Epson GT-6500 EN - Manual (Page 125)

The offset and scanning lengths (n1 to n4) should be integer values
within the available range of the main scan length and sub scan
length. The maximum main scan and sub scan lengths are determined
by the current resolution and zoom settings, and the parameter range
for the ESC A parameter falls within the values shown below.
0
≤
n1
≤
(maximum main scan length) - 8
0
≤
n2
≤
(maximum sub scan length) - 1
8
≤
n3
≤
(maximum main scan length) - n1
1
≤
n4
≤
(maximum sub scan length) - n2
The sum of the offset length and scanning length, either for the main
scan and sub scan, should not exceed the maximum length determined
by the resolution and zoom settings.
c
Caution:
The length of the m ain scan should alw ays be specified in units
of 8 dots, or an integer m ultiple of 8. O therw ise, a com m and
error occurs in the scanner.
Calculation of the maximum reading area
When the resolution is R dpi and the zoom is H%, the values for the
maximum reading area are obtained with the following calculation.
Main scan : 8
×
INT ((X
L
/Rmax)
×
(R
×
H/100)/8)
Sub scan : INT ((Y
L
/Rmax)
×
(R
×
H/100))
X
L
= The maximum main scan length obtained with
the ESC I command (in dots)
Y
L
= The maximum sub scan length obtained with
the ESC I command (in dots)
Rmax = The maximum resolution setting obtained with
the ESC I command (in dpi)
Note:
INT(X) is a function that returns the integer of the given value X.
Command Reference 3-31