Specifications

Chapter 2 Firmware Commands 33
Calibrate New
Note:
MicroTouch provides this command for compatibility with older touchscreen
controllers. To ensure compatibility with all existing and future MicroTouch controllers,
do not use this command when developing your touch drivers and applications.
Syntax: <SOH>CN<CR>
Description: Initiates an interactive, two-point edge calibration.
During the calibration process, you define the active area of the
touchscreen by mapping locations to an absolute X, Y coordinate
system. You touch two target areas on the screen. Touching the
target areas sends the X, Y coordinates for those touch points to the
controller. The controller calculates all other touch points based on
these two points.
The Calibrate New command is similar to the Calibrate Extended
command, except that the calibration points are located at the corners
(edge) of the video image.
Guidelines for Calibrate New
Here are several guidelines for using the Calibrate New command:
The controller uses the data immediately before liftoff to register a
calibration touch. Therefore, users can touch off the target, move
their finger to the target, hold for one second, and then lift off their
finger. 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 screen
each time you power on the system. You should, however,
recalibrate the touchscreen any time the video display changes or
gets repositioned.
You can cancel a calibration at any time by issuing a Reset
command.