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#include "monitor.h"
#ifdef MINI_BUF
#ifndef MAXTRK
#define MAXTRK 21
#endif
int disk_drive = 0;
int disk_spt = 7;
int disk_heads = 0;
int disk_cyls = 0;
int bad_track = -1;
static int track_no = -1;
static int buf_len = 0;
static char buffer[MAXTRK*512];
void reset_disk()
{
disk_spt = 7;
disk_heads = 0;
disk_cyls = 0;
bad_track = -1;
}
char * read_lsector(sectno)
long sectno;
{
int tries = 5;
int rv = 0;
int phy_s = 1;
int phy_h = 0;
int phy_c = 0;
int ltrack;
if( sectno == 0 ) reset_disk();
if( buf_len != disk_spt ) track_no = -1;
if( disk_spt < 1 || disk_heads < 1 )
phy_s = sectno;
else
{
phy_s = sectno%disk_spt;
phy_h = sectno/disk_spt%disk_heads;
phy_c = sectno/disk_spt/disk_heads;
}
#ifdef DEBUG
fprintf(stderr, "read_sector(%ld = %d,%d,%d)\n", sectno, phy_c, phy_h, phy_s);
#endif
ltrack = phy_c*disk_heads+phy_h;
if( disk_spt > 1 && disk_spt <= MAXTRK
&& track_no != ltrack && ltrack != bad_track)
{
rv = phy_read(disk_drive, phy_c, phy_h, 1, disk_spt, buffer);
if( rv == 0 )
{
track_no = ltrack;
buf_len = disk_spt;
}
else
bad_track = ltrack;
}
if( track_no == ltrack )
return buffer + phy_s * 512;
do
{
rv = phy_read(disk_drive, phy_c, phy_h, phy_s+1, 1, buffer);
tries--;
}
while(rv && tries > 0);
if( rv ) printf("Disk error 0x%02x %d:%d:%d:%d[%2d] -> 0x%04x[]\n",
rv, disk_drive, phy_c, phy_h, phy_s+1, 1, buffer);
if(rv) return 0; else return buffer;
}
#if defined(__MSDOS__) || defined(__STANDALONE__)
phy_read(drive, cyl, head, sect, length, buffer)
{
#asm
push bp
mov bp,sp
push ds
pop es
mov dl,[bp+2+_phy_read.drive]
mov ch,[bp+2+_phy_read.cyl]
mov dh,[bp+2+_phy_read.head]
mov cl,[bp+2+_phy_read.sect]
mov al,[bp+2+_phy_read.length]
mov bx,[bp+2+_phy_read.buffer]
mov ah,#$02
int $13
jc read_err
mov ax,#0
read_err:
pop bp
#endasm
}
#endif
#endif
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