Datasheet

191
8246B–AVR–09/11
ATtiny2313A/4313
• B: Load Address Low Byte (0x00 - 0xFF).
•Set OE
to “0”, and BS1 to “0”. The EEPROM Data byte can now be read at DATA.
•Set OE
to “1”.
21.2.8 Programming Low Fuse Bits
The algorithm for programming the low fuse bits is as follows (see “Programming the Flash” on
page 187 for details on command and data loading):
• A: Load Command “0100 0000”.
• C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
•Give WR
a negative pulse and wait for RDY/BSY to go high.
21.2.9 Programming High Fuse Bits
The algorithm for programming the high fuse bits is as follows (see “Programming the Flash” on
page 187 for details on command and data loading):
• A: Load Command “0100 0000”.
• C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
• Set BS1 to “1” and BS2 to “0”. This selects high data byte.
•Give WR
a negative pulse and wait for RDY/BSY to go high.
• Set BS1 to “0”. This selects low data byte.
21.2.10 Programming Extended Fuse Bits
The algorithm for programming the extended fuse bits is as follows (see “Programming the
Flash” on page 187 for details on command and data loading):
• A: Load Command “0100 0000”.
• C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
• Set BS1 to “0” and BS2 to “1”. This selects extended data byte.
•Give WR
a negative pulse and wait for RDY/BSY to go high.
• Set BS2 to “0”. This selects low data byte.
Fuse programming waveforms are illustrated in Figure 21-5, where XX means “don’t care” and
letters refer to the programming steps described above.