EXII-7720SC 3M TOUCH SYSTEMS, EXII-7720SC Datasheet - Page 25

• Manufacturer Part Number: EXII-7720SC
• Manufacturer: 3M TOUCH SYSTEMS

Specifications of EXII-7720SC

• Operating Temperature (min): -40C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Rad Hardened: No
• Lead Free Status / Rohs Status: Compliant

EX II Controller Communications
Format Raw
Syntax:
Description:
Response:
<SOH>FR<CR>
Returns the signal level (amount of touch) of each of the four touch screen 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 Table 6 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.
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 7 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 touch
screen operation.
<SOH>0<CR>
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 6 General Packet Format
Byte
1
2-6
7-11
12-16
17-21
22-26
27-31
32-36
37-41
Bits 0 – 7
b0 – b6: Reserved
b7: Synchronization bit (Always 1)
I component of upper left (UL) corner
Q component of upper left (UL) corner
I component of upper right (UR) corner
Q component of upper right (UR) corner
I component of lower left (LL) corner
Q component of lower left (LL) corner
I component of lower right (LR) corner
Q component of lower right (LR) corner
3M Touch Systems Proprietary Information
Positive response.
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