Datasheet

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t
COORDINATE
+
OH2
f
OSC
)3 @
ǒ
t
PVS
)t
PRE
)t
SNS
)
OH
DLY1
f
OSC
Ǔ
)4 @
ǒ
N @
ǒ(
B)2
)
@
f
OSC
f
ADC
)OH
CONV
Ǔ
@
ǒ
1
f
OSC
Ǔ
)
ǒ
L
PPRO
f
OSC
Ǔ
Ǔ
(6)
Programmedfor
Self-Control
(PSM=1)
X-Y-Z -Z ScanMode
(ControlByte1
D[6:3]=0000)
1 2
TSC
NotAddressed
Sample,Conversion,
andPreprocessingfor
YCoordinate
Sample,Conversion,
andPreprocessingfor
XCoordinate
Sample,Conversion,
andPreprocessingfor
Z CoordinateandZ Coordinate
1 2
Sample,Conversion,
andPreprocessingfor
YCoordinate
Reading
X-Data
Register
TouchisDetected
Detecting
Touch
Detecting
Touch
Detecting
Touch
Detecting
Touch
Reading
Y-Data
Register
Reading
Z -Data
Register
1
Reading
Z -Data
Register
2
TouchisDetected TouchisDetected
TouchisDetected
PINTDAV Programmed:
As ,
CFR2,D[15:14]=10
PENIRQ
As ,
CFR2,D[15:14]=11or01
DAV
As and ,
CFR2,D[15:14]=00
PENIRQ DAV
t
COORDINATE
Detecting
Touch
TSC2004
SBAS408E – JUNE 2007 – REVISED MARCH 2008
If the pressure of the touch is also to be measured, the process continues in the same way, but measuring the Z
1
and Z
2
values instead, and storing the results in temporary registers. Once the complete sample set of data (X,
Y, Z
1
, and Z
2
) are available, they are loaded in the X, Y, Z
1
, and Z
2
registers. This process is illustrated in
Figure 40 . As before, this process time depends upon the settings described above. The time for a complete X,
Y, Z
1
, and Z
2
coordinate reading is given by:
Where:
OH2 = overhead time #2 = 3.5 internal clock cycles.
Figure 40. Example of an X, Y, and Z Coordinate Touch Screen Scan using TSMode 1
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