ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 264

• Manufacturer Part Number: ATMEGA325-16AJ
• Description: 8-bit Microcontroller with In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Programming the EEPROM
264
ATmega325/3250/645/6450
Figure 112. Addressing the Flash Which is Organized in Pages
Note:
Figure 113. Programming the Flash Waveforms
Note:
The EEPROM is organized in pages, see Table 117 on page 261. When programming
the EEPROM, the program data is latched into a page buffer. This allows one page of
data to be programmed simultaneously. The programming algorithm for the EEPROM
data memory is as follows (refer to “Programming the Flash” on page 262 for details on
Command, Address and Data loading):
1. A: Load Command “0001 0001”.
2. G: Load Address High Byte (0x00 - 0xFF).
3. B: Load Address Low Byte (0x00 - 0xFF).
4. C: Load Data (0x00 - 0xFF).
5. E: Latch data (give PAGEL a positive pulse).
RESET +12V
RDY/BSY
PAGEL
XTAL1
DATA
XA1
XA0
BS1
BS2
WR
OE
PROGRAM MEMORY
1. PCPAGE and PCWORD are listed in Table 116 on page 261.
1. “XX” is don’t care. The letters refer to the programming description above.
PROGRAM
COUNTER
PAGE
0x10
A
PAGE ADDRESS
WITHIN THE FLASH
ADDR. LOW
B
PCMSB
DATA LOW
C
PCPAGE
DATA HIGH
D
XX
E
PAGEMSB
ADDR. LOW
PCWORD
B
WORD ADDRESS
WITHIN A PAGE
DATA LOW
C
(1)
F
DATA HIGH
INSTRUCTION WORD
D
PAGE
XX
E
ADDR. HIGH
G
(1)
H
PCWORD[PAGEMSB:0]:
XX
00
01
02
PAGEEND
2570A–AVR–09/04