dcntl),a       ;0 mem, max i/0 wait states
};

const FLASH uint8_t sertest[] = {
	0xAF,              //  	xor	a
	0xED, 0x39, 0x36,  //  	out0	(rcr),a		;disable  DRAM refresh
	0x3E, 0x30,        //  	ld	a,030h
	0xED, 0x39, 0x32,  //  	out0	(dcntl),a	;0 mem, max i/0 wait states
	0x3E, 0x80,        //  	ld	a,M_MPBT		;no MP, PS=10, DR=16, SS=0
	0xED, 0x39, 0x03,  //  	out0	(cntlb1),a
	0x3E, 0x64,        //  	ld	a,M_RE + M_TE + M_MOD2	;
	0xED, 0x39, 0x01,  //  	out0	(cntla1),a
	0x3E, 0x00,        //  	ld	a,0
	0xED, 0x39, 0x05,  //  	out0	(stat1),a	;Enable rx interrupts
	0xED, 0x38, 0x05,  //l0:in0	a,(stat1)
	0xE6, 0x80,        //  	and	80h
	0x28, 0xF9,        //  	jr	z,l0
	0xED, 0x00, 0x09,  //  	in0	b,(rdr1)
	0xED, 0x38, 0x05,  //l1:in0	a,(stat1)
	0xE6, 0x02,        //  	and	02h
	0x28, 0xF9,        //  	jr	z,l1
	0xED, 0x01, 0x07,  //  	out0	(tdr1),b
	0x18, 0xEA,        //  	jr	l0
};

const FLASH uint8_t test1[] = {
	0xAF,              //	xor	a
	0xED, 0x39, 0x36,  //	out0	(rcr),a		;disable  DRAM refresh
	0x3E, 0x30,        //	ld	a,030h
	0xED, 0x39, 0x32,  //	out0	(dcntl),a	;0 mem, max i/0 wait states
	0x21, 0x1E, 0x00,  // 	ld	hl,dmclrt	;load DMA registers
	0x06, 0x08,        //	ld	b,dmct_e-dmclrt
	0x0E, 0x20,        //	ld	c,sar0l
	0xED, 0x93,        //	otimr
	0x3E, 0xC3,        //	ld	a,0c3h		;dst +1, src +1, burst
	0xED, 0x39, 0x31,  //	out0	(dmode),a	;
	0x3E, 0x62,        //	ld	a,062h		;enable dma0,
	0xED, 0x39, 0x30,  //cl_1:	out0	(dstat),a	;copy 64k
	0x18, 0xFB,        //	jr	cl_1		;
	0x00, 0x00,        //dmclrt:	dw	0		;src (inc)
	0x00,              //	db 	0		;src
	0x00, 0x00,        //	dw	0		;dst (inc),
	0x00,              //	db	0		;dst
	0x00, 0x00,        //	dw 	0		;count (64k)
};
#endif