AT91SAM9R64-CU-999 Atmel, AT91SAM9R64-CU-999 Datasheet - Page 830

• Manufacturer Part Number: AT91SAM9R64-CU-999
• Description: IC MCU ARM9 64K SRAM 144LFBGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM9R64-CU-999

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 240MHz
• Connectivity: EBI/EMI, I²C, MMC, SPI, SSC, UART/USART, USB
• Peripherals: AC'97, POR, PWM, WDT
• Number Of I /o: 49
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: ROM
• Ram Size: 72K x 8
• Voltage - Supply (vcc/vdd): 1.08 V ~ 1.32 V
• Data Converters: A/D 3x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 144-LFBGA
• Processor Series: AT91SAMx
• Core: ARM926EJ-S
• Data Bus Width: 32 bit
• Data Ram Size: 64 KB
• Interface Type: SPI, TWI, UART
• Maximum Clock Frequency: 240 MHz
• Number Of Programmable I/os: 118
• Operating Supply Voltage: 1.65 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: JTRACE-ARM-2M, MDK-ARM, RL-ARM, ULINK2
• Development Tools By Supplier: AT91SAM-ICE, AT91-ISP, AT91SAM9RL-EK
• Minimum Operating Temperature: - 40 C
• For Use With: AT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

Figure 43-2. Touch Screen Position Measurement
43.6.2
830
AT91SAM9R64/RL64 Preliminary
Position Measurement Method
As shown in
bottom. Due to the linear resistance of the film, there is a voltage gradient from top to bottom.
When a contact is performed on the screen, the voltage propagates at the point the two surfaces
come into contact with the second film. If the input impedance on the right and left electrodes
sense is high enough, the film does not affect this voltage, despite its resistive nature.
For the horizontal direction, the same method is used, but by applying supply from left to right.
The range depends on the supply voltage and on the loss in the switches that connect to the top
and bottom electrodes.
In an ideal world (linear, with no loss through switches), the horizontal position is equal to:
The proposed implementation with on-chip power switches is shown in
measurement at the output of the switch compensates for the switches loss.
It is possible to correct for the switch loss by performing the operation:
This requires additional measurements, as shown in
Vertical Position Detection
X
X
M
P
VY
[VY
M
P
Y
/ VDD or VY
- VX
M
Figure
Y
P
M
] / [VX
Volt
VDD
43-2, to detect the position of a contact, a supply is first applied from top to
GND
P
P
X
M
/ VDD.
- VX
Contact
Pen
M
] .
X
P
Horizontal Position Detection
Y
Y
M
P
Y
P
Figure
X
P
43-3.
Volt
VDD
GND
Figure
6289C–ATARM–28-May-09
43-3. The voltage