ATMEGA168-20PI Atmel, ATMEGA168-20PI Datasheet - Page 295

• Manufacturer Part Number: ATMEGA168-20PI
• Description: IC AVR MCU 16K 20MHZ 28DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA168-20PI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

27.7.8
27.7.9
27.7.10
2545S–AVR–07/10
Programming the Fuse Low Bits
Programming the Fuse High Bits
Programming the Extended Fuse Bits
The algorithm for programming the Fuse Low bits is as follows (refer to
on page 291
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. 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
Flash” on page 291
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
Flash” on page 291
1. 1. A: Load Command “0100 0000”.
2. 2. C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. 3. Set BS1 to “0” and BS2 to “1”. This selects extended data byte.
4. 4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. 5. Set BS2 to “0”. This selects low data byte.
Figure 27-5. Programming the FUSES Waveforms
RESET +12V
RDY/BSY
PAGEL
XTAL1
DATA
BS2
XA1
XA0
BS1
WR
OE
for details on Command and Data loading):
0x40
A
DATA
for details on Command and Data loading):
for details on Command and Data loading):
C
Write Fuse Low byte
XX
0x40
A
DATA
C
Write Fuse high byte
XX
ATmega48/88/168
0x40
A
“Programming the Flash”
DATA
C
“Programming the
“Programming the
Write Extended Fuse byte
XX
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