User guide

20 3M™ MicroTouch™ Controller SX112 Reference Guide
3M Touch Systems, Inc. Proprietary Information
Calibrate Raw
Syntax: <SOH>CR<CR>
Description: Allows the collection of raw (signed) X and Y coordinates before the normal scaling,
linearization, and filtering processes. The controller sends a continuous stream of data in
Calibrate Raw mode.
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 Error! Reference source
not found.6.
Xx = X (horizontal) coordinate data; second and third bytes of data
Yy = Y (vertical) coordinate data; fourth and fifth bytes of data.
Table 6 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 7 describes the meaning of the bits in the status byte (Byte 1).