ATMEGA16 Datasheet, PDF (252/315 Pages) ATMEL Corporation – 8-bit AVR Microcontroller with 16K Bytes In-System Programmable Flash

ATmega16 Boot Loader
Parameters
In Table 99 through Table 101, the parameters used in the description of the self pro-
gramming are given.
Table 99. Boot Size Configuration⁽¹⁾
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
2
$0000 -
$1F7F
$1F80 -
$1FFF
$1F7F
$1F80
1
0
256
words
4
$0000 -
$1EFF
$1F00 -
$1FFF
$1EFF
$1F00
0
1
512
words
8
$0000 -
$1DFF
$1E00 -
$1FFF
$1DFF
$1E00
0
0
1024
words
16
$0000 -
$1BFF
$1C00 -
$1FFF
$1BFF
$1C00
Note: 1. The different BOOTSZ Fuse configurations are shown in Figure 125
Table 100. Read-While-Write Limit⁽¹⁾
Section
Pages Address
Read-While-Write section (RWW)
112
$0000 - $1BFF
No Read-While-Write section (NRWW)
16
$1C00 - $1FFF
Note: 1. For details about these two section, see “NRWW – No Read-While-Write Section” on
page 242 and “RWW – Read-While-Write Section” on page 242
Table 101. Explanation of Different Variables used in Figure 126 and the Mapping to
the Z-pointer
Variable
Corresponding
Z-value⁽¹⁾
Description
PCMSB
12
Most significant bit in the Program Counter.
(The Program Counter is 13 bits PC[12:0])
5
PAGEMSB
Most significant bit which is used to address the
words within one page (64 words in a page
requires 6 bits PC [5:0]).
ZPCMSB
Z13
Bit in Z-register that is mapped to PCMSB.
Because Z0 is not used, the ZPCMSB equals
PCMSB + 1.
ZPAGEMSB
Z6
Bit in Z-register that is mapped to PAGEMSB.
Because Z0 is not used, the ZPAGEMSB
equals PAGEMSB + 1.
PCPAGE
PC[12:6]
Z13:Z7
Program Counter page address: Page select,
for Page Erase and Page Write
PCWORD
PC[5:0]
Z6:Z1
Program Counter word address: Word select,
for filling temporary buffer (must be zero during
page write operation)
Note: 1. Z15:Z14: always ignored
Z0: should be zero for all SPM commands, byte select for the LPM instruction.
252 ATmega16(L)
2466E–AVR–10/02