#CDROM subroutine calls
8 messages in this thread
Bill -shareware. It's callable from C, Visual Basic, etc. and gives you a very
easy way to access CD-ROM audio and data.
Of course, for audio you can just use MCI, but I've found the MCI CD audio
driver to be incredibly slow and buggy (besides which, the interface is
TERRIBLE — all those God-awful bit flags and data structures).
I am still working on the data access portion. Let me know if you want any
more information.
–Mark O'Brien
I am trying to find out what the normal interface is. Would I normally
make int calls like I would for a mouse (via mscdex?). I wrote a message
here asking about cd+g and am looking into how I could read subcode
information.
Rick
There are two interfaces involved with MSCDEX:
1) The interface to MSCDEX itself (MSCDEX.EXE). This is by making int
calls, like for a mouse, except you call int 2f instead of int 33. There
are a number of int 2f function calls you can make to MSCDEX.
2) The interface to the MSCDEX device driver. An MSCDEX compatible CD-ROM
device driver is required to make a number of functions available via a
standard interface. This interface is how MSCDEX.EXE communicates with the
CD-ROM device driver. The specs for this interface are available from
Microsoft, and are online in the Microsoft section of CompuServe.
It is the device driver interface that contains the functions for reading
subcode that you would need to read the graphics from a CD+G disc. The
MSCDEX.EXE interface provides a function for passing a device driver
command to the CD-ROM device driver. It is recommended that you use the
MSCDEX call, rather than calling the CD-ROM device driver directly, for two
reasons: 1) Calling the device driver through MSCDEX is much easier than
calling the device driver directly. 2) Calling the device driver directly
can confuse MSCDEX.
Great info! I have been looking around the specs in the microsoft area but
cannot find them, and I have looked thru the MSL (lib area) with no
luck…. can you guide me further?
Rick
Mark – I suspect I may have missed an earlier message from you somehow. I
asked some time ago if there were standardized standards or possibly
packages to access CDROM data. In this message you say "it's callable from
C, . . . .and gives you a very easy way to access . . .". What is "IT"? A
package you are familiar with? You also reference MCI for audio access;
I'm such a neophyte in the CDROM world that the only MCI I recognize is the
telecommunications company! <g> What's MCI? Thanks, Bill
Bill -routines I wrote that provide access to CD-ROM at the MSCDEX/device driver
level. The routines are callable from C, Visual Basic, etc., via an SDK
that I am working on.
Let me know if you want any more info, including what sort of functionality
you would require.
MCI is Media Control Interface, the Microsoft layer which provides access
to multimedia devices like Wave audio, CD-ROM, MIDI…it's pretty bogus, in
my opinion.
–Mark
Bill -getting thrown away! That's why they seemed to be starting in midstream,
because they were.
I was talking about a CD-ROM SDK that I'm writing that gives access to data
and audio functions, callable from C, Visual Basic, etc. that is faster and
easier than MCI, which is Microsoft's way.
Let me know if you want any more information, including what functionality
you might want.
–Mark
Hi, Mark Mystifying why the two messages in the forum have missing stuff at
the start; I got the complete message via EMAIL. YES, I am definitely
interested in a SDK package that provides C-language access to the
device-driver level CDROM stuff. Do you have any idea when you would be
ready to release something, and about what it would cost? I'm really
asking more for my boss than myself; neither of us have actual CDROM
hardware yet but we are both about to buy same. He is interested in
language processing and accessing under his own program control some CDROMs
that have large amounts of textual information; like the packages of great
literature, for example. But he wants to read the data for computer
processing, rather than just display it as their bundled package does. I
don't think either of us have gotten far enough into the idea yet that we
could even give you a list of the desired C functions to be called; while
we are both expert C/Windows people, neither of us knows diddly about CDROM
yet!