gsplus/.svn/pristine/6c/6ceb07451a786a0f946287bde6e91bc0feb7e23c.svn-base
2015-11-05 14:23:46 -06:00

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/*
GSport - an Apple //gs Emulator
Copyright (C) 2010 - 2012 by GSport contributors
Based on the KEGS emulator written by and Copyright (C) 2003 Kent Dickey
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "defc.h"
extern int Verbose;
extern int Halt_on;
extern int g_rom_version;
extern int g_io_amt;
extern int g_highest_smartport_unit;
word32 g_cycs_in_io_read = 0;
extern Engine_reg engine;
extern Iwm iwm;
#define LEN_SMPT_LOG 16
STRUCT(Smpt_log) {
word32 start_addr;
int cmd;
int rts_addr;
int cmd_list;
int extras;
int unit;
int buf;
int blk;
};
Smpt_log g_smpt_log[LEN_SMPT_LOG];
int g_smpt_log_pos = 0;
void
smartport_error(void)
{
int pos;
int i;
pos = g_smpt_log_pos;
printf("Smartport log pos: %d\n", pos);
for(i = 0; i < LEN_SMPT_LOG; i++) {
pos--;
if(pos < 0) {
pos = LEN_SMPT_LOG - 1;
}
printf("%d:%d: t:%04x, cmd:%02x, rts:%04x, "
"cmd_l:%04x, x:%d, unit:%d, buf:%04x, blk:%04x\n",
i, pos,
g_smpt_log[pos].start_addr,
g_smpt_log[pos].cmd,
g_smpt_log[pos].rts_addr,
g_smpt_log[pos].cmd_list,
g_smpt_log[pos].extras,
g_smpt_log[pos].unit,
g_smpt_log[pos].buf,
g_smpt_log[pos].blk);
}
}
void
smartport_log(word32 start_addr, int cmd, int rts_addr, int cmd_list)
{
int pos;
pos = g_smpt_log_pos;
if(start_addr != 0) {
g_smpt_log[pos].start_addr = start_addr;
g_smpt_log[pos].cmd = cmd;
g_smpt_log[pos].rts_addr = rts_addr;
g_smpt_log[pos].cmd_list = cmd_list;
g_smpt_log[pos].extras = 0;
g_smpt_log[pos].unit = 0;
g_smpt_log[pos].buf = 0;
g_smpt_log[pos].blk = 0;
} else {
pos--;
if(pos < 0) {
pos = LEN_SMPT_LOG - 1;
}
g_smpt_log[pos].extras = 1;
g_smpt_log[pos].unit = cmd;
g_smpt_log[pos].buf = rts_addr;
g_smpt_log[pos].blk = cmd_list;
}
pos++;
if(pos >= LEN_SMPT_LOG) {
pos = 0;
}
g_smpt_log_pos = pos;
}
void
do_c70d(word32 arg0)
{
int cmd;
int cmd_list_lo, cmd_list_mid, cmd_list_hi;
int rts_lo, rts_hi;
word32 rts_addr;
word32 cmd_list;
int unit;
int param_cnt;
int status_ptr_lo, status_ptr_mid, status_ptr_hi;
int buf_ptr_lo, buf_ptr_hi;
int buf_ptr;
int block_lo, block_mid, block_hi;
int block;
word32 status_ptr;
int status_code;
int ctl_ptr_lo, ctl_ptr_hi;
int ctl_ptr;
int ctl_code;
int mask;
int stat_val;
int size;
int ret;
int ext;
int i;
set_memory_c(0x7f8, 0xc7, 0);
if((engine.psr & 0x100) == 0) {
disk_printf("c70d called in native mode!\n");
if((engine.psr & 0x30) != 0x30) {
halt_printf("c70d called native, psr: %03x!\n",
engine.psr);
}
}
engine.stack = ((engine.stack + 1) & 0xff) + 0x100;
rts_lo = get_memory_c(engine.stack, 0);
engine.stack = ((engine.stack + 1) & 0xff) + 0x100;
rts_hi = get_memory_c(engine.stack, 0);
rts_addr = (rts_lo + (256*rts_hi) + 1) & 0xffff;
disk_printf("rts_addr: %04x\n", rts_addr);
cmd = get_memory_c(rts_addr, 0);
cmd_list_lo = get_memory_c((rts_addr + 1) & 0xffff, 0);
cmd_list_mid = get_memory_c((rts_addr + 2) & 0xffff, 0);
