3M M2256PW manual Guidelines for Calibrate Command, Calibrate Procedure

Page 34

34

3M™ Multi-touch Display M2256PW User Guide

Calibrate Procedure

To use the CX command:

1.Enter the Calibrate (CX) command. The controller sends an initial acknowledgment of <SOH>0<CR>.

2.Touch the sensor at a lower left target, which is located 12.5% (1/8) in from the corner of the video image. The controller returns an acknowledgment of <SOH>1<CR>. This is a positive response. If you receive a negative response <SOH>0<CR>, you can cancel the calibration by issuing a Reset command and then start over again.

3.Touch the sensor at an upper right target, which is located 12.5% (1/8) in from the corner of the video image. The controller returns an acknowledgment of <SOH>1<CR>. This is a positive response. If you receive a negative response, you must start over again.

Touching the two valid calibration points results in a successful calibration. If either calibration point is invalid, the calibration fails. The PX controller restores the previous calibration values. If Calibrate fails, repeat the CX process.

Guidelines for Calibrate Command

Here are several guidelines for using the Calibrate commands:

•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.

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:

•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

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.

3M Touch Systems, Inc. Proprietary Information – 37531 Rev D

Page 33 Page 35
Image 34
Page 33 Page 35
Contents 3M Touch Systems, Inc. Proprietary Information 37531 Rev D 3M Multi-touch Display M2256PW User Guide Contents Appendix B 3M PX Serial Controller Communications Appendix a 3M PX USB Controller CommunicationsAppendix C Regulatory Information Overview Important Safety InformationIntroduction Intended UseExplanation of Signal Word Consequences Important Notes Maintaining Your Touch DisplayTouch Sensor Care and Cleaning 3M Touch Systems Support ServicesContact 3M Touch Systems Setting up Your M2256PW Multi-touch Display System RequirementsUnpacking Your Touch Display Cables Included with Your M2256PW Multi-touch DisplayTesting the M2256PW Multi-touch Display Connecting the Touch DisplayArm Mounting Option Video Card Requirements Using the Standard Controls for the Video CardApplicable Display Mode and Refresh Rate Refresh Rate Hz Supported Video Display Modes and Refresh RatesAccess to the Video Controls Configuring the Display SettingsMultimedia Features Menu/Select Down Up Auto/Exit Power LEDAdjusting the M2256PW Video Display Choices DescriptionAudio Tools All Other Platforms Enabling Your M2256PW Multi-touch DisplayWindows 7 USB Compatibility Multitouch Application SupportInstalling 3M MicroTouch Software Video Alignment3M Multi-touch Display M2256PW User Guide Overview of USB Firmware Communications 3M PX USB Controller CommunicationsCommunication Basics Receiving Reports from the Controller Command SetSet Feature Calibration HID Class RequestsDetermining Target Areas Calibration Setup Stage Offset Field Size Value DescriptionCalibration Response Command Status Byte Description Data Stage Offset Field Size Value DescriptionGet Feature GetStatus Valid Command Status Field Entries Response Description Get Feature GetMaxCountPower On Check Bit Fields Bit Number Description Setup Stage Offset Field Size Value DescriptionReset Setup Stage Offset Field Size Value Description Set Feature ResetReset Data Stage Offset Field Size Value Description Asynchronous Reports Set Feature -Restore DefaultsCoordinate Data MultiTouch Digitizer mode Async Report Offset Field Size Value DescriptionTouch Report Structure Offset Field Value DescriptionOverview of Firmware Commands 3M PX Serial Controller CommunicationsCommunicating with the Controller Controller Default SettingsOperating Mode Communication ParametersSending Commands to the Controller Receiving Responses from the ControllerFirmware Commands Controller InitializationMDU Command Code DescriptionCalibrate SOH CxcrGuidelines for Calibrate Command Calibrate ProcedureMode Stream Mode Down UpMode Inactive Get CopyrightSoft Reset Name CommandNull Command Output IdentityUnit Type Restore DefaultsOperating Parameter Default SOH RdcrBit Description Touch Data FormatData Sequence Bits Data Sequence Bits Regulatory Agency Approvals Regulatory InformationFCC-B FCC Warning CE Conformity for Europe
Top Page Image Contents