ATMEGA324A-PU Atmel, ATMEGA324A-PU Datasheet - Page 301

• Manufacturer Part Number: ATMEGA324A-PU
• Description: IC MCU AVR 32K 20MHZ 40PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA324A-PU

• 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: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Controller Family/series: Atmega
• No. Of I/o's: 32
• Eeprom Memory Size: 1KB
• Ram Memory Size: 2KB
• Cpu Speed: 20MHz
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

26.7
26.7.1
26.7.2
26.7.3
8272A–AVR–01/10
Parallel Programming
Enter Programming Mode
Considerations for Efficient Programming
Chip Erase
Table 26-13. Command Byte Bit Encoding
The following algorithm puts the device in parallel programming mode:
1. Apply 4.5 - 5.5V between V
2. Set RESET to “0” and toggle XTAL1 at least six times.
3. Set the Prog_enable pins listed in
4. Apply 11.5 - 12.5V to RESET. Any activity on Prog_enable pins within 100 ns after +12V
5. Wait at least 50 µs before sending a new command.
The loaded command and address are retained in the device during programming. For efficient
programming, the following should be considered.
• 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
• Address high byte needs only be loaded before programming or reading a new 256 word
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 EEPROM are
reprogrammed.
Note:
Load Command “Chip Erase”
164A/164PA/324A/324PA/644A/644PA/1284/1284P
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.
100 ns.
has been applied to RESET, will cause the device to fail entering programming mode.
Command Byte
1. The EEPRPOM memory is preserved during Chip Erase if the EESAVE Fuse is programmed.
1000 0000
0100 0000
0010 0000
0001 0000
0001 0001
0000 1000
0000 0100
0000 0010
0000 0011
Command Executed
Chip Erase
Write Fuse bits
Write Lock bits
Write Flash
Write EEPROM
Read Signature Bytes and Calibration byte
Read Fuse and Lock bits
Read Flash
Read EEPROM
CC
and GND.
Table 26-11 on page 300
(1)
memories plus Lock bits. The Lock bits are
to “0000” and wait at least
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