ATMEGA8L ATMEL [ATMEL Corporation], ATMEGA8L Datasheet - Page 228

• Manufacturer Part Number: ATMEGA8L
• Description: 8-bit AVR with 8K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Reading the Flash
Reading the EEPROM
Programming the Fuse Low
Bits
228
ATmega8(L)
Figure 107. Programming the EEPROM Waveforms
The algorithm for reading the Flash memory is as follows (refer to “Programming the
Flash” on page 225 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
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 225 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”.
The algorithm for programming the Fuse Low bits is as follows (refer to “Programming
the Flash” on page 225 for details on Command and Data loading):
1. A: Load Command “0100 0000”.
2. C: Load Data Low byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. Set BS1 and BS2 to “0”.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
RESET +12V
DATA.
DATA.
RDY/BSY
PAGEL
XTAL1
DATA
XA1
XA0
BS1
BS2
WR
OE
0x11
A
ADDR. HIGH
G
ADDR. LOW
B
DATA
C
E
XX
ADDR. LOW
B
DATA
C
K
XX
E
L
2486M–AVR–12/03