Datasheet

289
2545T–AVR–05/11
ATmega48/88/168
28.5 Page size
28.6 Parallel programming parameters, pin mapping, and commands
This section describes how to parallel program and verify Flash Program memory, EEPROM
Data memory, Memory Lock bits, and Fuse bits in the ATmega48/88/168. Pulses are assumed
to be at least 250ns unless otherwise noted.
28.6.1 Signal names
In this section, some pins of the ATmega48/88/168 are referenced by signal names describing
their functionality during parallel programming, see Figure 28-1 on page 290 and Table 28-11 on
page 290. Pins not described in Table 28-11 on page 290 are referenced by pin names.
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a positive pulse.
The bit coding is shown in Table 28-13 on page 291.
When pulsing WR
or OE, the command loaded determines the action executed. The different
Commands are shown in Table 28-14 on page 291.
Table 28-9. No. of words in a page and no. of pages in the flash.
Device Flash size Page size PCWORD
No. of
pages PCPAGE PCMSB
Atmel
ATmega48
2K words
(4Kbytes)
32 words PC[4:0] 64 PC[10:5] 10
Atmel
ATmega88
4K words
(8Kbytes)
32 words PC[4:0] 128 PC[11:5] 11
Atmel
ATmega168
8K words
(16Kbytes)
64 words PC[5:0] 128 PC[12:6] 12
Table 28-10. No. of words in a page and no. of pages in the EEPROM.
Device
EEPROM
size
Page
size PCWORD
No. of
pages PCPAGE EEAMSB
ATmega48 256 bytes 4 bytes EEA[1:0] 64 EEA[7:2] 7
ATmega88 512 bytes 4 bytes EEA[1:0] 128 EEA[8:2] 8
ATmega168 512 bytes 4 bytes EEA[1:0] 128 EEA[8:2] 8