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3M™ MicroTouch™ Controller EX Dual Mode Reference Guide
3M Touch Systems, Inc. Proprietary Information – TSD-40848A
Yy
= Y (vertical) coordinate data; fourth and fifth bytes of data.
Table 22. Data Sequence
MSB*
Bits
LSB*
Data Sequence 7
6
5
4
3
2
1
0
S- Byte 1
1
S6
Reserved
X- Byte 2
0
X3
X2
X1
X0
Reserved
x-
Byte
3
0 Xs**
X9 X8 X7 X6 X5 X4
Y- Byte 4
0
Y3
Y2
Y1
Y0
Reserved
y-
Byte
5
0 Ys**
Y9 Y8 Y7 Y6 Y5 Y4
*
MSB = Most Significant Bit, LSB = Least Significant Bit
**
s = sign bit
The following table describes the meaning of the bits in the status byte (Byte 1).
Table 23. Calibrate Raw Status Bits
Bit
Description
Values
S0 – S5 Reserved
—
S6
Proximity (touch state)
1 = Sensor is being touched (a touchdown or a continued touch).
0 = Sensor is not being touched (a touch liftoff or inactive).
When the proximity bit changes from 1 to 0 (touch liftoff), the
controller outputs one final set of X/Y coordinate data with the bit
equal to 0 and the X/Y coordinate data equal to the last touch point.
S7
Packet synchronization
Always 1.
Diagnostic Command
Syntax:
<SOH>
DX
<CR>
Description:
This command requests that the controller check for sensor failures such as broken
corners, broken wires, etc.
Response:
<SOH>
0
<CR> Positive
response.
<SOH>
1
<CR>
Command not supported.
<SOH>
2
<CR> Failure
detected.
Format Raw
Syntax:
<SOH>
FR
<CR>
Description:
Returns the signal level (amount of touch) of each of the four sensor corners in digital
format. The returned values are not corrected for stray values.
The Format Raw data is a 41-byte packet that includes 1 status byte and 40 bytes of
binary corner data. The first byte of each packet always has its high bit (Bit 7) set to
provide synchronization with the host system. Refer to the following table for General
Packet Formats. Each corner data is composed of a pair of 32-bit I and Q values, which
are delivered in 10 bytes.
