ATMEGA644PA-AUR Atmel, ATMEGA644PA-AUR Datasheet - Page 25
ATMEGA644PA-AUR
Manufacturer Part Number
ATMEGA644PA-AUR
Description
IC MCU AVR 64K FLASH 44TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA644PA-AUR
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)
1.8 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
44-TQFP, 44-VQFP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ATMEGA644PA-AUR
Manufacturer:
ATMEL
Quantity:
1 400
Part Number:
ATMEGA644PA-AUR
Manufacturer:
MICROCHIP/微芯
Quantity:
20 000
- Current page: 25 of 581
- Download datasheet (27Mb)
8272A–AVR–01/10
operations. The Programming times for the different modes are shown in
While EEPE is set, any write to EEPMn will be ignored. During reset, the EEPMn bits will be
reset to 0b00 unless the EEPROM is busy programming.
Table 7-1.
• Bit 3 – EERIE: EEPROM Ready Interrupt Enable
Writing EERIE to one enables the EEPROM Ready Interrupt if the I bit in SREG is set. Writing
EERIE to zero disables the interrupt. The EEPROM Ready interrupt generates a constant inter-
rupt when EEPE is cleared.
• Bit 2 – EEMPE: EEPROM Master Programming Enable
The EEMPE bit determines whether setting EEPE to one causes the EEPROM to be written.
When EEMPE is set, setting EEPE within four clock cycles will write data to the EEPROM at the
selected address If EEMPE is zero, setting EEPE will have no effect. When EEMPE has been
written to one by software, hardware clears the bit to zero after four clock cycles. See the
description of the EEPE bit for an EEPROM write procedure.
• Bit 1 – EEPE: EEPROM Programming Enable
The EEPROM Write Enable Signal EEPE is the write strobe to the EEPROM. When address
and data are correctly set up, the EEPE bit must be written to one to write the value into the
EEPROM. The EEMPE bit must be written to one before a logical one is written to EEPE, other-
wise no EEPROM write takes place. The following procedure should be followed when writing
the EEPROM (the order of steps 3 and 4 is not essential):
1. Wait until EEPE becomes zero.
2. Wait until SPMEN in SPMCSR becomes zero.
3. Write new EEPROM address to EEAR (optional).
4. Write new EEPROM data to EEDR (optional).
5. Write a logical one to the EEMPE bit while writing a zero to EEPE in EECR.
6. Within four clock cycles after setting EEMPE, write a logical one to EEPE.
The EEPROM can not be programmed during a CPU write to the Flash memory. The software
must check that the Flash programming is completed before initiating a new EEPROM write.
Step 2 is only relevant if the software contains a Boot Loader allowing the CPU to program the
Flash. If the Flash is never being updated by the CPU, step 2 can be omitted. See
gramming” on page 295
Caution: An interrupt between step 5 and step 6 will make the write cycle fail, since the
EEPROM Master Write Enable will time-out. If an interrupt routine accessing the EEPROM is
interrupting another EEPROM access, the EEAR or EEDR Register will be modified, causing the
interrupted EEPROM access to fail. It is recommended to have the Global Interrupt Flag cleared
during all the steps to avoid these problems.
164A/164PA/324A/324PA/644A/644PA/1284/1284P
EEPM1
0
0
1
1
EEPM0
EEPROM Mode Bits
0
1
0
1
Programming
for details about Boot programming.
3.4 ms
1.8 ms
1.8 ms
Time
–
Erase and Write in one operation (Atomic Operation)
Erase Only
Write Only
Operation
Reserved for future use
Table 7-1 on page
”Memory Pro-
25.
25
Related parts for ATMEGA644PA-AUR
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 44-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 40DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64K FLASH 20MHZ 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64K FLASH 20MHZ 44QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
Atmega644 8-bit Avr Microcontroller With 64k Bytes In-system Programmable Flash
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64-QFN
Manufacturer:
Atmel
Datasheet: