How to *not* start photon and other hardware drivers?

QNX Newsgroups (Archives) qnx.newuser
1

Hi,

I am trying to reduce the uncessary processes runing the QNX 6.3
system. I have a few question.

  1. How can I enter text mode only, without Photon? Currently the
    system starts Photon automatically after reboots.

  2. How can I not loading certain hardware drivers after reboots? For
    example,
    a. io-audio, : audio
    b. devc-ser8250:
    c. devc-par : Parallel port manager
    d. devb-fdc : floppy
    e. spooler : printer?

  3. How can I change timer interrupt priority? In both command line and
    codes.
    I assume the timer interrupt has priority of 0, the lowest one?

Thanks!

Iris

2

yyd_iris <yyd_iris@yahoo-dot-com.no-spam.invalid> wrote:

Hi,

I am trying to reduce the uncessary processes runing the QNX 6.3
system. I have a few question.

  1. How can I enter text mode only, without Photon? Currently the
    system starts Photon automatically after reboots.

Just create /etc/system/config/nophoton on your machine. It can be an
empty file:

touch /etc/system/config/nophoton

  1. How can I not loading certain hardware drivers after reboots? For
    example,
    a. io-audio, : audio
    b. devc-ser8250:
    c. devc-par : Parallel port manager
    d. devb-fdc : floppy
    e. spooler : printer?

If you’re using diskboot, a lot of the device detection takes place
automatically. You can add an /etc/system/enum/overrides file to
change this. You can also use a buildfile to specify exactly how you
want your machine to start. See the Controlling How Neutrino Starts
chapter of the Neutrino User’s Guide, as well as the Building Embedded
Systems guide.

  1. How can I change timer interrupt priority? In both command line and
    codes.
    I assume the timer interrupt has priority of 0, the lowest one?

Someone else will have to help you with this question.

\

Steve Reid stever@qnx.com
Technical Editor
QNX Software Systems

3

My recollection of the interrupt controllers is that you choose one
interrupt to have the highest priority, and the rest are in line.
The timer interrupt is interrupt 0, are you confused about this? I
also suspect that it has the highest priority by default.
There is some potential for confusion related to the fact that there
are two interrupt controllers. The one that handles interrupts
8-15 (the slave) is chained into interrupt 2 the master. Both of
these can have their interrupt priorities set. You can see however
that with
interrupt 0 being the highest on the master, interrupts 8-15 will be
higher than 3-7.

QNX 4 used to have a proc parameter to set these. I don’t how or if
QNX 6 lets you do it.

4

maschoen <maschoen@pobox-dot-com.no-spam.invalid> wrote:

My recollection of the interrupt controllers is that you choose one
interrupt to have the highest priority, and the rest are in line.
The timer interrupt is interrupt 0, are you confused about this? I
also suspect that it has the highest priority by default.

This is correct. (While under QNX 4, interrupt 3 was highest by
default.)

QNX 4 used to have a proc parameter to set these. I don’t how or if
QNX 6 lets you do it.

startup-bios has the (not yet documented) -I option to set it.

-David Gibbs

David Gibbs
QNX Training Services
dagibbs@qnx.com