Atmel ATmega48PV User Manual

289
8025I–AVR–02/09
ATmega48P/88P/168P/328P
24.8.14 ATmega88P Boot Loader Parameters
In Table 24-7 through Table 24-9, the parameters used in the description of the self programming are given.
Note: The different BOOTSZ Fuse configurations are shown in Figure 24-2 on page 280.
For details about these two section, see ”NRWW – No Read-While-Write Section” on page 278 and ”RWW – Read-While-
Write Section” on page 278
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 282 for details about the use of Z-pointer during Self-
Programming.
Table 24-7. Boot Size Configuration, ATmega88P
BOOTSZ1 BOOTSZ0
Boot
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
Table 24-8. 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
Table 24-9. Explanation of Different Variables used in Figure 24-3 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])
PAG EM SB 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)

Atmel ATmega48PV Specifications

General

Brand	Atmel
Model	ATmega48PV
Category	Microcontrollers
Language	English