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3M™ MicroTouch™ Controller EX Serial Reference Guide
3M Touch Systems, Inc. Proprietary Information -- 29087v03
I and Q are complex touch currents as measured in phase and 90 degrees out of phase
with the corner drive signal. Refer to Table 9 for I/Q Corner Components.
To use the Format Raw command, the controller and host system must be in an 8-bit data
communication mode. The Format Raw command returns a negative response if the
controller is not using an 8-bit communication mode.
To terminate Format Raw, issue a Reset command. The controller may return several
bytes of data between the time you issue a Reset command and the controller receives it.
You can either scan the data stream for the Reset acknowledgment, or you can ignore the
response to the first Reset command and then issue a second Reset after approximately 10
seconds has passed.
Use the Format Raw command for diagnostics. Use Format Tablet for standard sensor
operation.
Response:
<SOH>
0
<CR> Positive
response.
After the controller is in Format Raw mode, the controller returns a continuous response
in the following format:
<
41-byte-packet
><
41-byte-packet
>...<
41-byte-packet
>...
Table 8 General Packet Formats
Byte
Bits 0 – 7
1
b0 – b6: Reserved
b7: Synchronization bit (Always 1)
2-6
I component of upper left (UL) corner
7-11
Q component of upper left (UL) corner
12-16 I component of upper right (UR) corner
17-21 Q component of upper right (UR) corner
22-26 I component of lower left (LL) corner
27-31 Q component of lower left (LL) corner
32-36 I component of lower right (LR) corner
37-41 Q component of lower right (LR) corner
Table 9 I/Q Corner Components
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