cmd_list_hi = 0;
mask = 0xffff;
if(cmd & 0x40) {
/* extended */
mask = 0xffffff;
cmd_list_hi = get_memory_c((rts_addr + 3) & 0xffff, 0);
}
cmd_list = cmd_list_lo + (256*cmd_list_mid) + (65536*cmd_list_hi);
disk_printf("cmd: %02x, cmd_list: %06x\n", cmd, cmd_list);
param_cnt = get_memory_c(cmd_list, 0);
ext = 0;
if(cmd & 0x40) {
ext = 2;
}
smartport_log(0xc70d, cmd, rts_addr, cmd_list);
switch(cmd & 0x3f) {
case 0x00: /* Status == 0x00 and 0x40 */
if(param_cnt != 3) {
disk_printf("param_cnt %d is != 3!\n", param_cnt);
exit(8);
}
unit = get_memory_c((cmd_list+1) & mask, 0);
status_ptr_lo = get_memory_c((cmd_list+2) & mask, 0);
status_ptr_mid = get_memory_c((cmd_list+3) & mask, 0);
status_ptr_hi = 0;
if(cmd & 0x40) {
status_ptr_hi = get_memory_c((cmd_list+4) & mask, 0);
}
status_ptr = status_ptr_lo + (256*status_ptr_mid) +
(65536*status_ptr_hi);
if(cmd & 0x40) {
status_code = get_memory_c((cmd_list+6) & mask, 0);
} else {
status_code = get_memory_c((cmd_list+4) & mask, 0);
}
smartport_log(0, unit, status_ptr, status_code);
disk_printf("unit: %02x, status_ptr: %06x, code: %02x\n",
unit, status_ptr, status_code);
if(unit == 0 && status_code == 0) {
/* Smartport driver status */
/* see technotes/smpt/tn-smpt-002 */
set_memory_c(status_ptr, g_highest_smartport_unit+1, 0);
set_memory_c(status_ptr+1, 0xff, 0); /* interrupt stat*/
set_memory16_c(status_ptr+2, 0x0002, 0); /* vendor id */
set_memory16_c(status_ptr+4, 0x1000, 0); /* version */
set_memory16_c(status_ptr+6, 0x0000, 0);
engine.xreg = 8;
engine.yreg = 0;
engine.acc &= 0xff00;
engine.psr &= ~1;
engine.kpc = (rts_addr + 3 + ext) & mask;
return;
} else if(unit > 0 && status_code == 0) {
/* status for unit x */
if(unit > MAX_C7_DISKS || (!iwm.smartport[unit-1].file)){
stat_val = 0x80;
size = 0;
} else {
stat_val = 0xf8;
size = iwm.smartport[unit-1].image_size;
size = (size+511) / 512;
}
set_memory_c(status_ptr, stat_val, 0);
set_memory24_c(status_ptr +1, size, 0);
engine.xreg = 4;
if(cmd & 0x40) {
set_memory_c(status_ptr + 4,
(size >> 16) & 0xff, 0);
engine.xreg = 5;
}
engine.yreg = 0;
engine.acc &= 0xff00;
engine.psr &= ~1;
engine.kpc = (rts_addr + 3 + ext) & mask;
disk_printf("just finished unit %d, stat 0\n", unit);
return;
} else if(status_code == 3) {
if(unit > MAX_C7_DISKS || (!iwm.smartport[unit-1].file)){
stat_val = 0x80;
size = 0;
} else {
stat_val = 0xf8;
size = iwm.smartport[unit-1].image_size;
size = (size+511) / 512;
}
if(cmd & 0x40) {
disk_printf("extended for stat_code 3!\n");
}
/* DIB for unit 1 */
set_memory_c(status_ptr, stat_val, 0);
set_memory24_c(status_ptr +1, size, 0);
if(cmd & 0x40) {
set_memory_c(status_ptr + 4,
(size >> 24) & 0xff, 0);
status_ptr++;
}
set_memory_c(status_ptr +4, 4, 0);
for(i = 5; i < 21; i++) {
set_memory_c(status_ptr +i, 0x20, 0);
}
set_memory_c(status_ptr +5, 'K', 0);
set_memory_c(status_ptr +6, 'E', 0);
set_memory_c(status_ptr +7, 'G', 0);
set_memory_c(status_ptr +8, 'S', 0);
/* hard disk supporting extended calls */
