ATMEga64L ATMEL Corporation, ATMEga64L Datasheet - Page 302

• Manufacturer Part Number: ATMEga64L
• Description: 8-bit AVR Microcontroller with 64K Bytes In-System Programmable Flash
• Manufacturer: ATMEL Corporation

Reading the EEPROM
Programming the Fuse Low
Bits
Programming the Fuse High
Bits
Programming the Extended
Fuse Bits
302
ATmega64(L)
The algorithm for reading the EEPROM memory is as follows (refer to “Programming the
Flash” on page 298 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 298 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 to “0” and BS2 to “0”.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
The algorithm for programming the Fuse High bits is as follows (refer to “Programming
the Flash” on page 298 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 to “1” and BS2 to “0”. This selects high data byte.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. Set BS1 to “0”. This selects low data byte.
The algorithm for programming the Extended Fuse bits is as follows (refer to “Program-
ming the Flash” on page 298 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 BS2 to “1” and BS1 to “0”. This selects extended data byte.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. Set BS2 to “0”. This selects low data byte.
DATA.
2490G–AVR–03/04