HP 3336A - Page 65

Appendix A
3-A-4. Handshake.
3-A-5.
Every
character
on
the
Data
Lines
is
asynchronously
transferred
among
various
devices
using
a
three
wire
handshake
technique.
This
technique
coordinates
the
transfer
by
communicating
the
status
of
the
transfer
to
the
active
controller,
talker
and
listener.
The
speed
of
the
transfer
is
determined
by
the
slowest
device
involved
in
the
transfer
and,
therefore,
insures
that
data
is
not
lost.
3-A-6.
Figures
3-A-13
and
3-A-14
are
presentations
of
the
Handshake
sequence.
Hand-
shake
Lines
NRFD
and
NDAC
are
controlled
by
the
listener.
The
Data
Lines
and
Hand-
shake
Line
DAV
are controlled
by
the
talker.