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2513L–AVR–03/2013
ATmega162/V
Parallel
Programming
Enter Programming
Mode
The following algorithm puts the device in Parallel Programming mode:
1.
Apply 4.5 - 5.5V between V
CC and GND, and wait at least 100 s.
2.
Set RESET to “0” and toggle XTAL1 at least six times.
3.
ns.
4.
Apply 11.5 - 12.5V to RESET. Any activity on Prog_enable pins within 100 ns after +12V
has been applied to RESET, will cause the device to fail entering Programming mode.
Considerations for
Efficient Programming
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
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.
Table 104. Command Byte Bit Coding
Command Byte
Command Executed
1000 0000
Chip Erase
0100 0000
Write Fuse Bits
0010 0000
Write Lock Bits
0001 0000
Write Flash
0001 0001
Write EEPROM
0000 1000
Read Signature Bytes and Calibration byte
0000 0100
Read Fuse and Lock Bits
0000 0010
Read Flash
0000 0011
Read EEPROM
Table 105. No. of Words in a Page and no. of Pages in the Flash
Flash Size
Page Size
PCWORD
No. of Pages
PCPAGE
PCMSB
8K words (16K bytes)
64 words
PC[5:0]
128
PC[12:6]
12
Table 106. No. of Words in a Page and no. of Pages in the EEPROM
EEPROM Size
Page Size
PCWORD
No. of pages
PCPAGE
EEAMSB
512 bytes
4 bytes
EEA[1:0]
128
EEA[8:2]
8