ATMEGA1281-16AU Atmel, ATMEGA1281-16AU Datasheet - Page 71

• Manufacturer Part Number: ATMEGA1281-16AU
• Description: IC MCU AVR 128K FLASH 64-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA1281-16AU

• 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: 54
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 8K 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, 64-VQFP
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Interface Type: 2-Wire/SPI/USART
• Total Internal Ram Size: 8KB
• # I/os (max): 54
• Number Of Timers - General Purpose: 6
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 64
• Package Type: TQFP
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 8 KB
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 6
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRRZ541, ATAVRRAVEN, ATAVRRZRAVEN, ATAVRRZUSBSTICK, ATAVRISP2, ATAVRRZ201
• Minimum Operating Temperature: - 40 C
• Controller Family/series: AVR MEGA
• No. Of I/o's: 54
• Eeprom Memory Size: 4KB
• Ram Memory Size: 8KB
• Cpu Speed: 16MHz
• Rohs Compliant: Yes
• For Use With: ATSTK600-TQFP64 - STK600 SOCKET/ADAPTER 64-TQFPATAVRDB101 - MODULE DISPLAY LCD/RGB BACKLIGHT770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

12.2
12.2.1
2549M–AVR–09/10
Ports as General Digital I/O
Configuring the Pin
Note that enabling the alternate function of some of the port pins does not affect the use of the
other pins in the port as general digital I/O.
The ports are bi-directional I/O ports with optional internal pull-ups.
tional description of one I/O-port pin, here generically called Pxn.
Figure 12-2. General Digital I/O
Note:
Each port pin consists of three register bits: DDxn, PORTxn, and PINxn. As shown in
34 and Table 12-35 relates the alternate functions of Port L to the overriding signals shown in
Figure 12-5 on page 76.” on page
PORTxn bits at the PORTx I/O address, and the PINxn bits at the PINx I/O address.
The DDxn bit in the DDRx Register selects the direction of this pin. If DDxn is written logic one,
Pxn is configured as an output pin. If DDxn is written logic zero, Pxn is configured as an input
pin.
If PORTxn is written logic one when the pin is configured as an input pin, the pull-up resistor is
activated. To switch the pull-up resistor off, PORTxn has to be written logic zero or the pin has to
be configured as an output pin. The port pins are tri-stated when reset condition becomes active,
even if no clocks are running.
Pxn
1. WRx, WPx, WDx, RRx, RPx, and RDx are common to all pins within the same port. clk
SLEEP, and PUD are common to all ports.
PUD:
SLEEP:
clk
I/O
:
PULLUP DISABLE
SLEEP CONTROL
I/O CLOCK
ATmega640/1280/1281/2560/2561
SLEEP
(1)
99, the DDxn bits are accessed at the DDRx I/O address, the
SYNCHRONIZER
D
L
Q
Q
D
PINxn
Q
Q
RESET
RESET
PORTxn
WDx:
RDx:
WRx:
RRx:
RPx:
WPx:
Q
Q
Q
Q
DDxn
CLR
CLR
D
D
RRx
WRITE DDRx
READ DDRx
WRITE PORTx
READ PORTx REGISTER
READ PORTx PIN
WRITE PINx REGISTER
PUD
WDx
RDx
RPx
clk
1
0
Figure 12-2
I/O
WRx
WPx
shows a func-
“Table 12-
71
I/O
,