SAM9RL64 Atmel Corporation, SAM9RL64 Datasheet - Page 831

• Manufacturer Part Number: SAM9RL64
• Manufacturer: Atmel Corporation

Specifications of SAM9RL64

• Flash (kbytes): 0 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 240 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 118
• Ext Interrupts: 118
• Usb Transceiver: 1
• Usb Speed: Hi-Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 2
• Uart: 5
• Ssc: 2
• Sd / Emmc: 1
• Graphic Lcd: Yes
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 6
• Adc Resolution (bits): 10
• Adc Speed (ksps): 220
• Resistive Touch Screen: Yes
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 64
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.08 to 1.32
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Figure 43-3. Touch Screen Switches Implementation
43.6.3
6289D–ATARM–3-Oct-11
Pen Detect Method
When there is no contact, it is not necessary to perform conversion. However, it is important to
detect a contact by keeping the power consumption as low as possible.
The proposed implementation polarizes the vertical panel by closing the switch on X
the horizontal panel by an embedded resistor connected to Y
switch. Since there is no contact, no current is flowing and there is no related power consump-
tion. As soon as a contact occurs, a current is flowing in the touch screen and a schmitt trigger
detects the voltage in the resistor.
The Touch Screen Interrupt configuration is entered by programming the bit PENDET in the
“TSADCC Mode
tor are both closed, except when a touch screen conversion is in progress.
To complete the circuit, a programmable debouncer is placed at the output of the schmitt trigger.
This debouncer is programmable at 1 ADC Clock period, useful when the system is running at
Slow Clock, or at up to 2
Horizontal Position Detection
X
X
VDDANA
M
P
GND
X
Y
X
Y
M
M
P
P
Resistor
Switch
Resistor
Register”. If this bit is written at 1, the switch on X
Switch
Y
15
P
ADC Clock periods, but better used to filter noise on the Touch
VDDANA
VDDANA
GND
GND
Vertical Position Detection
Y
Y
VDDANA
M
P
GND
To the ADC
Resistor
Switch
Resistor
Switch
AT91SAM9R64/RL64
M
. This resistor is enabled by a fifth
X
P
P
and the switch on the resis-
P
and ties
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