ATMEGA64A-ANR Atmel, ATMEGA64A-ANR Datasheet - Page 67

• Manufacturer Part Number: ATMEGA64A-ANR
• Description: IC MCU AVR 64K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA64A-ANR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K 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: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.1.3
12.1.4
8160C–AVR–07/09
EIMSK – External Interrupt Mask Register
EIFR – External Interrupt Flag Register
• Bits 7:4 – INT7 - INT0: External Interrupt Request 7 - 0 Enable
When an INT7 - INT4 bit is written to one and the I-bit in the Status Register (SREG) is set (one),
the corresponding external pin interrupt is enabled. The Interrupt Sense Control bits in the Exter-
nal Interrupt Control Registers – EICRA and EICRB defines whether the External Interrupt is
activated on rising or falling edge or level sensed. Activity on any of these pins will trigger an
interrupt request even if the pin is enabled as an output. This provides a way of generating a
software interrupt.
• Bits 7:0 – INTF7 - INTF0: External Interrupt Flags 7 - 0
When an edge or logic change on the INT7:0 pin triggers an interrupt request, INTF7:0 becomes
set (one). If the I-bit in SREG and the corresponding Interrupt Enable bit, INT7:0 in EIMSK, are
set (one), the MCU will jump to the Interrupt Vector. The flag is cleared when the interrupt rou-
tine is executed. Alternatively, the flag can be cleared by writing a logical one to it. These flags
are always cleared when INT7:0 are configured as level interrupt. Note that when entering sleep
mode with the INT3:0 interrupts disabled, the input buffers on these pins will be disabled. This
may cause a logic change in internal signals which will set the INTF3:0 flags. See
Enable and Sleep Modes” on page 72
Bit
0x39 (0x59)
Read/Write
Initial Value
Bit
0x38 (0x58)
Read/Write
Initial Value
INTF7
INT7
R/W
R/W
7
0
7
0
INTF6
INT6
R/W
R/W
6
0
6
0
INTF5
INT5
R/W
R/W
5
0
5
0
for more information.
INTF4
INT4
R/W
R/W
4
0
4
0
INTF3
INT3
R/W
R/W
3
0
3
0
INTF2
INT2
R/W
R/W
2
0
2
0
INTF1
INT1
R/W
R/W
1
0
1
0
ATmega64A
INTF0
INT0
R/W
R/W
0
0
0
0
“Digital Input
EIMSK
EIFR
67