Epson EMP-TW 1000, Справочное руководство

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Items not affected by function level
Although higher command levels include all the previous commands
of lower command levels, the parameters for commands used to set
the scanning area (ESC R, ESC H, ESC A) are independent of
function level. These parameters are determined by the physical
characteristics of each scanner; obtain the values available for these
parameters by checking the ID information.
❏
Resolution
The resolutions available vary by scanner model and can be
obtained from the ID information returned by the scanner when
you send the Request ID command. If you use the ESC R
command to specify a resolution that is not available on the
connected scanner, a command error results. The last resolution
listed in the ID information is the maximum resolution available
on the connected scanner.
❏
Maximum scannable area
The maximum scannable area (# of main scan dots
×
# of sub
scan dots) you can set with the ESC A command differs by
scanner model. This value can be calculated from the maximum
resolution and maximum area values found in the ID information.
❏
Zoom setting increments (1% or 10%)
You can adjust the zoom value from 50% to 200%. However, the
minimum increment you can use to adjust the zoom value differs
by scanner model, and is either 1% or 10%. If you make a zoom
setting that is not a multiple of 10% on a scanner that only allows
10% increments, the scanner rounds the setting to the nearest
increment of 10%. (The scanner either corrects or deletes image
data to conform with the ESC A setting. Although this can result
in the image differing slightly from what you expect, you do not
need to take this into consideration within your program.)
❏
Options
To determine whether an option is installed on the connected
scanner, send the ESC F command and check the option flag in
the resulting status byte. You should also use the ESC f command
to determine the maximum scannable area when the option is
installed.
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Command Usage