Block
Data
Transfer
The cursor
might
be repositioned
either
backward or forward.
For
forward repositioning,
the
start
point
is
usually
the
start
of
the
next
unprotected
or
transmit-only
field. When
it
is
repositioned backward, a
search
is made for one of
the
following: column I
of
the
current
line,
the
first
block
terminator
or non-displaying terminator,
the
home up position,
the
logical
start-of-text, or
the
((Start
Col"
position selected on
the
Terminal Configuration menu.
Then
the
cursor is located
at
this
point, which becomes
the
start
point.
When
the
AutoTerm(J)
field is
set
to ((Yes", the cursor is repositioned before
handshaking
is
done (if
handshaking
is
selected);
in
fact, before even
the
first
DCI
is received from
the
host.
For
all
other
menu
field selections affecting cursor repositioning,
the
cursor is positioned
after
handshaking
is completed.
Cursor positioning
after
an
• keystroke is different from
that
of
the
send
display (Ec
d)
escape sequence
in
that
when
the
((Ec
d"
escape sequence
is
used,
the
cursor
is
never
repositioned.
END
POINT
SELECTION.
The
endpointis determinedby one
or
more((terminatingagents",
as
listed below:
• Block
terminator
(BT).
• Non-displaying
terminator
(NDT).
•
End
of
the
line.
•
End
of
the
field (unprotected or transmit-only).
•
End
of
the
workspace.
In
many
cases,
the
data
block canbe
terminated
by more
than
one agent.
In
such
cases,
the
first
agent
encountered ends
the
block.
DATA
TRANSFER.
The
type
of
data
transferred
depends on
the
current
combination
of
terminal
modes.
Data
types
that
might
be
transferred
are
as
follows:
• ASCII displayable characters.
• ASCII control codes (characters).
• Video
enhancement
escape sequences.
•
Alternate
character
set
escape sequences.
• Field definition escape sequences.
•
Edit
check escape sequences.
Field definition
types
include: unprotected fields, protected fields,
transmit-only
fields,
and
security
fields.
Edit
check types include: numeric-only, alphabetic-only,
and
all
characters.
END
CHARACTER
TRANSFER.
When
the
last
character
of
the
data
block
has
been sent,
the
terminal
adds one
or
more
((end
characters" to
the
data
block. These
are
as
follows:
• Block terminator.
•
Carriage
return.
• Line feed (if enabled).
The
type
of
end
character(s)
transmitted
depends on
the
terminal
mode combination.
9-8
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