Ethernet cable length query - (nf)

[Dave Martindale]

Not all of us have TDR (time-domain reflectometry) equipment at hand to
help find Ethernet cable faults.  The DEC DEUNA Ethernet interfaces,
however, do have a "TDR" register which is supposed to give some sort
of tdr info if all its retries failed.  I expect it is some measure of
the time elapsed between the transceiver starting up and the ocurrence
of the "collision detect" signal.

Now, does anyone know how to interpret this value?  The manuals say
nothing useful, and I haven't been able to make any sense out of the
values I've observed.

	Dave Martindale
	{decvax,allegra,ihnp4,clyde}!watmath!dmmartindale