Question on QNX devb driver development for CD-ROM

QNX DEVELOPERS Realtime and Embedded
1

Hi,

I am looking for some information regarding filesystem on QNX 6.2.1.

  1. I want to write a devb driver for CD-ROM. Can anyone give me the
    starting pointers?

  2. Is ISO-9660 natively supported by QNX?

regards,

Jagmohan

2

  1. I don’t remember devb is in the DDK source. Someone may correct me if I am wrong.

  2. Yes, ISO-9660 is natively supported.

3

There isn’t a block DDK. What CDROM are you trying to support that isn’t already support? :slight_smile:

4

Thanks for the replies.

Let me describe what I am doing.

I am building a MP3 player on an embedded system. The MP3 files
are stored on a CD-ROM. I need to read the directory of MP3 files
from CD-ROM. Using this need to read the MP3 files. The missing
piece in this is interface between ISO-9660 file system on QNX
and CD mechanism. This piece I think is the block device driver
for CD-ROM. Using this piece, I need to read the CD-ROM blocks
corresponding to directory or MP3 files. My view of the system looks
as below

±----------------------+
| QNX FILE SYSTEM |<------------------- Provides Generic APIs like
±---------±----------+ fread(), fopen() etc…
|
|
V
±---------±---------------+
| ISO 9660 FILE SYSTEM |<------------- Provides ISO 9660 specific
±---------±---------------+ functionality
|
|
V
±---------±---------------+
| Low Level Driver |<------------- Provides Block Read and decode
| devb-cdrom |
±---------±---------------+ functionality
|
|
V
±---------±---------------+
| CD Mechanism |
±---------±---------------+

Please correct me if my understanding is wrong.

regards,

Jagmohan

5

Are you sure that the ATA/IDE/ATAPI CDROM driver devb-eide doesn’t work with your cd-rom ?

6

If that doesn’t work you will need a good business case to present to QSS to get the info you need to write a driver.