ATMEGA88P_14 Datasheet, PDF (287/420 Pages) ATMEL Corporation – High Endurance Non-volatile Memory Segments

ATmega48P/88P/168P
27.8.14 ATmega88P Boot Loader Parameters
In Table 27-7 through Table 27-9, the parameters used in the description of the self programming are given.
Table 27-7. Boot Size Configuration, ATmega88P
Boot
BOOTSZ1 BOOTSZ0 Size
Pages
Application
Flash
Section
Boot
Loader
Flash
Section
End
Application
Section
Boot Reset Address (Start Boot Loader
Section)
1
1
128 words
4 0x000 - 0xF7F 0xF80 - 0xFFF 0xF7F
0xF80
1
0
256 words
8 0x000 - 0xEFF 0xF00 - 0xFFF 0xEFF
0xF00
0
1
512 words
16 0x000 - 0xDFF 0xE00 - 0xFFF 0xDFF
0xE00
0
0
1024 words
32 0x000 - 0xBFF 0xC00 - 0xFFF 0xBFF
0xC00
Note: The different BOOTSZ Fuse configurations are shown in Figure 27-2 on page 278.
Table 27-8. Read-While-Write Limit, ATmega88P
Section
Pages
Address
Read-While-Write section (RWW)
96
0x000 - 0xBFF
No Read-While-Write section (NRWW)
32
0xC00 - 0xFFF
For details about these two section, see ”NRWW – No Read-While-Write Section” on page 276 and ”RWW – Read-While-
Write Section” on page 276
Table 27-9. Explanation of Different Variables used in Figure 27-3 and the Mapping to the Z-pointer, ATmega88P
Variable
Corresponding
Z-value⁽¹⁾
Description
PCMSB
11
Most significant bit in the Program Counter. (The Program Counter is
12 bits PC[11:0])
PAGEMSB
4
Most significant bit which is used to address the words within one
page (32 words in a page requires 5 bits PC [4:0]).
ZPCMSB
Z12
Bit in Z-register that is mapped to PCMSB. Because Z0 is not used,
the ZPCMSB equals PCMSB + 1.
ZPAGEMSB
Z5
Bit in Z-register that is mapped to PAGEMSB. Because Z0 is not
used, the ZPAGEMSB equals PAGEMSB + 1.
PCPAGE
PC[11:5]
Z12:Z6
Program counter page address: Page select, for page erase and
page write
PCWORD
PC[4:0]
Z5:Z1
Program counter word address: Word select, for filling temporary
buffer (must be zero during page write operation)
Note:
1. Z15:Z13: always ignored
Z0: should be zero for all SPM commands, byte select for the LPM instruction.
See ”Addressing the Flash During Self-Programming” on page 280 for details about the use of Z-pointer during Self-
Programming.
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