FDC Problem: read sector from disc
Posted: Fri Sep 03, 2004 5:29 pm
Hi,
the part of the floppy-driver works until it reaches the first read sector from, disc function. Seek and Specify work as expected, read sec.. returns no interrupt.
This is the used code:
The functions making problems:
Thank you, rumpel.
the part of the floppy-driver works until it reaches the first read sector from, disc function. Seek and Specify work as expected, read sec.. returns no interrupt.
This is the used code:
Code: Select all
typedef struct {
uchar head;
uchar track;
uchar sektor;
} disk_position_t;
void init_fdc(void)
{
fdc_reset();
fdc_recalibrate();
fdc_seek(1);
set_disk_position(1, &disk_pos);
if(!fdc_read_sektor(&disk_pos)) {
printf("Error: Can't read Sektor.\n");
}
}
void fdc_reset(void)
{
// reset
motoroff();
// select floppydrive
outb(FD_DOR, 0x1c);
// data rate: 500k/s
outb(FD_DRS, 0);
wait_fdc_irq(0);
// specify floppy type:
send_byte(FD_DATA, FD_SPECIFY);
send_byte(FD_DATA, 0xdf); //floppy_type.spec1);
send_byte(FD_DATA, 0x02); //floppy_type.spec2);
clear_floppy_irq();
}
uchar fdc_seek(uchar track)
{
send_byte(FD_DATA, FD_SEEK);
send_byte(FD_DATA, 0);
send_byte(FD_DATA, track);
wait_fdc_irq(1);
if((fdc_st0 != 0x20) || fdc_dp->track != track ) {
printf("Floppy Disk Controller: fdc_seek fehlgeschlagen. ST0 = %d", fdc_st0);
return(0);
} else {
return(1);
}
}
uchar fdc_recalibrate(void)
{
//motoron();
send_byte(FD_DATA, FD_CALIBRATE);
send_byte(FD_DATA, 0);
wait_fdc_irq(1);
//motoroff();
}
Code: Select all
void set_disk_position(int log_sek, disk_position_t *dp) // Logischer Sektor => CHS
{
dp->track = (log_sek / 18) / 2;
dp->head = (log_sek / 18) % 2;
dp->sektor = ((log_sek % 18)+1);
}
int fdc_read_sektor(disk_position_t *dp)
{
dma_block_t dma_block;
if(!fdc_seek(dp->track)) {
printf("fdc_read_sektor: fdc_seek returns error.\n");
return 0;
}
setup_dmablock(&dma_block, 0x40000, 0x200);
setup_dma(2, 0x46, &dma_block);
clear_floppy_irq();
send_byte(FD_DATA, 0xe6);
send_byte(FD_DATA, dp->head << 2);
send_byte(FD_DATA, dp->track);
send_byte(FD_DATA, dp->head);
send_byte(FD_DATA, dp->sektor);
send_byte(FD_DATA, 2); // sek = 512 Bytes
send_byte(FD_DATA, 18);
send_byte(FD_DATA, 0x1b);
send_byte(FD_DATA, 0xff);
fdc_st0 = 0xFF;
wait_fdc_irq(0);
if((fdc_st0 & 0xc0) != 0x00) {
printf("fdc_read_sektor: Error %d.\n", fdc_st0 & 0xc0);
return 0;
}
return 1;
}