AT32UC3L064-D3HES ATMEL [ATMEL Corporation], AT32UC3L064-D3HES Datasheet - Page 607

• Manufacturer Part Number: AT32UC3L064-D3HES
• Manufacturer: ATMEL [ATMEL Corporation]

26.7.4
32099D–06/2010
Touch Screen Sequencer
Figure 26-3. Touch Screen Pin Connections
The touch screen sequencer is responsible for applying voltage to the resistive touch screen
films as described in
value of the ADP and AD pins. This allows the touch screen sequencer to add a voltage gradient
on one film while keeping the other film floating so a touch can be measured.
The Touch Screen Sequencer will when measuring the vertical position, apply VDD and GND to
the pins connected to X
ment of Y
pad drivers, the actual voltage of X
GND can be used in the contact point calculation to increase accuracy. See second formula in
Section
When the vertical values are converted the same setup is applies for the second axes, by setting
X
details.
P
and X
26.7.2.
M
P
in tristate mode and applying VDD and GND to Y
can proceed without interference. To compensate for ADC offset errors and non ideal
Analog Pin Output Enable (MR.APOE) == 1
Analog Pin Output Enable (MR.APOE) == 0
Section
Y
Y
M
M
P
and X
X
X
M
M
26.7.2. This is done by controlling the output enable and the output
M
. The Y
P
and X
P
and Y
M
is measured as well, so the real values for VDD and
X
X
P
P
M
pins are put in tristate mode so the measure-
Y
Y
P
P
AT32UC3L016/32/64
P
and Y
NC
NC
AD
AD
AD
AD
AD
M
AD
AD
AD
DP
DP
DP
DP
. Refer to
tspo+0
tspo+3
tspo+0
tspo+3
tspo+1
tspo+1
tspo+2
tspo+2
0
1
0
1
Section 26.8.3
607
for