ATmega644P Atmel Corporation, ATmega644P Datasheet - Page 294

• Manufacturer Part Number: ATmega644P
• Manufacturer: Atmel Corporation

Specifications of ATmega644P

• Flash (kbytes): 64 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• 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): 4
• Eeprom (bytes): 2048
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• 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: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

24.2
8011O–AVR–07/10
Fuse Bits
Table 24-2.
Notes:
The ATmega164P/324P/644P has four Fuse bytes.
functionality of all the fuses and how they are mapped into the Fuse bytes. Note that the fuses
are read as logical zero, “0”, if they are programmed.
Table 24-3.
Note:
–
–
–
–
–
BODLEVEL2
BODLEVEL1
BODLEVEL0
BLB1 Mode
Fuse Low Byte
1
2
3
4
1. Program the Fuse bits and Boot Lock bits before programming the LB1 and LB2.
2. “1” means unprogrammed, “0” means programmed
1. See
Memory Lock Bits
(1)
(1)
(1)
Lock Bit Protection Modes
Extended Fuse Byte
”System and Reset Characteristics” on page 331
BLB12
1
1
0
0
7
6
5
4
3
2
1
0
Bit No
BLB11
1
0
0
1
Description
–
–
–
–
–
Brown-out Detector trigger level
Brown-out Detector trigger level
Brown-out Detector trigger level
Protection Type
No restrictions for SPM or (E)LPM accessing the Boot Loader
section.
SPM is not allowed to write to the Boot Loader section.
SPM is not allowed to write to the Boot Loader section, and
(E)LPM executing from the Application section is not allowed to
read from the Boot Loader section. If Interrupt Vectors are
placed in the Application section, interrupts are disabled while
executing from the Boot Loader section.
(E)LPM executing from the Application section is not allowed to
read from the Boot Loader section. If Interrupt Vectors are
placed in the Application section, interrupts are disabled while
executing from the Boot Loader section.
(1)(2)
(Continued)
ATmega164P/324P/644P
Table 24-3
for BODLEVEL Fuse decoding.
-
Table 24-5
Default Value
1
1
1
1
1
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
describe briefly the
294