Backspace (08) <bs, Horizontal tab (09) <ht, Line feed (0a) <lf – IBM 32x User Manual
Page 37: Backspace, Horizontal, Line, Feed
carriage
return,
or
display
position
command
is
written
to
the
top
line.
The
test
and
reset
commands
stop
the
scrolling
message
regardless
of
the
display
position.
Backspace
(08)
<BS>
08
Purpose:
Decrements
the
cursor
position
by
one
and
clears
any
character
displayed
in
that
position.
If
the
write
position
is
at
the
lower
left,
the
position
is
moved
to
the
upper
right,
and
if
it
is
at
the
upper
left,
it
is
moved
to
the
lower
right.
This
commands
stops
the
scrolling
alphanumeric
message
if
the
cursor
position
is
on
the
top
line
when
this
command
is
sent.
Horizontal
tab
(09)
<HT>
09
Purpose:
Increments
the
cursor
position
by
one.
No
characters
are
erased.
This
command
stops
the
scrolling
message
if
the
cursor
position
is
on
the
top
line
when
the
command
is
sent.
At
the
end
of
a
line,
the
display
behavior
is
determined
by
the
state
of
the
display
control
mode
as
follows:
Normal
Display
Control
Mode
(DC1)
If
the
cursor
is
at
the
upper
right
position,
it
is
moved
to
the
lower
left
position.
If
the
cursor
is
at
the
lower
right
position,
it
is
moved
to
the
upper
left
position.
Vertical
Scroll
Display
Control
Mode
(DC2)
If
the
cursor
is
at
the
upper
right
position,
it
is
moved
to
the
lower
left
position.
If
the
cursor
is
at
the
lower
right
position,
the
characters
displayed
on
the
bottom
line
are
moved
to
the
top
line,
the
bottom
line
is
cleared,
and
the
cursor
is
moved
to
the
lower
left
position.
Line
feed
(0A)
<LF>
0A
Purpose:
The
display
behavior
is
determined
by
the
state
of
the
display
control
mode
as
follows:
Normal
Display
Control
Mode
(DC1)
The
cursor
is
moved
to
the
same
position
in
the
complementary
line.
In
this
mode,
a
line-feed
command
stops
the
scrolling
alphanumeric
message
if
the
cursor
is
on
the
top
line
when
this
command
is
sent.
Vertical
Scroll
Display
Control
Mode
(DC2)
If
the
cursor
is
on
the
top
line,
it
is
moved
to
the
complementary
position
on
the
bottom
line.
If
the
cursor
position
is
on
the
bottom
line,
all
characters
on
that
line
are
moved
to
the
top
line,
the
bottom
Input/output
device
commands
11-9-2005
Appendix
A.
Input/output
device
commands
A-5