ATmega128A Atmel Corporation, ATmega128A Datasheet - Page 297

• Manufacturer Part Number: ATmega128A
• Manufacturer: Atmel Corporation

Specifications of ATmega128A

• Flash (kbytes): 128 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 53
• Ext Interrupts: 8
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 8
• Input Capture Channels: 2
• Pwm Channels: 7
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

26.6.2
26.6.3
26.6.4
8151H–AVR–02/11
Considerations for Efficient Programming
Chip Erase
Programming the Flash
Note, if External Crystal or External RC configuration is selected, it may not be possible to apply
qualified XTAL1 pulses. In such cases, the following algorithm should be followed:
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
are 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”
The Flash is organized in pages, see
the program data is latched into a page buffer. This allows one page of program data to be pro-
grammed simultaneously. The following procedure describes how to program the entire Flash
memory:
A. Load Command “Write Flash”
1. Set Prog_enable pins listed in
2. Apply 4.5V - 5.5V between V
3. Wait 100 µs.
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 0b0.
6. Entering Programming mode with the original algorithm, as described above.
• The command needs only be loaded once when writing or reading multiple memory
• Skip writing the data value $FF, that is the contents of the entire EEPROM (unless the
• Address high byte needs only be loaded before programming or reading a new 256 word
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.
1. Set XA1, XA0 to “10”. This enables command loading.
2. Set BS1 to “0”.
locations.
EESAVE fuse is programmed) and Flash after a Chip Erase.
window in Flash or 256-byte EEPROM. This consideration also applies to Signature bytes
reading.
RESET.
(CKSEL3:0 = 0b0000) If Lock bits are programmed, a Chip Erase command must be
executed before changing the fuses.
The EEPRPOM memory is preserved during chip erase if the EESAVE fuse is programmed.
CC
Table on page 295
and GND simultaneously as 11.5V - 12.5V is applied to
Table 26-10 on page
(Note:)
to “0000”.
memories plus Lock bits. The Lock bits
296. When programming the Flash,
ATmega128A
297