Datasheet

Table Of Contents
282
2570N–AVR–05/11
ATmega325/3250/645/6450
8. Power-off sequence (if needed):
Set RESET
to “1”.
Tur n V
CC
power off.
Figure 27-11. Serial Programming Waveforms
27.7.3 Serial Programming Instruction set
Table 27-15 and Figure 27-12 on page 284 describes the Instruction set.
Table 27-14. Minimum Wait Delay Before Writing the Next Flash or EEPROM Location
Symbol Minimum Wait Delay
t
WD_FUSE
4.5ms
t
WD_FLASH
4.5ms
t
WD_EEPROM
9.0ms
t
WD_ERASE
9.0ms
MSB
MSB
LSB
LSB
SERIAL CLOCK INPUT
(SCK)
SERIAL DATA INPUT
(MOSI)
(MISO)
SAMPLE
SERIAL DATA OUTPUT
Table 27-15. Serial Programming Instruction Set
Instruction/Operation
Instruction Format
Byte 1 Byte 2 Byte 3 Byte4
Programming Enable $AC $53 $00 $00
Chip Erase (Program Memory/EEPROM) $AC $80 $00 $00
Poll RDY/BSY
$F0 $00 $00 data byte out
Load Instructions
Load Extended Address byte
(1)
$4D $00 Extended adr $00
Load Program Memory Page, High byte $48 $00 adr LSB high data byte in
Load Program Memory Page, Low byte $40 $00 adr LSB low data byte in
Load EEPROM Memory Page (page access) $C1 $00 0000 00aa
/
0000 0aaa
data byte in
Read Instructions
Read Program Memory, High byte $28 adr MSB adr LSB high data byte out
Read Program Memory, Low byte $20 adr MSB adr LSB low data byte out
Read EEPROM Memory $A0 0000 00aa
/
0000 0aaa
aaaa aaaa data byte out