ATMEGA8-16PC Atmel, ATMEGA8-16PC Datasheet - Page 221

• Manufacturer Part Number: ATMEGA8-16PC
• Description: IC AVR MCU 8K 16MHZ COM 28-DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8-16PC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• 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): 4.5 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: ATMEGA816PC

Parallel
Programming
Enter Programming
Mode
Considerations for
Efficient Programming
Chip Erase
2486Z–AVR–02/11
The following algorithm puts the device in Parallel Programming mode:
1. Apply 4.5V - 5.5V between V
2. Set RESET to “0” and toggle XTAL1 at least 6 times
3. Set the Prog_enable pins listed in
4. Apply 11.5V - 12.5V to RESET. Any activity on Prog_enable pins within 100ns after +12V
Note, if the RESET pin is disabled by programming the RSTDISBL Fuse, it may not be possible
to follow the proposed algorithm above. The same may apply when External Crystal or External
RC configuration is selected because it is not possible to apply qualified XTAL1 pulses. In such
cases, the following algorithm should be followed:
1. Set Prog_enable pins listed in
2. Apply 4.5V - 5.5V between V
3. Wait 100ns
4. Re-program the fuses to ensure that External Clock is selected as clock source
5. Exit Programming mode by power the device down or by bringing RESET pin to 0’b0
6. Entering Programming mode with the original algorithm, as described above
The loaded command and address are retained in the device during programming. For efficient
programming, the following should be considered.
•
•
•
The Chip Erase will erase the Flash and EEPROM
not reset until the Program memory has been completely erased. The Fuse Bits are not
changed. A Chip Erase must be performed before the Flash and/or the EEPROM are
reprogrammed.
Note:
Load Command “Chip Erase”
1. Set XA1, XA0 to “10”. This enables command loading
2. Set BS1 to “0”
3. Set DATA to “1000 0000”. This is the command for Chip Erase
4. Give XTAL1 a positive pulse. This loads the command
5. Give WR a negative pulse. This starts the Chip Erase. RDY/BSY goes low
6. Wait until RDY/BSY goes high before loading a new command
100ns
has been applied to RESET, will cause the device to fail entering Programming mode
RESET
(CKSEL3:0 = 0’b0000) and RESET pin is activated (RSTDISBL unprogrammed). If Lock
Bits are programmed, a chip erase command must be executed before changing the
fuses
The command needs only be loaded once when writing or reading multiple memory
locations
Skip writing the data value 0xFF, that is the contents of the entire EEPROM (unless the
EESAVE Fuse is programmed) and Flash after a Chip Erase
Address High byte needs only be loaded before programming or reading a new 256 word
window in Flash or 256 byte EEPROM. This consideration also applies to Signature bytes
reading
1. The EEPRPOM memory is preserved during chip erase if the EESAVE Fuse is programmed
CC
CC
Table 92 on page 220
and GND, and wait at least 100µs
and GND simultaneously as 11.5V - 12.5V is applied to
Table 92 on page 220
(1)
memories plus Lock Bits. The Lock Bits are
to “0000”
to “0000” and wait at least
ATmega8(L)
221