ATMEGA644P-20AQ Atmel, ATMEGA644P-20AQ Datasheet - Page 301

• Manufacturer Part Number: ATMEGA644P-20AQ
• Description: MCU AVR 64K FLASH 20MHZ 44-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-20AQ

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• 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: 44-TQFP, 44-VQFP
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8011O–AVR–07/10
3. Set DATA = Address extended high byte (0x00 - 0xFF).
4. Give XTAL1 a positive pulse. This loads the address high byte.
I. Program Page
1. Set BS2, BS1 to “00”
2. Give WR a negative pulse. This starts programming of the entire page of data. RDY/BSY
3. Wait until RDY/BSY goes high (See
J. Repeat B through I until the entire Flash is programmed or until all data has been
programmed.
K. End Page Programming
1. 1. Set XA1, XA0 to “10”. This enables command loading.
2. Set DATA to “0000 0000”. This is the command for No Operation.
3. Give XTAL1 a positive pulse. This loads the command, and the internal write signals are
Figure 24-2. Addressing the Flash Which is Organized in Pages
Note:
goes low.
reset.
1. PCPAGE and PCWORD are listed in
PROGRAM MEMORY
PROGRAM
COUNTER
PAGE
PAGE ADDRESS
WITHIN THE FLASH
PCMSB
PCPAGE
Figure 24-3 on page 302
PAGEMSB
PCWORD
Table 24-7 on page
WORD ADDRESS
WITHIN A PAGE
ATmega164P/324P/644P
INSTRUCTION WORD
PAGE
296.
for signal waveforms).
(1)
PCWORD[PAGEMSB:0]:
00
01
02
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