magnetic field of Read Magnetic disc

Previous DOS edition to read, write, format the No. 0 track of the 1th magnetic field, the program is roughly as follows:

Char buffer[512];
reg.x.dx=0; /* for Drive A *
REG.X.CX=0X0001/* For boot sector * *
Reg.x.bx=fp_off (buffer);
SREG.ES=FP_SEG (buffer);
resg.x.ax=0x0201; /* For read, the for write, the for format */
int86x (0x13,&reg,&reg,&sreg);

then convert to call DeviceIoControl under Windows to format, read, and write to the magnetic track, dioc_registers this struct in DOS int21 for HDD or FDD parameters to format is int21 also have , but it is also available under Windows.


#pragma pack (push, 1)


struct Dioc_registers {


DWORD Reg_ebx;


DWORD Reg_edx;


DWORD Reg_ecx;


DWORD Reg_eax;


DWORD Reg_edi;


DWORD Reg_esi;


DWORD Reg_flags;


};


#pragma pack (POP)


Sdiskimageinfo->hdevice =:: CreateFile ("\\\\.\\vwin32", 0, 0, NULL, 0, file_flag_delete_on_close, NULL);


if (Sdiskimageinfo->hdevice = = Invalid_handle_value)


Brunnext = false;


//Reset floppy disk


reg.reg_ebx = 0;


reg.reg_eax = 0x0000; IOCTL for block devices


Reg.reg_edx = sdiskimageinfo->driver;


Reg.reg_edi = 0; reg.reg_esi= 0;


reg.reg_flags = 0x0001; Assume error (carry flag is set)


dwresult =::d Eviceiocontrol (Sdiskimageinfo->hdevice, vwin32_dioc_dos_int13, &reg, sizeof (dioc_registers ), &reg,


sizeof (dioc_registers), &CB, 0);


//Seek floppy


reg.reg_ebx = 0;


reg.reg_eax = 0x0c00; IOCTL for block devices


reg.reg_ecx = (sdiskimageinfo->nc << 8) | sdiskimageinfo->ns;


Reg.reg_edx = (sdiskimageinfo->nh << 8) | sdiskimageinfo->driver;


Reg.reg_edi = 0;


reg.reg_esi= 0;


Reg.reg_flags = 0x0001; Assume error (carry flag is set)


dwresult =::d Eviceiocontrol (Sdiskimageinfo->hdevice,


vwin32_dioc_dos_int13,


&reg, sizeof (dioc_registers), &reg,


sizeof (dioc_registers), &CB, 0);


//Read floppy


R_creatediskimagefile:


reg.reg_ebx = 0;


Reg.reg_eax = 0x0200 |　　　 0x01 IOCTL for block devices


reg.reg_ecx = (sdiskimageinfo->nc << 8) | sdiskimageinfo->ns;


Reg.reg_edx = (sdiskimageinfo->nh << 8) | sdiskimageinfo->driver;


REG.REG_EBX = (DWORD) &m_buf;


Reg.reg_edi = 0;


reg.reg_esi= 0;


reg.reg_flags = 0x0001; Assume error (carry flag is set)


dwresult =::d Eviceiocontrol (Hdevice, vwin32_dioc_dos_int13,


&reg, sizeof (dioc_registers), &reg,


sizeof (dioc_registers), &CB, 0);


if (!dwresult | | (Reg.reg_flags & 0x0001))


{


}