disabling SMI

I have a real-time app that runs on a P4. The box we are running it on
has an Aopen i865PEa-7IF motherboard. We are using the On-Time RTOS.
We have found that every 37 seconds the app completely stops running
for 250 microseconds. Using a PCI bus analyzer we discovered that
between the last operation done by my app and when my app resumes
running shows 100's and 100's of I/O reads and writes to addresses B3,
EB, and 61. Googling on this has led me to believe that these accesses
are related to SMI's and SMM. I have disabled everything in the BIOS -
USB, LAN, power management, serial and parallel ports, modem, firewire,
MIDI and game ports - yet my app still stops and I still see these
accesses.

Does anyone know how I can totally disable the SMI's?

TIA!
-larry

Richard wrote:
> <Larry.Martell DeleteThis @gmail.com> wrote in message
> news:1149202266.495177.211530@i40g2000cwc.googlegroups.com...
> >I have a real-time app that runs on a P4. The box we are running it on
> > has an Aopen i865PEa-7IF motherboard. We are using the On-Time RTOS.
> > We have found that every 37 seconds the app completely stops running
> > for 250 microseconds. Using a PCI bus analyzer we discovered that
> > between the last operation done by my app and when my app resumes
> > running shows 100's and 100's of I/O reads and writes to addresses B3,
> > EB, and 61. Googling on this has led me to believe that these accesses
> > are related to SMI's and SMM. I have disabled everything in the BIOS -
> > USB, LAN, power management, serial and parallel ports, modem, firewire,
> > MIDI and game ports - yet my app still stops and I still see these
> > accesses.
> >
> > Does anyone know how I can totally disable the SMI's?
>
> Are you using an Intel processor with this, or a compatible non Intel part?

I am using an Intel 3.6 GHz P4 (775 socket)

> I have experienced a similar problem when we switched components once, but I
> forget which (non Intel) part was giving us the grief. It turned out to be
> some silicon bug which had been mentioned on the On-Time support archive.
> Sorry my memory of it is too sketchy but I think there was some way of
> disabling the SMI in software during the start-up routine - but this then
> lead me to a different problem and in the end I just ditched the processor
> for a different variant.
>
> It might be that your problem is completely different but I suggest looking
> through the On-Time support archive for SMI or SMM. You should hit some
> info if you go back far enough.

I've been told this by others as well, but my searches in the archives
have not turned up any hits.

Thanks!
-larry