ATMEGA128A-ANR Atmel, ATMEGA128A-ANR Datasheet - Page 91

• Manufacturer Part Number: ATMEGA128A-ANR
• Description: IC MCU AVR 128K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA128A-ANR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP
• Core: AVR8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

13.1.2
8151H–AVR–02/11
EICRB - External Interrupt Control Register B
cleared by writing a logical one to its Interrupt Flag bit (INTFn) in the EIFR Register before the
interrupt is re-enabled.
Table 13-1.
Note:
Table 13-2.
• Bits 7:0 – ISC71, ISC70 - ISC41, ISC40: External Interrupt 7 - 4 Sense Control Bits
The External Interrupts 7 - 4 are activated by the external pins INT7:4 if the SREG I-flag and the
corresponding interrupt mask in the EIMSK is set. The level and edges on the external pins that
activate the interrupts are defined in
before detecting edges. If edge or toggle interrupt is selected, pulses that last longer than one
clock period will generate an interrupt. Shorter pulses are not guaranteed to generate an inter-
rupt. Observe that CPU clock frequency can be lower than the XTAL frequency if the XTAL
divider is enabled. If low level interrupt is selected, the low level must be held until the comple-
tion of the currently executing instruction to generate an interrupt. If enabled, a level triggered
interrupt will generate an interrupt request as long as the pin is held low.
Table 13-3.
Note:
Bit
Read/Write
Initial Value
ISCn1
ISCn1
Symbol
t
0
0
1
1
0
0
1
1
INT
1. n = 3, 2, 1or 0.
1. n = 7, 6, 5 or 4.
ISCn0
When changing the ISCn1/ISCn0 bits, the interrupt must be disabled by clearing its Interrupt
Enable bit in the EIMSK Register. Otherwise an interrupt can occur when the bits are changed.
When changing the ISCn1/ISCn0 bits, the interrupt must be disabled by clearing its Interrupt
Enable bit in the EIMSK Register. Otherwise an interrupt can occur when the bits are changed.
ISCn0
Parameter
Minimum pulse width for asynchronous
external interrupt
0
1
0
1
0
1
0
1
Asynchronous External Interrupt Characteristics
Interrupt Sense Control
Interrupt Sense Control
ISC71
R/W
7
0
Description
The low level of INTn generates an interrupt request.
Any logical change on INTn generates an interrupt request
The falling edge between two samples of INTn generates an interrupt request.
The rising edge between two samples of INTn generates an interrupt request.
Description
The low level of INTn generates an interrupt request.
Reserved
The falling edge of INTn generates asynchronously an interrupt request.
The rising edge of INTn generates asynchronously an interrupt request.
ISC70
R/W
6
0
ISC61
R/W
5
0
(1)
Table
(1)
ISC60
R/W
4
0
13-3. The value on the INT7:4 pins are sampled
ISC51
R/W
Condition
3
0
ISC50
R/W
2
0
Min
ISC41
ATmega128A
R/W
1
0
Typ
50
ISC40
R/W
0
0
Max
EICRB
Units
ns
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