set_memory16_c(status_ptr + 21, 0xa002, 0);
set_memory16_c(status_ptr + 23, 0x0000, 0);
if(cmd & 0x40) {
engine.xreg = 26;
} else {
engine.xreg = 25;
}
engine.yreg = 0;
engine.acc &= 0xff00;
engine.psr &= ~1;
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
disk_printf("Just finished unit %d, stat 3\n", unit);
if(unit == 0 || unit > MAX_C7_DISKS) {
engine.acc |= 0x28;
engine.psr |= 1;
}
return;
}
printf("cmd: 00, unknown unit/status code!\n");
break;
case 0x01: /* Read Block == 0x01 and 0x41 */
if(param_cnt != 3) {
halt_printf("param_cnt %d is != 3!\n", param_cnt);
return;
}
unit = get_memory_c((cmd_list+1) & mask, 0);
buf_ptr_lo = get_memory_c((cmd_list+2) & mask, 0);
buf_ptr_hi = get_memory_c((cmd_list+3) & mask, 0);
buf_ptr = buf_ptr_lo + (256*buf_ptr_hi);
if(cmd & 0x40) {
buf_ptr_lo = get_memory_c((cmd_list+4) & mask, 0);
buf_ptr_hi = get_memory_c((cmd_list+5) & mask, 0);
buf_ptr += ((buf_ptr_hi*256) + buf_ptr_lo)*65536;
cmd_list += 2;
}
block_lo = get_memory_c((cmd_list+4) & mask, 0);
block_mid = get_memory_c((cmd_list+5) & mask, 0);
block_hi = get_memory_c((cmd_list+6) & mask, 0);
block = ((block_hi*256) + block_mid)*256 + block_lo;
disk_printf("smartport read unit %d of block %04x into %04x\n",
unit, block, buf_ptr);
if(unit < 1 || unit > MAX_C7_DISKS) {
halt_printf("Unknown unit #: %d\n", unit);
}
smartport_log(0, unit - 1, buf_ptr, block);
ret = do_read_c7(unit - 1, buf_ptr, block);
engine.xreg = 0;
engine.yreg = 2;
engine.acc = (engine.acc & 0xff00) | (ret & 0xff);
engine.psr &= ~1;
if(ret != 0) {
engine.psr |= 1;
}
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
return;
break;
case 0x02: /* Write Block == 0x02 and 0x42 */
if(param_cnt != 3) {
halt_printf("param_cnt %d is != 3!\n", param_cnt);
return;
}
unit = get_memory_c((cmd_list+1) & mask, 0);
buf_ptr_lo = get_memory_c((cmd_list+2) & mask, 0);
buf_ptr_hi = get_memory_c((cmd_list+3) & mask, 0);
buf_ptr = buf_ptr_lo + (256*buf_ptr_hi);
if(cmd & 0x40) {
buf_ptr_lo = get_memory_c((cmd_list+4) & mask, 0);
buf_ptr_hi = get_memory_c((cmd_list+5) & mask, 0);
buf_ptr += ((buf_ptr_hi*256) + buf_ptr_lo)*65536;
cmd_list += 2;
}
block_lo = get_memory_c((cmd_list+4) & mask, 0);
block_mid = get_memory_c((cmd_list+5) & mask, 0);
block_hi = get_memory_c((cmd_list+6) & mask, 0);
block = ((block_hi*256) + block_mid)*256 + block_lo;
disk_printf("smartport write unit %d of block %04x from %04x\n",
unit, block, buf_ptr);
if(unit < 1 || unit > MAX_C7_DISKS) {
halt_printf("Unknown unit #: %d\n", unit);
}
smartport_log(0, unit - 1, buf_ptr, block);
ret = do_write_c7(unit - 1, buf_ptr, block);
engine.xreg = 0;
engine.yreg = 2;
engine.acc = (engine.acc & 0xff00) | (ret & 0xff);
engine.psr &= ~1;
if(ret != 0) {
engine.psr |= 1;
}
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
HALT_ON(HALT_ON_C70D_WRITES, "c70d Write done\n");
return;
break;
case 0x03: /* Format == 0x03 and 0x43 */
if(param_cnt != 1) {
halt_printf("param_cnt %d is != 1!\n", param_cnt);
