ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 265

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

Reading the Flash
Reading the EEPROM
2570A–AVR–09/04
K: Repeat 3 through 5 until the entire buffer is filled.
L: Program EEPROM page
1. Set BS1 to “0”.
2. Give WR a negative pulse. This starts programming of the EEPROM page.
3. Wait until to RDY/BSY goes high before programming the next page (See Figure
Figure 114. Programming the EEPROM Waveforms
The algorithm for reading the Flash memory is as follows (refer to “Programming the
Flash” on page 262 for details on Command and Address loading):
1. A: Load Command “0000 0010”.
2. G: Load Address High Byte (0x00 - 0xFF).
3. B: Load Address Low Byte (0x00 - 0xFF).
4. Set OE to “0”, and BS1 to “0”. The Flash word low byte can now be read at DATA.
5. Set BS1 to “1”. The Flash word high byte can now be read at DATA.
6. Set OE to “1”.
The algorithm for reading the EEPROM memory is as follows (refer to “Programming the
Flash” on page 262 for details on Command and Address loading):
1. A: Load Command “0000 0011”.
2. G: Load Address High Byte (0x00 - 0xFF).
3. B: Load Address Low Byte (0x00 - 0xFF).
4. Set OE to “0”, and BS1 to “0”. The EEPROM Data byte can now be read at
5. Set OE to “1”.
RESET +12V
RDY/BSY
PAGEL
RDY/BSY goes low.
114 for signal waveforms).
DATA.
XTAL1
DATA
XA1
XA0
BS1
BS2
WR
OE
0x11
A
ADDR. HIGH
G
ADDR. LOW
B
DATA
C
ATmega325/3250/645/6450
XX
E
ADDR. LOW
B
DATA
C
K
XX
E
L
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