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RE: Axcessing *R_PAR1_CTRL_DATA from programs under Linux.

On 2001.04.30 12:13:05 Jonas Aaberg wrote:
> On 2001.04.30 12:24:47 Mikael Starvik wrote:
> > The internal registers are not available from userspace
> > (I don't think you can find any platform with a MMU
> > that lets you tamper with hardware registers directly).
> > If you need to access the registers you should do it
> > from kernel space e.g. from a device driver.
> I thought so too, but I found it quite nice to be able to
> do that in userspace on the old Etrax, so I hoped there
> was a way to do that. 
> Thanks for your answer.

But on a second thought, for example the X server must be
able to change internal registers to switch to graphic mode.
So I think it can be possible from a program running with
chmod +s, owner root to change internal registers, somehow.
Could it be possible to memory map the interal register area
as shared memory? Just an idea, mabye it is impossible.


Jonas Aaberg               Email: aberg@xxxxxxx.ch
Supercomputing Systems AG  Web:   http://www.scs.ch
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