return;
}
unit = get_memory_c((cmd_list+1) & mask, 0);
if(unit < 1 || unit > MAX_C7_DISKS) {
halt_printf("Unknown unit #: %d\n", unit);
}
smartport_log(0, unit - 1, 0, 0);
ret = do_format_c7(unit - 1);
engine.xreg = 0;
engine.yreg = 2;
engine.acc = (engine.acc & 0xff00) | (ret & 0xff);
engine.psr &= ~1;
if(ret != 0) {
engine.psr |= 1;
}
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
HALT_ON(HALT_ON_C70D_WRITES, "c70d Format done\n");
return;
break;
case 0x04: /* Control == 0x04 and 0x44 */
if(cmd == 0x44) {
halt_printf("smartport code 0x44 not supported\n");
}
if(param_cnt != 3) {
halt_printf("param_cnt %d is != 3!\n", param_cnt);
return;
}
unit = get_memory_c((cmd_list+1) & mask, 0);
ctl_ptr_lo = get_memory_c((cmd_list+2) & mask, 0);
ctl_ptr_hi = get_memory_c((cmd_list+3) & mask, 0);
ctl_ptr = (ctl_ptr_hi << 8) + ctl_ptr_lo;
if(cmd & 0x40) {
ctl_ptr_lo = get_memory_c((cmd_list+4) & mask, 0);
ctl_ptr_hi = get_memory_c((cmd_list+5) & mask, 0);
ctl_ptr += ((ctl_ptr_hi << 8) + ctl_ptr_lo) << 16;
cmd_list += 2;
}
ctl_code = get_memory_c((cmd_list +4) & mask, 0);
switch(ctl_code) {
case 0x00:
printf("Performing a reset on unit %d\n", unit);
break;
default:
halt_printf("control code: %02x unknown!\n", ctl_code);
}
engine.xreg = 0;
engine.yreg = 2;
engine.acc &= 0xff00;
engine.psr &= ~1;
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
return;
break;
default: /* Unknown command! */
/* set acc = 1, and set carry, and set kpc */
engine.xreg = (rts_addr) & 0xff;
engine.yreg = (rts_addr >> 8) & 0xff;
engine.acc = (engine.acc & 0xff00) + 0x01;
engine.psr |= 0x01; /* set carry */
engine.kpc = (rts_addr + 3 + ext) & 0xffff;
if(cmd != 0x4a && cmd != 0x48) {
/* Finder does 0x4a call before formatting disk */
/* Many things do 0x48 call to see online drives */
halt_printf("Just did smtport cmd:%02x rts_addr:%04x, "
"cmdlst:%06x\n", cmd, rts_addr, cmd_list);
}
return;
}
halt_printf("Unknown smtport cmd:%02x, cmd_list:%06x, rts_addr:%06x\n",
cmd, cmd_list, rts_addr);
}
void
do_c70a(word32 arg0)
{
int cmd, unit;
int buf_lo, buf_hi;
int blk_lo, blk_hi;
int blk, buf;
int prodos_unit;
int size;
int ret;
set_memory_c(0x7f8, 0xc7, 0);
cmd = get_memory_c((engine.direct + 0x42) & 0xffff, 0);
prodos_unit = get_memory_c((engine.direct + 0x43) & 0xffff, 0);
buf_lo = get_memory_c((engine.direct + 0x44) & 0xffff, 0);
buf_hi = get_memory_c((engine.direct + 0x45) & 0xffff, 0);
blk_lo = get_memory_c((engine.direct + 0x46) & 0xffff, 0);
blk_hi = get_memory_c((engine.direct + 0x47) & 0xffff, 0);
blk = (blk_hi << 8) + blk_lo;
buf = (buf_hi << 8) + buf_lo;
disk_printf("cmd: %02x, pro_unit: %02x, buf: %04x, blk: %04x\n",
cmd, prodos_unit, buf, blk);
if((prodos_unit & 0x7f) == 0x70) {
unit = 0 + (prodos_unit >> 7);
} else if((prodos_unit & 0x7f) == 0x40) {
unit = 2 + (prodos_unit >> 7);
} else {
halt_printf("Unknown prodos_unit: %d\n", prodos_unit);
return;
}
smartport_log(0xc70a, cmd, blk, buf);
engine.psr &= ~1; /* clear carry */
