Operation Manual
Single-density graphics
have
a resolution of
60
x
72
dots
per
inch,
and
have a
maximum
width
of 816 dots
per
line.
Double-density,
half-speed
graphics have a resolution
of
120 x
72
dots
per
inch,
and
a
maximum
width
of
1632
dots
per
line. In this
mode,
the
print
head
slows so it can
print
dots that overlap
by
about
1/2
dot
width.
Double-density,
normal-speed
graphics
have
a resolution of 120 x
72
dots
per
inch,
and
a
maximum
width
of 1632
dots
per
line. This
mode
has
the
same
density
as
ESC
Land
prints
at
normal speed.
However,
you
cannot
print
dots
in the
same
row
in
adjacent
columns. In
other
words, after you
have
printed
a
dot
in
one
particular row,
you
cannot
print
on that
row
in the next column.
Quadruple-density
graphics have a resolution
of
240 x
72
dots
per
inch,
and
a
maximum
width
of
3264
dots
per
line. This
mode
prints
dot
columns
that
overlap
by
about
3/4
dot
width.
It
can
print
only
every
other
dot
on
the
same
row. In
other
words,
after
you
have
printed
a
dot
in
one
particular row,
you
cannot
print
on that
row
in
the
next column.
Note
· Let
us
quickly reviev.· the restrictiom.
on
the
ESC
Y
and
ESC 7 graphtcs
modes. Basically, the restrictions just
mean
you cannot
print
a horizontal line
with
fully
overlapping
dots. Even
with
the skips,
dots
on
the
same
row
are close
enough
together that a line
appears
solid. You can, however,
print
dots
in
other
rows. This allows you to create
much
finer curves
and
diagonal lines in these
high
density
modes
.
2.
Number
of
columns
The
Start Graphics code is followed
by
two
numbers
telling
the
printer
how
many
columns
of
graphics to print. For ease
of
reference,
we
call these
numbers
n 1
and
n2.
IBM
Modes
Advanced
Ft·atures
4-9