C2254PW 3M, C2254PW Datasheet - Page 35

• Manufacturer Part Number: C2254PW
• Description: LCD Touch Panels 22 C2254PW 10 Point Multi-Touch
• Manufacturer: 3M
• Series: -r
• Type: Capacitiver

Specifications of C2254PW

• Length: 18.6" (473.8mm)
• Width: 19.7" (500mm)
• Height: 11.6" (296.1mm)
• Interface: USB/Serial
• Diagonal Screen Size: 22" (559mm)
• Lead Free Status / Rohs Status: Details

3M™ Multi-Touch Chassis Display User Guide
Note 1: P is the proximity bit. It is set to 1 when there is a touch, 0 for a liftoff.
Data Format
Data format refers to the type of packet the controller uses to send the X/Y touch
coordinates to the host system. Format Tablet Multitouch is the default format for the
3M™ PX serial controller. In Format Tablet Multitouch, the controller sends 6 bytes per
point and provides the most rapid response time to a touch.
Note that 3M MicroTouch Software automatically sets communications parameters to
N81.
The format is a six byte packet that includes one status byte, four bytes of binary X,Y
position data and a touch ID. The X,Y coordinates are 14 bits, providing a range of 0 to
16,383. The data is sent in the following format:
Table 17. Touch Data Format Settings
The ID is associated with a touch stream from one finger. The ID, in the range of 0-127,
is assigned on a rotating basis at touchdown. A finger touch stream consists of a
touchdown, maybe some continuing touch points, ending with a liftoff. The ID is
released on liftoff, and becomes available to be reassigned.
When multiple fingers are down, the packets from the touch streams are sent interleaved.
There is no order imposed on the interleave.
Operating Mode
The operating mode specifies the conditions under which the controller sends the X/Y
touch coordinates (input data packet) to the host system.
Mode Stream is the default operating mode for the 3M™ PX serial controller. In Mode
Stream, the controller sends a continuous stream of data packets when the sensor is
touched. The controller sends the data as long as a touch continues on the sensor.
Because Mode Stream sends touch data continually, it is the most versatile mode, and it
provides the best response time and overall feel.
Data Sequence
Status - Byte 1
X - Byte 2
X - Byte 3
Y - Byte 4
Y - Byte 5
ID – Byte 6
3M Touch Systems, Inc. Proprietary Information -- 37732v04
Bits
7
1
0
0
0
0
0
6
P
X6
X13
Y6
Y13
N6
1
5
0
X5
X12
Y5
Y12
N5
4
0
X4
X11
Y4
Y11
N4
3
0
X3
X10
Y3
Y10
N3
2
0
X2
X9
Y2
Y9
N2
1
0
X1
X8
Y1
Y8
N1
0
0
X0
X7
Y0
Y7
N0
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