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QNX RTOS v4 Knowledge Base

Foundry27
Foundry27
QNX RTOS v4 project
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QNX RTOS v4 Knowledge Base

Title Installing QNX4 on an Enhanced IDE drive
Ref. No. QNX.000009300
Category(ies) Installation, Configuration
Issue We just bought a new PC with an Enhance IDE (EIDE) drive.  We want to run DOS and QNX4.11 on this machine, but QNX4.11 doesn't seem to recognize the drive after we install DOS.



Solution Extended IDE drives support Logical Block Addressing (LBA) functions and are marketed for systems (e.g. DOS) that have LBA support in the BIOS. QNX doesn't use the BIOS and that's why it seems unable to recognize your drive.

This can be solved in one of two ways.  The first option is to upgrade to QNX4.22, which comes with a new disk driver called Fsys.ata.  With Fsys.ata, it's possible to install QNX and still leave LBA enabled for DOS.
 
The other option is to stay with QNX4.11 and disable LBA mode in the CMOS configuration.  The method for doing this varies with each CMOS.  See the CMOS documentation that came with the motherboard for information on how to disable LBA.

For most systems, select the user-defined drive type and pass the physical parameters of the drive.  (If you've already installed DOS, you'll have to remove the DOS partition, reconfigure the CMOS, then reinstall DOS.)  You then install QNX, using the QNX install program's -p option to specify the drive's parameters.

When setting up your partition table, remember that the DOS partition must reside completely within the 1024 cylinder boundary, and that the QNX boot image must also reside within this boundary, otherwise you won't be able to boot.  Here's a sample partition table from a 540MB EIDE drive on which DOS and QNX have been installed:

x09-OS-x09x09Startx09Endx09-Number-x09x09Sizex09Boot
x09namex09typex09Cylinderx09Cylinderx09Cylindersx09Blocks

1.x09DOSx09( 6 )x090x09400x09401x09378544x09190 MB
2.x09ONXx09( 77 )x09405x091119x09715x09674960x09338 MB
3.x09ONYx09( 78 )x09401x09404x094x093776x092 MBx09*
4.x09...x09(---)x09....x09....x09....x09....x09.......x09....

x09heads = 16
x09cylinders = 1120
x09sectors/track = 59

To ensure the location of the QNX boot image on any large hard drive, you should make a small (2M) bootable partition on the first part of the disk, as the above example demonstrates.  For more information, see the QNX 4.22 readme file (/etc/readme/qnx422).