Table 23 – Rainbow Electronics ATmega64C1 User Manual
Page 286
286
7647A–AVR–02/08
ATmega32/64/M1/C1
23.7.14
ATmega32/64/M1/C1 - 32K -Flash Boot Loader Parameters
In
, the parameters used in the description of the self program-
ming are given.
Note:
1. The different BOOTSZ Fuse configurations are shown in
2. 1 word equals 2 bytes.
For details about these two section, see
“NRWW – No Read-While-Write Section” on page 274
and
“RWW – Read-While-Write Section” on page 274
Note:
Z15:Z13: always ignored
Z0: should be zero for all SPM commands, byte select for the LPM instruction.
Table 23-7.
Boot Size Configuration, ATmega32/64/M1/C1 (32K product)
BOOTSZ1
BOOTSZ0
Boot
Size
(2)
Pages
Application
Flash
Section
Boot
Loader
Flash
Section
End
Application
Section
Boot Reset
Address
(Start Boot
Loader
Section)
1
1
256
words
4
0x0000 -
0x3EFF
0x3F00 -
0x3FFF
0x3EFF
0x3F00
1
0
512
words
8
0x0000 -
0x3DFF
0x3E00 -
0x3FFF
0x3DFF
0x3E00
0
1
1024
words
16
0x0000 -
0x3BFF
0x3C00 -
0x3FFF
0x3BFF
0x3C00
0
0
2048
words
32
0x0000 -
0x37FF
0x3800 -
0x3FFF
0x37FF
0x3800
Table 23-8.
Read-While-Write Limit
Section
Pages
Address
Read-While-Write section (RWW)
224
0x0000 - 0x37FF
No Read-While-Write section (NRWW)
32
0x3800 - 0x3FFF
Table 23-9.
Explanation of Different Variables used in
and the Mapping to the Z-
pointer
Variable
Corresponding
Z-value
Description
PCMSB
13
Most significant bit in the Program Counter. (The Program
Counter is 14 bits PC[13:0])
PAGEMSB
5
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
Z14
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[13:6]
Z14: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)