3M SC400 Serial Resistive, Справочное руководство

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20 SC400 Controller Reference Guide
3M Touch Systems Proprietary Information
Determining Target Areas
The default calibration targets (points) are located 12.5% (1/8) inward from the corners of
the video image. For example, suppose the display resolution of your monitor is 1024 x
768. The C3 calculates the amount to move inward as follows:
•
Amount to move inward in the X direction: 1024 x 1/8 = 128
•
Amount to move inward in the Y direction: 768 x 1/8 = 96
The C3 command then positions the first calibration target inward from the lower left
corner and the second calibration target inward from the upper right corner. Figure 2
shows how the calibration targets are calculated.
Figure 2 Calibration Target Locations
Enter Sleep
Syntax: <SOH> ES <CR>
Response: <SOH> 0 <CR> Positive response.
Description: This command is a power management feature that lets you put the controller into a low
power mode (4-5 mA) when not in use. Send this command to put the controller in a low
power state. The controller returns to a normal power level on touch. If you need to send
a command to the controller when it is in a low power state, first raise CTS.
Upper Right Calibration Target
X = 1023 – (1024 x 1/8) = 1023 – 128 = 895
Y = 0 + (768 x 1/8) = 0 + 96 = 96
Lower Left Calibration Target
X = 0 + (1024 x 1/8) = 0 + 128 = 128
Y = 767 - (768 x 1/8) = 767 - 96 = 671
(0, 0) [0, 1024]*
(0, 767) [0, 0]*
(
1023, 0) [1024, 1024]*
(128, 671)
(895, 96)
[1024, 0]*
* The coordinates are in video terms, with the origin (0, 0) in the upper left corner of the screen. Examples
from the controller’s perspective however, place the origin at the lower left corner of the screen (numbers
in brackets). The controller outputs 0 to 1024 for both axes, regardless of display resolution.
(128, 96)
Upper Left Calibration Target
X = 1024 x 1/8 = 128
Y = 768 x 1/8) = 96