Need access to CRTC registers!

HI, I need to access the CRTC registers on an nvidia card. It's a
SECONDARY card, so it doesnt have the CRTC registers at the usual
$03D4/$03D5 I/O ports. They're somewhere in the MMIO space. This is
on Windows XP.

Anybody have any info on how to get to them?

Code, drivers, API's?


Thanks,

George

Ancient_Hacker wrote:
HI, I need to access the CRTC registers on an nvidia card. It's a
SECONDARY card, so it doesnt have the CRTC registers at the usual
$03D4/$03D5 I/O ports. They're somewhere in the MMIO space. This is
on Windows XP.

Anybody have any info on how to get to them?

Code, drivers, API's?

What are you doing that needs access to those? Unless you're writing a
kernel driver, you're not going to able to access them anyway, wherever
they are.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from
Home Page: http://www.roberthancock.com/

I need to change the sync pulse widths to be much narrower, like zero
width.
Very easy to do, they're simple CRTC registers.

I already have access to the card's memory area-- I just need to know
exactly where they are in there.

Ancient_Hacker wrote:
I need to change the sync pulse widths to be much narrower, like zero
width.
Very easy to do, they're simple CRTC registers.

I already have access to the card's memory area-- I just need to know
exactly where they are in there.

I would be rather surprised if that info were publicly available. Your
best bet might be to look at the source code of the "nv" driver used in
the X.org X server in Linux, that MIGHT have some code to access those.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from
Home Page: http://www.roberthancock.com/

"Ancient_Hacker" wrote in message
oups.com...
HI, I need to access the CRTC registers on an nvidia card. It's a
SECONDARY card, so it doesnt have the CRTC registers at the usual
$03D4/$03D5 I/O ports. They're somewhere in the MMIO space. This is
on Windows XP.

Anybody have any info on how to get to them?

Code, drivers, API's?

In the Device Manager the resource information shown for each card would be
structured the same; so, given that $03D4 is at a particular offset within
one of the I/O ranges shown for the first card, you then just add that same
offset to its twin I/O range shown for the secondary card.

Tony.

The Black Wibble wrote:
"Ancient_Hacker" wrote in message
oups.com...

HI, I need to access the CRTC registers on an nvidia card. It's a
SECONDARY card, so it doesnt have the CRTC registers at the usual
$03D4/$03D5 I/O ports. They're somewhere in the MMIO space. This is
on Windows XP.

Anybody have any info on how to get to them?

Code, drivers, API's?


In the Device Manager the resource information shown for each card would be
structured the same; so, given that $03D4 is at a particular offset within
one of the I/O ranges shown for the first card, you then just add that same
offset to its twin I/O range shown for the secondary card.

It would be a bug in the driver if it was using such resources but not
indicating them in Device Manager - otherwise there is nothing to stop
some other device from trying to use them.

Those registers are basically there for VGA compatibility. There is no
need for a secondary card to use VGA-compatible registers, so those
resources may not be enabled at all.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from
Home Page: http://www.roberthancock.com/