if(g_rom_version >= 3) {
engine.kpc = 0xc764;
} else {
engine.kpc = 0xc765;
}
ret = 0x27; /* I/O error */
if(cmd == 0x00) {
size = iwm.smartport[unit].image_size;
size = (size+511) / 512;
smartport_log(0, unit, size, 0);
ret = 0;
engine.xreg = size & 0xff;
engine.yreg = size >> 8;
} else if(cmd == 0x01) {
smartport_log(0, unit, buf, blk);
ret = do_read_c7(unit, buf, blk);
} else if(cmd == 0x02) {
smartport_log(0, unit, buf, blk);
ret = do_write_c7(unit, buf, blk);
} else if(cmd == 0x03) { /* format */
smartport_log(0, unit, buf, blk);
ret = do_format_c7(unit);
}
engine.acc = (engine.acc & 0xff00) | (ret & 0xff);
if(ret != 0) {
engine.psr |= 1;
}
return;
}
int
do_read_c7(int unit_num, word32 buf, int blk)
{
byte local_buf[0x200];
register word32 start_time;
register word32 end_time;
word32 val;
FILE *file;
int len;
int image_start;
int image_size;
int ret;
int i;
if(unit_num < 0 || unit_num > MAX_C7_DISKS) {
halt_printf("do_read_c7: unit_num: %d\n", unit_num);
smartport_error();
return 0x28;
}
file = iwm.smartport[unit_num].file;
image_start = iwm.smartport[unit_num].image_start;
image_size = iwm.smartport[unit_num].image_size;
if(!file) {
printf("c7_file is null!\n");
#if 0
if(blk != 2 && blk != 0) {
/* don't print error if only reading directory */
smartport_error();
halt_printf("Read unit:%02x blk:%04x\n", unit_num, blk);
}
#endif
return 0x2f;
}
ret = fseek(file, image_start + blk*0x200, SEEK_SET);
if(ret != 0) {
halt_printf("fseek errno: %d\n", errno);
smartport_error();
return 0x27;
}
if(image_start + blk*0x200 > image_start + image_size) {
halt_printf("Tried to read from pos %08x on disk, (blk:%04x)\n",
image_start + blk*0x200, blk);
smartport_error();
return 0x27;
}
len = fread(&local_buf[0], 1, 0x200, file);
if(len != 0x200) {
printf("fread returned %08x, errno:%d, blk:%04x, unit: %02x\n",
len, errno, blk, unit_num);
halt_printf("name: %s\n", iwm.smartport[unit_num].name_ptr);
smartport_error();
return 0x27;
}
g_io_amt += 0x200;
if(buf >= 0xfc0000) {
disk_printf("reading into ROM, just returning\n");
return 0;
}
GET_ITIMER(start_time);
for(i = 0; i < 0x200; i += 2) {
val = (local_buf[i+1] << 8) + local_buf[i];
set_memory16_c(buf + i, val, 0);
}
GET_ITIMER(end_time);
g_cycs_in_io_read += (end_time - start_time);
return 0;
}
int
do_write_c7(int unit_num, word32 buf, int blk)
{
word32 local_buf[0x200/4];
Disk *dsk;
word32 *ptr;
word32 val1, val2;
word32 val;
FILE *file;
int len;
int ret;
int image_start;
int image_size;
int i;
if(unit_num < 0 || unit_num > MAX_C7_DISKS) {
halt_printf("do_write_c7: unit_num: %d\n", unit_num);
smartport_error();
return 0x28;
}
dsk = &(iwm.smartport[unit_num]);
file = dsk->file;
image_start = dsk->image_start;
image_size = dsk->image_size;
if(!file) {
halt_printf("c7_file is null!\n");
smartport_error();
return 0x28;
}
ptr = &(local_buf[0]);
for(i = 0; i < 0x200; i += 4) {
val1 = get_memory16_c(buf + i, 0);
val2 = get_memory16_c(buf + i + 2, 0);
