Hi
Wie kann ich im DOS 6.22 zwischen einer eingelegten CD-ROM und einer DVD unterscheiden.
Gibt es da eine Interrupts Funktion von DOS (int 21h ) oder so um an Daten der Scheiben zu kommen.
Das mit den Ports krieg ich irgend wie nicht hin. ATAPI Ansteuerung Port 0x1F6 oder 0x170 brachte keine Daten.

BM

1. You can distinguish CD from DVD-ROM only by the passport "Identify Packet Device" command opcode = A1h.
2. If the interface is ATA, then ports 1F0h-170h (1f6 is the choice of the Master/Slave device).
3. If the interface is SATA, then the ports are different, and their numbers must be obtained from BAR[0:5] of the PCI space.
4. Show your code, how you request the passport.

MS-DOS has only FAT file system functions, while CD-ROM uses the CDFS (iso_9660) file system, and DVD uses UDF (universal disk format). Therefore, DOS cannot work with CD/DVD, and it needs an additional MSCDEX driver. If this driver is available, then simply specify the drive letter (for example E:\) and then the usual DOS read/write functions: AH=3Fh/40h int-21h.