ATMEGA644P-20PQ Atmel, ATMEGA644P-20PQ Datasheet - Page 278

• Manufacturer Part Number: ATMEGA644P-20PQ
• Description: MCU AVR 64K FLASH 20MHZ 40-PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-20PQ

• 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: 40-DIP (0.600", 15.24mm)
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8011O–AVR–07/10
Figure 23-1. Read-While-Write vs. No Read-While-Write
Z-pointer
Addresses RWW
Section
Code Located in
NRWW Section
Can be Read During
the Operation
Read-While-Write
No Read-While-Write
(RWW) Section
(NRWW) Section
ATmega164P/324P/644P
Z-pointer
Addresses NRWW
Section
CPU is Halted
During the Operation
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