M2256PW 3M, M2256PW Datasheet - Page 34

• Manufacturer Part Number: M2256PW
• Description: LCD Touch Panels 22 M2256PW 20 Point Multi-Touch
• Manufacturer: 3M
• Series: -r
• Type: Capacitiver

Specifications of M2256PW

• Length: 18.6" (473.8mm)
• Width: 20.2" (513.2mm)
• Height: 11.6" (296.1mm)
• Interface: USB/Serial
• Diagonal Screen Size: 22" (559mm)
• Lead Free Status / Rohs Status: Details

Y = 1049 - (1050 x 1/8) = 1049 - 131 = 918
34
Guidelines for Calibrate Command
Get Copyright
Syntax:
X = 0 + (1680 x 1/8) = 0 + 210 = 210
Lower Left Calibration Target
Here are several guidelines for using the Calibrate commands:
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•
•
Determining Target Areas
The default calibration targets (points) are located 12.5% (1/8) inward from the corners of
the video image. For example, the resolution of your Windows-based display is 1680 x
1050. The Calibrate Extended command calculates the amount to move inward as
follows:
The Calibrate Extended command then positions the first calibration target inward from
the lower left corner (0,1049) and the second calibration target inward from the upper
right corner (1679,0). The following illustration shows how the calibration targets are
calculated for a Windows-based system. Your operating system may be different.
The illustration below shows the coordinates of the calibration targets and display
corners. The corners show the video coordinates in parentheses and the touch screen
coordinates in brackets. Note that the touch screen coordinates for the serial interface
have their origin in the lower-left corner.
<SOH>Q101<CR>
•
•
The controller uses the data immediately before liftoff to register a calibration touch.
Therefore, you can touch the coordinate target, hold for a few seconds, and then lift
off. Instructing users to touch this way results in a more accurate calibration.
The controller stores the data in non-volatile memory (NOVRAM). Therefore, you
do not have to calibrate the sensor each time you power on the system. You should,
however, recalibrate the touch sensor any time the video display changes size or
resolution.
You can cancel calibration at any time during this sequence by issuing a Reset
command.
Amount to move inward in the X direction: 1680 x 1/8 = 210
Amount to move inward in the Y direction: 1050 x 1/8 = 131
(0, 1049) [0, 0]
(0, 0) [0, 16383]
3M Touch Systems, Inc. Proprietary Information
(210, 918)
(1469, 131)
(
1679, 0) [16383, 16383]
(1679, 1049) [16383, 0]
3M™ Display M2256PW User Guide
Upper Right Calibration Target
X = 1679 – (1680 x 1/8) = 1679 – 210 = 1469
Y = 0 + (1050 x 1/8) = 0 + 131 = 131