EXII-7720SC 3M, EXII-7720SC Datasheet - Page 22

• Manufacturer Part Number: EXII-7720SC
• Description: CONTROLLER EX II SER CAPACITIVE
• Manufacturer: 3M
• Series: MicroTouch™ Controller EXr

Specifications of EXII-7720SC

• Accessory Type: Touch Screen - Controller
• Operating Supply Voltage: 5 VDC to 12 VDC
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: - 40 C
• Connector Type: RS232
• Rohs Compliant: Yes
• For Use With/related Products: Touch Screen Capacitive
• For Use With: 3M5754 - TOUCH SCREEN CAPACITIVE 12.31"3M5752 - TOUCH SCREEN CAPACITIVE 19.75"3M5750 - TOUCH SCREEN CAPACITIVE 20.65"3M5748 - TOUCH SCREEN CAPACITIVE 17.54"3M5747 - TOUCH SCREEN CAPACITIVE 6.71"3M5745 - TOUCH SCREEN CAPACITIVE 15.68"3M5744 - TOUCH SCREEN CAPACITIVE 10.83"3M5527 - TOUCH SCREEN CAPACITIVE 31.80"3M5526 - TOUCH SCREEN CAPACITIVE 20.65"3M5525 - TOUCH SCREEN CAPACITIVE 19.75"3M5524 - TOUCH SCREEN CAPACITIVE 17.54"3M5523 - TOUCH SCREEN CAPACITIVE 15.68"3M5522 - TOUCH SCREEN CAPACITIVE 12.31"3M5521 - TOUCH SCREEN CAPACITIVE 10.83"3M5520 - TOUCH SCREEN CAPACITIVE 8.75"3M5519 - TOUCH SCREEN CAPACITIVE 6.71"
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 3M5540

22
Description:
Y = 767 - (768 x 1/8) = 767 - 96 = 671
X = 0 + (1024 x 1/8) = 0 + 128 = 128
Lower Left Calibration Target
Initiates an interactive 2-point calibration.
During the calibration process, you define the active area of the sensor by mapping
locations to an absolute X/Y coordinate system. You touch two target areas on the
sensor. 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 Extended command sets the calibration targets (points) inward from the
corner of the video image. Setting the targets inward makes the calibration process easier
and more accurate.
Guidelines for Calibrate Extended
Here are several guidelines for using the Calibrate Extended 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, suppose the display resolution of your display is 1024 x
768. The Calibrate Extended command calculates the amount to move inward as follows:
•
•
The controller uses the data immediately before liftoff to register a calibration touch.
Therefore, you can touch the sensor, move your finger to the 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 sensor any time the video display changes size or resolution.
You can restart calibration at any time during this sequence by issuing a Reset
command and reissuing a CX command.
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
3M Touch Systems, Inc. Proprietary Information
(0, 767) [0, 1024]*
(0, 0) [0, 0]*
(128, 671)
3M™ MicroTouch™ Controller EX Serial Reference Guide
(895, 96)
(
1023, 0) [1024, 0]*
Upper Right Calibration Target
X = 1023 – (1024 x 1/8) = 1023 – 128 = 895
Y = 0 + (768 x 1/8) = 0 + 96 = 96
[1024, 1024]*