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Date: Thu, 16 Oct 2008 15:48:50 -0700
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Subject: Re: [Doubt] Can a PCI device communicate with another PCI or other
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In <e6a0706a0810161130i6a3820fexf3afdbf28f81bd31@mail.gmail.com> mboxindia@gmail.com wrote:
>I think a PCI device can communicate with another PCI device directly
>without the intervention of the CPU.

Absolutely.  Happens a fair amount in embedded networking systems (among
others).

The host is responsible for enumeration and resource assignment, but once
that's complete, any device on the bus can see all others.  Whether that's
useful depends rather heavily on the devices on the bus, obviously.

TANSTAAFL applies, though, in that multiple initiators must be careful not
to step on each others' accesses.

-- 
Steve Watt KD6GGD  PP-ASEL-IA          ICBM: 121W 56' 57.5" / 37N 20' 15.3"
 Internet: steve @ Watt.COM                      Whois: SW32-ARIN
   Free time?  There's no such thing.  It just comes in varying prices...