Re: accessing device memory
spamtrap@xxxxxxxxxx wrote:
>
>I have recently read on www.hackaday.com "Hiding behind antiquity",
>whislt there is currently no slides or notes from this presentation I
>have wondered for a long time how to access the memory of devices, such
>as the NIC and Graphics Cards.
>
>I have just ordered the " IA-32 Intel® Architecture Software
>Developer's Manual, Volume 1: Basic Architecture" with the hope that
>this will provide me some information as to the address of these
>devices?
That's not nearly enough.
Most of these devices are PCI devices. To get to their memory, you have to
FIND their memory, and that requires knowledge of the PCI configuration
space and how to get to it.
Once you do that, you will have a physical address. You need to convert
that to a virtual address before you can access it.
And once you have done THAT, you still won't know what the memory does. It
might be registers, it might be frame buffer, it might be a buffer list,
who knows. Every device is different.
--
- Tim Roberts, timr@xxxxxxxxx
Providenza & Boekelheide, Inc.
.
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(microsoft.public.windowsce.platbuilder) |
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