Here's my 0.02

Michael Graff wrote:
> 
> 
> It seems like the chain is more or less
> 
> hardware_bus <--> wdc <--> wd
>                    ^
>                    +-----> atapi <--> CDROM (etc)
> 
In my PC experience the whole IDE/ATA thing a bit of an exercise in trying
to make things cheaper...

The bus interface is nothing but a bus extender with all the intelegence
on the devices. Since you can't program the bus interface and the
controller is integrated with the device the division between controller
and device is 'very' grey.

Since the ATA H/W spec defines a master and slave device, would it not be
better to tie the controller (wdc) to the master device and have a slave
hanging off the master? Very messy in my view, but that's what the
hardware does.

Else, a pseudo controller with devices hanging off it...? Problem then what
if the 'master' device is less intelegent than the slave, ie. a old ATA
DISK and a new ATAPI CDROM or tape that can do DMA etc?

I guess you can always put it on the second bus extender, or do what PC
owners do - upgrade... :-)

et
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Ernst J. du Toit (TED5)           Internet: ernstjdt@maxwell.ctech.ac.za
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