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Re: How to achieve a long burst <OFFTOPIC>?
> Unfortunately, it appears that the bridge chips on PC motherboards do
> not implement DMA engines. Therefore it falls to the peripherals to
> implement DMA.. which also mandates they must be capable of
> becoming the PCI bus master.
Let me take this as a opportunity to answer a question:
What's needed to become a PCI bus master?
We have a processor board that hides behind a
non-transparent Intel 21554 bridge, therefore
seen as a device from the host CPU. The bridge
cannot be arbiter of the primary bus the host
CPU is on but supports the "Master Enable"-Bit
on this side. Would it be sufficient to set this
bit to enable the "Slave-CPU" on the secondary side
of the bridge to do Busmaster-DMA?
Thanks a lot - an sorry to be offtopic.