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EX II Serial Controllers Reference Guide
3M Touch Systems Proprietary Information
Table 7 I/Q Corner Component
Byte
Bits 0 – 7
N
b0 – b6: bits 25-31 of respective I/Q corner data
b7: Always 0
N+1
b0 – b6: bits 18-24 of respective I/Q corner data
b7: Always 0
N+2
b0 – b6: bits 11-17 of respective I/Q corner data
b7: Always 0
N+3
b0 – b6: bits 4-10 of respective I/Q corner data
b7: Always 0
N+4
b0 – b3: bits 0-3 of respective I/Q corner data
b4 – b7: Always 0
Format Tablet
Syntax: <SOH>
FT
<CR>
Description: Outputs the X/Y touch coordinate data in a 5-byte packet. The packet includes 1 status
byte and 4 bytes of binary X/Y coordinate data. The protocol also establishes the X and Y
coordinate output as 14 binary bits providing a range of 0 to 16,383.
The low order bits (X3 – X0 and Y3 – Y0) are not significant in a 1024 by 1024 touch
screen because data can fluctuate with each touch, and therefore may not be completely
accurate.
To use Format Tablet, the controller and host system must be in an 8-bit data
communication mode. The Format Tablet command returns a negative response if the
controller is in 7-bit format.
Response:
<SOH>
0
<CR> Positive
response.
With the controller in Format Tablet mode, touching the screen causes the controller to
return a response in the following format:
SXxYy
S
= Status byte, first byte of data. Refer to Table 8.
Xx
= X (horizontal) coordinate data; second and third bytes of data.
Yy
= Y (vertical) coordinate data; fourth and fifth bytes of data.
