QNX Boot Issues Caused by Industrial Grade Compact Flash
In late 2004, QNX boot issues when booting from industrial grade compact flash whereas the standard grade CF would work OK. It was determined that the newer industrial grade compact flash used DMA functions whereas our SBC boards did not support these signals.
Disabling DMA when booting QNX was a work-around to this issue. Later newer SBC's were designed to use these DMA signals thus fixing the issue.
To disable DMA (reported by a user):
The standard QNX install creates a .boot and a .altboot file. The documentation says that the only difference is that the .altboot disables DMA. Copy the .boot to a backup (to use DMA in the future), then copy the .altboot over the .boot.