Command
Received?
Operating mode
= 1, 2, or 3?
Process
Command
Get Hall Angle and
Magnetude
Update Circle LEDs
Hall mag above
threshold?
Get LDC3114
Button States
Update Button LEDs
Change in Button
Status?
Haptic FB
Get Hall Angle and
Magnetude
Update Circle LEDs
Hall mag above
threshold?
Op Mode = 3
Get LDC3114
Data Values
Determine largest
value
Update LEDs based
on max force
Op Mode = 2
Operating
Mode > 3?
Reset Op Mode to 1
Get Hall Angle and
Magnetude
Update Circle LEDs
Hall mag above
threshold?
Op Mode = 1
Change in Button
Status?
Haptic FB
Collect Data
for GUI
Yes
1
2
3
No
No
Yes
No
No
Yes
Yes
No
Yes
Yes
No
No
Yes
No
Figure 3-2. Operational Modes Flowchart
During normal operation, this reference design has three different operational modes that change the functions
of the inductive touch buttons.
Hardware, Software, Testing Requirements, and Test Results
Inductive Touch and Magnetic Dial Contactless User Interface Reference
Design
11
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