Datasheet

901
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
Figure 40-4. Touch Screen Pen Detect
The Touch Screen Pen Detect can be used to generate a TSADCC interrupt to wake up the system or it can be
programmed to trig a conversion, so that a position can be measured as soon as a contact is detected if the
TSADCC is programmed for an operating mode involving the Touch Screen.
The Pen Detect generates two types of status, reported in the “TSADCC Status Register”:
• the bit PENCNT is set as soon as a current flows for a time over the debouncing time as defined by PENDBC
and remains set until TSADCC_SR is read.
• the bit NOCNT is set as soon as no current flows for a time over the debouncing time as defined by PENDBC
and remains set until TSADCC_SR is read.
Both bits are automatically cleared as soon as the Status Register TSADCC_SR is read, and can generate an
interrupt by writing accordingly the “TSADCC Interrupt Enable Register”.
X
P
X
M
Y
M
VDDANA
Y
P
VDDANA
GND
GND
To the ADC
GND
Pen Interrupt
Debouncer
PENDBC