ATmega1281 Atmel Corporation, ATmega1281 Datasheet - Page 350

• Manufacturer Part Number: ATmega1281
• Manufacturer: Atmel Corporation

Specifications of ATmega1281

• Flash (kbytes): 128 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 17
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 8
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 6
• Output Compare Channels: 16
• Input Capture Channels: 2
• Pwm Channels: 8
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

30.8.1
30.8.2
2549N–AVR–05/11
Serial Programming Pin Mapping
Serial Programming Algorithm
Table 30-15. Pin Mapping Serial Programming
Figure 30-10. Serial Programming and Verify
Notes:
Depending on CKSEL Fuses, a valid clock must be present. The minimum low and high periods
for the serial clock (SCK) input are defined as follows:
Low: > 2 CPU clock cycles for f
High: > 2 CPU clock cycles for f
When writing serial data to the ATmega640/1280/1281/2560/2561, data is clocked on the rising
edge of SCK.
When reading data from the ATmega640/1280/1281/2560/2561, data is clocked on the falling
edge of SCK. See
Symbol
1. If the device is clocked by the internal Oscillator, it is no need to connect a clock source to the
2. V
PDO
SCK
PDI
XTAL1 pin.
programming the EEPROM, an auto-erase cycle is built into the self-timed programming oper-
ation (in the Serial mode ONLY) and there is no need to first execute the Chip Erase
instruction. The Chip Erase operation turns the content of every memory location in both the
Program and EEPROM arrays into 0xFF.
CC
- 0.3V < AVCC < V
Figure 30-12 on page 353
(TQFP-100)
Pins
PB2
PB3
PB1
PDO
SCK
PDI
ck
ck
CC
ATmega640/1280/1281/2560/2561
< 12MHz, 3 CPU clock cycles for f
< 12MHz, 3 CPU clock cycles for f
+ 0.3V, however, AVCC should always be within 1.8V - 5.5V.When
XT AL1
RESET
GND
(TQFP-64)
for timing details.
(1)
Pins
PE0
PE1
PB1
AVCC
VCC
+1.8V - 5.5V
+1.8V - 5.5V
I/O
O
I
I
(2)
ck
ck
>= 12MHz
>= 12MHz
Serial Data out
Serial Data in
Description
Serial Clock
350