/* reorder the little-endian bytes to be big-endian */
#if defined(GSPORT_LITTLE_ENDIAN) || defined (__LITTLE_ENDIAN__) // OSX needs to calculate endianness mid-compilation, can't be passed on compile command
val = (val2 << 16) + val1;
#else
val = (val1 << 24) + ((val1 << 8) & 0xff0000) +
((val2 << 8) & 0xff00) + (val2 >> 8);
#endif
*ptr++ = val;
}
ret = fseek(file, image_start + blk*0x200, SEEK_SET);
if(ret != 0) {
halt_printf("fseek errno: %d\n", errno);
smartport_error();
return 0x27;
}
if(image_start + blk*0x200 > image_start + image_size) {
halt_printf("Tried to write to %08x\n", ret);
smartport_error();
return 0x27;
}
if(dsk->write_prot) {
printf("Write, but %s is write protected!\n", dsk->name_ptr);
return 0x2b;
}
if(dsk->write_through_to_unix == 0) {
halt_printf("Write to %s, but not wr_thru!\n", dsk->name_ptr);
return 0x00;
}
len = fwrite((byte *)&local_buf[0], 1, 0x200, file);
if(len != 0x200) {
halt_printf("fwrite ret %08x bytes, errno: %d\n", len, errno);
smartport_error();
return 0x27;
}
g_io_amt += 0x200;
return 0;
}
int
do_format_c7(int unit_num)
{
byte local_buf[0x1000];
Disk *dsk;
FILE *file;
int len;
int ret;
int sum;
int total;
int max;
int image_start;
int image_size;
int i;
if(unit_num < 0 || unit_num > MAX_C7_DISKS) {
halt_printf("do_format_c7: unit_num: %d\n", unit_num);
smartport_error();
return 0x28;
}
dsk = &(iwm.smartport[unit_num]);
file = dsk->file;
image_start = dsk->image_start;
image_size = dsk->image_size;
if(!file) {
halt_printf("c7_file is null!\n");
smartport_error();
return 0x28;
}
for(i = 0; i < 0x1000; i++) {
local_buf[i] = 0;
}
ret = fseek(file, image_start, SEEK_SET);
if(ret != 0) {
halt_printf("fseek errno: %d\n", errno);
smartport_error();
return 0x27;
}
if(dsk->write_prot) {
printf("Format, but %s is write protected!\n", dsk->name_ptr);
return 0x2b;
}
if(dsk->write_through_to_unix == 0) {
printf("Format of %s ignored\n", dsk->name_ptr);
return 0x00;
}
sum = 0;
total = image_size;
while(sum < total) {
max = MIN(0x1000, total-sum);
len = fwrite(&local_buf[0], 1, max, file);
if(len != max) {
halt_printf("write ret %08x, errno:%d\n", len, errno);
smartport_error();
return 0x27;
}
sum += len;
}
return 0;
}
extern byte g_bram[2][256];
extern byte* g_bram_ptr;
extern byte g_temp_boot_slot;
extern byte g_orig_boot_slot;
extern int g_config_gsport_update_needed;
void
do_c700(word32 ret)
{
disk_printf("do_c700 called, ret: %08x\n", ret);
if (g_temp_boot_slot != 254) {
// Booting from slot 7 - now is a good time to turn off the temp boot slot, if it was on.
g_temp_boot_slot = 254;
g_bram_ptr[40] = g_orig_boot_slot;
clk_calculate_bram_checksum();
g_config_gsport_update_needed = 1;
}
ret = do_read_c7(0, 0x800, 0);
set_memory_c(0x7f8, 7, 0);
set_memory16_c(0x42, 0x7001, 0);
set_memory16_c(0x44, 0x0800, 0);
set_memory16_c(0x46, 0x0000, 0);
engine.xreg = 0x70;
engine.kpc = 0x801;
if(ret != 0) {
printf("Failure reading boot disk in s7d1!\n");
engine.kpc = 0xff59; /* Jump to monitor, fix $36-$39 */
}
}