Datasheet

309
ATmega169A/PA/329A/PA/649A/P/3290A/PA/6490A/P [DATASHEET]
8284E–AVR–02/2013
the Write Program Memory Page instruction with the 8MSB of the address. If polling is not used, the user
must wait at least t
WD_FLASH
before issuing the next page. (See Table 28-15.) Accessing the serial program-
ming interface before the Flash write operation completes can result in incorrect programming.
5. A: The EEPROM array is programmed one byte at a time by supplying the address and data together with
the appropriate Write instruction. An EEPROM memory location is first automatically erased before new
data is written. If polling (RDY/BSY
) is not used, the user must wait at least t
WD_EEPROM
before issuing the
next byte (See Table 28-15.) In a chip erased device, no 0xFFs in the data file(s) need to be programmed.
B: The EEPROM array is programmed one page at a time. The Memory page is loaded one byte at a time
by supplying the 2 LSB of the address and data together with the Load EEPROM Memory Page instruction.
The EEPROM Memory Page is stored by loading the Write EEPROM Memory Page Instruction with the
4MSB of the address. When using EEPROM page access only byte locations loaded with the Load
EEPROM Memory Page instruction is altered. The remaining locations remain unchanged. If polling
(RDY/BSY
) is not used, the used must wait at least t
WD_EEPROM
before issuing the next page (See Table 28-
15). In a chip erased device, no 0xFF in the data file(s) need to be programmed.
6. Any memory location can be verified by using the Read instruction which returns the content at the selected
address at serial output MISO.
7. At the end of the programming session, RESET
can be set high to commence normal operation.
8. Power-off sequence (if needed):
Set RESET
to “1”.
Tur n V
CC
power off.
Figure 28-11. Serial programming waveforms.
28.8.3 Serial programming instruction set
Table 28-16 and Figure 28-12 on page 311 describes the Instruction set.
Table 28-15. 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
3.6ms
t
WD_ERASE
9.0ms
MSB
MSB
LSB
LSB
SERIAL CLOCK INPUT
(SCK)
SERIAL DATA INPUT
(MOSI)
(MISO)
SAMPLE
SERIAL DATA OUTPUT
Table 28-16. 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