ATMEGA88-20PU Atmel, ATMEGA88-20PU Datasheet - Page 296

• Manufacturer Part Number: ATMEGA88-20PU
• Description: IC AVR MCU 8K 20MHZ 5V 28DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA88-20PU

• 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: 8KB (4K 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)
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SPI/TWI/USART
• Total Internal Ram Size: 1KB
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 6-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Through Hole
• Pin Count: 28
• Package Type: PDIP
• Processor Series: ATMEGA8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 23
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRTS2080A, ATASTK512-EK1-IND
• Minimum Operating Temperature: - 40 C
• Package: 28PDIP
• Family Name: ATmega
• Maximum Speed: 20 MHz
• For Use With: ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

27.7.11
27.7.12
27.7.13
296
ATmega48/88/168
Programming the Lock Bits
Reading the Fuse and Lock Bits
Reading the Signature Bytes
The algorithm for programming the Lock bits is as follows (refer to
page 291
1. A: Load Command “0010 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs the Lock bit. If LB mode 3 is programmed
3. Give WR a negative pulse and wait for RDY/BSY to go high.
The Lock bits can only be cleared by executing Chip Erase.
The algorithm for reading the Fuse and Lock bits is as follows (refer to
on page 291
1. A: Load Command “0000 0100”.
2. Set OE to “0”, BS2 to “0” and BS1 to “0”. The status of the Fuse Low bits can now be
3. Set OE to “0”, BS2 to “1” and BS1 to “1”. The status of the Fuse High bits can now be
4. Set OE to “0”, BS2 to “1”, and BS1 to “0”. The status of the Extended Fuse bits can now
5. Set OE to “0”, BS2 to “0” and BS1 to “1”. The status of the Lock bits can now be read at
6. Set OE to “1”.
Figure 27-6. Mapping Between BS1, BS2 and the Fuse and Lock Bits During Read
The algorithm for reading the Signature bytes is as follows (refer to
page 291
1. A: Load Command “0000 1000”.
2. B: Load Address Low Byte (0x00 - 0x02).
3. Set OE to “0”, and BS1 to “0”. The selected Signature byte can now be read at DATA.
4. Set OE to “1”.
(LB1 and LB2 is programmed), it is not possible to program the Boot Lock bits by any
External Programming mode.
read at DATA (“0” means programmed).
read at DATA (“0” means programmed).
be read at DATA (“0” means programmed).
DATA (“0” means programmed).
for details on Command and Data loading):
for details on Command and Address loading):
for details on Command loading):
Extended Fuse Byte
Fuse Low Byte
Fuse High Byte
Lock Bits
BS2
BS2
0
1
0
1
BS1
0
1
“Programming the Flash” on
“Programming the Flash” on
“Programming the Flash”
DATA
2545S–AVR–07/10