China DOS Union

Found some materials, all are in assembly, but I don't understand assembly. How to write it in C language? Thanks

One should know one's limits, and should not be overreaching!

Is the English of the 2nd floor very good? Translate some shares!

The following program is a small program I shrank from a CD player program a few years ago to open and close the CD drive, for you to play with. But there is a shortcoming, it can only run in pure DOS. When running in the DOS window of Win9x, if there is no disc in the CD drive, it cannot be opened, but it can be closed.

#include<dos.h>

int ppp=0;

unsigned int cdnum;

char getbuff,setbuff;

char  stop={0x0d,0,0x85,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

char setcd={0x1a,0,0x0c,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

char getcd={0x1a,0,0x03,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};



main()

{int i; char ch;

 _BX=0;

 _AX=0x1500;

 geninterrupt(0x2f);

 if(ppp==0){cdnum=_CX;ppp=1;}

 _AX=FP_OFF(getbuff);

 _BX=FP_SEG(getbuff);

 getcd=_AL;

 getcd=_AH;

 getcd=_BL;

 getcd=_BH;

 _AX=FP_OFF(setbuff);

 _BX=FP_SEG(setbuff);

 setcd=_AL;

 setcd=_AH;

 setcd=_BL;

 setcd=_BH;

 for(i=0;i<2;i++)

 {

  getcd=5;

  getbuff=0x06;

  _ES=FP_SEG(getcd);

  _BX=FP_OFF(getcd);

  _CX=cdnum;

  _AX=0x1510;

  geninterrupt(0x2f);

 }

 ch=getbuff&0x01;

 if(ch==0)i=0;

 else i=1;

 if(i==0)

 {_ES=FP_SEG(stop);  /*Stop CD*/

  _BX=FP_OFF(stop);

  _CX=cdnum;

  _AX=0x1510;

  geninterrupt(0x2f);

  setcd=1;     /*Open CD*/

  setbuff=0;

  _ES=FP_SEG(setcd);

  _BX=FP_OFF(setcd);

  _CX=cdnum;

  _AX=0x1510;

  geninterrupt(0x2f);

 }

 else

 {             /*Close CD*/

  setcd=1;

  setbuff=5;

  _ES=FP_SEG(setcd);

  _BX=FP_OFF(setcd);

  _CX=cdnum;

  _AX=0x1510;

  geninterrupt(0x2f);

 }

}

[ Last edited by JonePeng on 2006-5-1 at 00:48 ]

The following is the statement from zhaojinpo on 2004-8-19 22:22:40: You can see the introduction from http://www.he.net/~marcj/cdrom.html! The source code is at ftp://ftp.he.net/pub/marcj/cdrom.c

ftp://ftp.he.net/pub/marcj/cdrom.c I tried it, but there seems to be some problem. Why is there no reaction from the CD drive? It doesn't open, close, or read the disc! The LZ means to compile a program to open and close the CD drive, and the above C program I adapted works well. Rename the compiled EXE to EJ.EXE. Just press EJ and hit Enter under DOS to open the CD drive, and input again to close it. I always like to use it. ^_^

Yes, I used the file ftp://ftp.he.net/pub/marcj/cdrom.c, but it seems to be of no use and there's no response. The program on the 4th floor is pretty good, thank you.

I hope to use port programming instead of interrupts to write??

QCDROM "Assembly Language Master" (I said) produced, supports UltraDMA, quite stable, with SHSUCDX V3.03A (Jack R. Ellis modified version) is even more "fast"!

http://johnson.tmfc.net/freedos

There are QCDROM and SHCDX33A downloads!

[ Last edited by johnsonlam on 2006-4-24 at 11:40 ]

I want to ask about the statement of the moderator on the 4th floor:
for(i=0;i<2;i++) and ch=getbuff&0x01;
What is the function of i<, and it seems that lt, amp are not defined?

[ Last edited by qingfen on 2006-4-26 at 01:10 ]

Originally posted by qingfen at 2006-4-25 03:07:
for(i=0;i < 2;i++) and ch=getbuff & 0x01;
What is the function of i <, and it seems that lt and amp are not defined?

Previously, this forum was a DVBBS forum, which was particularly sensitive to the "&" and less-than symbols in the source code, turning "&" into "&amp" and less-than signs into "%lt" and so on. Now the source code on the 4th floor has been updated.

What is the principle of controlling the CD-ROM drive switch? Are all CD-ROM drives the same? Is there an introduction in some "XXX Interrupt Compendium"?

Oh, that's how it is. But how can Windows system be compatible with so many CD-ROM drives? And what's the difference between kernel drivers and device drivers?

Bend it yourself regarding ATAPI Spec