ATmega644 Atmel Corporation, ATmega644 Datasheet - Page 287

• Manufacturer Part Number: ATmega644
• Manufacturer: Atmel Corporation

Specifications of ATmega644

• 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: 1
• 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: 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: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

25.2.1
25.3
25.4
25.5
Table 25-7.
Table 25-8.
25.6
25.6.1
2593N–AVR–07/10
ATmega644
ATmega644
Device
Device
Signature Bytes
Calibration Byte
Page Size
Parallel Programming Parameters, Pin Mapping, and Commands
Latching of Fuses
Signal Names
No. of Words in a Page and No. of Pages in the Flash
No. of Words in a Page and No. of Pages in the EEPROM
32K words (64 Kbytes)
EEPROM Size
Flash Size
The fuse values are latched when the device enters programming mode and changes of the
fuse values will have no effect until the part leaves Programming mode. This does not apply to
the EESAVE Fuse which will take effect once it is programmed. The fuses are also latched on
Power-up in Normal mode.
All Atmel microcontrollers have a three-byte signature code which identifies the device. This
code can be read in both serial and parallel mode, also when the device is locked. The three
bytes reside in a separate address space. The ATmega644 signature bytes are given in
25-6.
Table 25-6.
The ATmega644 has a byte calibration value for the internal RC Oscillator. This byte resides in
the high byte of address 0x000 in the signature address space. During reset, this byte is auto-
matically written into the OSCCAL Register to ensure correct frequency of the calibrated RC
Oscillator.
This section describes how to parallel program and verify Flash Program memory, EEPROM
Data memory, Memory Lock bits, and Fuse bits in the ATmega644. Pulses are assumed to be at
least 250 ns unless otherwise noted.
In this section, some pins of the ATmega644 are referenced by signal names describing their
functionality during parallel programming, see
the following table are referenced by pin names.
2 Kbytes
Part
ATmega644
Device and JTAG ID
Page Size
128 words
Page Size
0x000
8 bytes
0x1E
Signature Bytes Address
0x001
0x96
PCWORD
PCWORD
EEA[2:0]
PC[6:0]
0x002
Figure 25-1
0x09
No. of Pages
No. of Pages
256
256
Part Number
and
9609
Table
EEA[10:3]
PCPAGE
PCPAGE
PC[14:7]
25-9. Pins not described in
JTAG
ATmega644
Manufacture ID
0x1F
EEAMSB
PCMSB
14
10
Table
287