AT91SAM7A1-AU Atmel, AT91SAM7A1-AU Datasheet - Page 320

• Manufacturer Part Number: AT91SAM7A1-AU
• Description: IC ARM7 MCU 32BIT ROMLESS144LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7A1-AU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 40MHz
• Connectivity: CAN, EBI/EMI, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 49
• Program Memory Type: ROMless
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 144-LQFP
• For Use With: AT91SAM7A1-EK - BOARD EVAL FOR AT91SAM7A1
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

26.6
320
External Edge Detection
AT91SAM7A1
CLK must therefore be at least CORECLK/1024 (29.3 kHz) in order to obtain an equal condi-
tion after 0.1 seconds.
Rounding value to 2929 (0x0B71) generates a 0.01% error.
The timer contains many external edge detection options.
The operating mode determines their number:
For each edge detection, it is possible to choose a rising edge, a falling edge or both.
Whereas when a reset is caused, it occurs at the next valid counter clock edge.
If an external trigger is used, each of its pulses must have a duration strictly greater than the
CORECLK period.
2. Calculate the register value with this clock using the following equation:
• Capture mode
• Waveform mode: Dual waveform mode
• Waveform mode: Single waveform mode
Compare Value
– TIOAx as load register and external trigger
– TIOBx as external trigger
– XC0, XC1 or XC2 as external trigger
– TIOBx as external trigger
=
0.1
CORECLK
---------------------------- -
DIV
–
1
=
0.1
30 000 000
----------------------------------- -
1024
–
1
6048B–ATARM–29-Jun-06
=
2928.69