Datasheet

20
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TSC2000
SBAS257
FIGURE 9. X-, Y-, and Z-Coordinate Touch Screen Scan, Initiated by Touch.
Screen
Touch
Issue Interrupt
PENIRQ
Go to Host-Controlled
Conversion
Touch Screen Scan
X, Y, and Z
PENIRQ Initiated
Done
No
No
Yes
Yes
Yes
No
No
Yes
Is Data
Averaging Done
Is Screen
Touched
Is Panel Voltage
Stabilization Done
Turn On Drivers: Y+, Y–
Start Clock
Store Y-Coordinates in
Y-Register
Power Down A/D Converter
Power Up A/D Converter
Reset PENIRQ and
Scan Trigger
Turn Off Clock
Done
Reset PENIRQ and
Scan Trigger
Turn Off Clock
Convert Y-Coordinates
Is PSM = 1
No
Yes
Is Panel Voltage
Stabilization Done
Convert Z
1
-Coordinates
Turn On Drivers: Y+, X–
Power Up A/D Converter
No
Yes
Is Data
Averaging Done
Done
No
Yes
No
Is Screen
Touched
Is Data
Averaging Done
Yes
Convert Z
2
-Coordinates
Store Z
2
-Coordinates
in Z
2
-Register
Reset PENIRQ and
Scan Trigger
Power Down A/D Converter
Turn Off Clock
Issue Data Available
Is Screen
Touched
No
Yes
Yes
Is Panel Voltage
Stabilization Done
Convert X-Coordinates
Turn On Drivers: X+, X–
Power Up A/D Converter
No
Is Data
Averaging Done
Store X-Coordinates
in X-Register
Power Down A/D Converter
Store Z
1
-Coordinates
in Z
1
-Register