12 Apr
2005
12 Apr
'05
9:23 p.m.
On 4/12/05, Vintage Computer Festival <vcf at siconic.com> wrote:
On Tue, 12 Apr 2005, Ethan Dicks wrote:
The HP cable itself is quite ordinary... pin 1 to pin 1... pin 25 to
pin 25, with each pin going to the pod as well as between the two
devices. The magic in this case is going to be in the pod, not the
cable. One can certainly build an integral pod/cable, but that's not
what HP did. They kept the cable itself as simple as possible.
I don't know for sure what's in the pods, but now that we are
disussing it, I do seem to recall that I heard relays clicking when
entering and exiting monitoring modes. There is plenty of room for
passive and not-so-passive components in there as well.
-ethan
The physical cable used with HP line analysers is
a simple Y-split -
25-position ribbon cable...
I have limited experience with this as I only tried it once, but when I
did I noticed that either one or the other computer was greedy and took
all the bits for itself, and the other computer didn't get any signal, so
I always assumed you needed some sort of "special" cable in order to split
an RS-232 signal.