Can IDE cable's end connector be left idle ( w-o affecting data transfer ) ?
In comp.sys.ibm.pc.hardware.storage Jeff Richards wrote:
But that's the point. While the device might incorporate a terminator, that
doesn't make it a terminated device. If the terminator is enabled then it
becomes a device plus a terminator - exactly the same as a device with a
pass-through connection and a terminator plugged into the end of the chain.
Unfortunattely that is not true.
It's a fine distinction, but unless you make it clear then you will make the
mistakes apparent in your comments, confusing what a device does in terms of
line impedance etc with what a terminator does. They are different things
and they have different effects.
A device-integrated terminator is at the end of the "T". A
cable attached or integrated terminator is at the end of the bus.
The two things coincide if the cable end-connector is attached
to the terminated device. Otherwise they do not.
And, yes, a device-integrated terminator turns a device into a
terminated device. A cable attached or cable integrated terminator
creates a terminated cable. It is a difference and it may be important
for fast buses. It is critical if there are terminated devices in the
middle of the bus, like ATA UDMA termination does.
Arno
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