Re: PCI BRIDGE transparency???

[Lloyd Bircher <nicad2@yahoo.com>]

Marcial,

> Will the instruction sets of the Pentuin CPU,in
> particular IN  and OUT
> insructions, addressing  the COM port reaches the
> target PCI device at
Actually, IN and OUT are not for only for accessing
the com ports.

> the other side of the bridge as if the bridge is
> transparent? Or are the

Yes, the bridge is transparent with an exception.  The
card and the bridge must have I/O address space
allocated to them.  The card's address space must fall
within the range assigned to the bridge.

> data
> and the address contents released by the Processor
> on the host PCI
> bus the same data and address contents on the local
> PCI bus.?

For the most part, yes.  The PCI bus provides most of
the cycles which are present on the processor bus,
such as memory read/write and I/O read/write.  

> 
> Is there any one who had tried doing what I would
> like to do? Perhaps
> he access maybe the  in C++.

Depending on which compiler and platform you are
developing code for, the I/O ports of you modem can be
accessed quite easily.  DOS and Win9x are the easiest
I've tried.  Many compilers offer "inline" assembly. 
Assembly instructions can be placed in your C or C++
source code.

__________________________________________________
Do You Yahoo!?
Kick off your party with Yahoo! Invites.
http://invites.yahoo.com/