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3M™ MicroTouch™ Controller EX712 Reference Guide
3M Touch Systems, Inc. Proprietary Information
The Calibrate Raw data is a 5-byte packet that includes 1 status byte and 4 bytes of
binary X/Y coordinate data. Each X/Y coordinate includes 10 binary bits and 1 sign bit.
The 10 bits represent coordinates within a range of -1024 to +1023.
To use the Calibrate Raw command, the controller and host system must be in an 8-bit
data communication mode. The Calibrate Raw command returns a negative response if
the controller is not using an 8-bit communication mode. To end Calibrate Raw mode,
issue a Reset command.
3M Touch Systems uses the Calibrate Raw command during manufacturing and testing,
and recommends you only use this command for diagnostics when you want raw data.
Response:
<SOH>
0
<CR> Positive
response.
After the controller is in Calibrate Raw mode, the controller returns a response in the
following format:
SXxYy
where:
S
= Status byte, first byte of data. Refer to Table 5
Xx
= X (horizontal) coordinate data; second and third bytes of data
Yy
= Y (vertical) coordinate data; fourth and fifth bytes of data.
Table 5 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
Table 6 describes the meaning of the bits in the status byte (Byte 1).
Table 6 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.
