
498
42073A-MCU Wireless-02/13
ATmega2564/1284/644RFR2
30.6.16 Boot Loader Parameters for 256 kByte of Flash Memory
description of the Self-Programming are given.
Table 30-11. Read-While-Write Limit with 256 kByte of Flash Memory
Section
(0)
Pages
Address
Read-While-Write section (RWW)
992
0x00000 – 0x1EFFF
No Read-While-Write section (NRWW)
32
0x1F000 – 0x1FFFF
Note:
Table 30-12.
the mapping to the Z-pointer for 256 kByte of Flash Memory
Variable
Value
Corresponding
Z-value
(0)
Description
(0)
PCMSB
16
Most significant bit in the Program Counter.
(The Program Counter is 16 bits PC[15:0])
PAGEMSB
6
Most significant bit which is used to address
the words within one page (128 words in a
page requires seven bits PC [6:0]).
ZPCMSB
Z17:Z16
(3)
Bit in Z-pointer that is mapped to PCMSB.
Because Z0 is not used, the ZPCMSB
equals PCMSB + 1.
ZPAGEMSB
Z7
Bit in Z-pointer that is mapped to PCMSB.
Because Z0 is not used; the ZPAGEMSB
equals PAGEMSB + 1.
PCPAGE
PC[16:7]
Z17
(3):Z8
Program Counter page address: Page
select, for Page Erase and Page Write.
PCWORD
PC[6:0]
Z7:Z1
Program Counter word address: Word
select, for filling temporary buffer (must be
zero during Page Write operation)
Notes:
1. Z0: should be zero for all SPM commands, byte select for the (E)LPM instruction.
about the use of Z-pointer during Self-Programming.
3. The Z-register is only 16 bits wide. Bit [17:16] are located in the RAMPZ register
in the I/O map.
Table 30-13. Boot Size Configuration with 256 kByte of Flash Memory
(0)
B
O
T
S
Z
1
B
O
T
S
Z
0
B
o
t
S
iz
e
P
a
g
e
s
A
p
li
c
a
ti
o
n
F
la
s
h
S
e
c
ti
o
n
B
o
t
L
o
a
d
e
r
F
la
s
h
S
e
c
ti
o
n
E
n
d
A
p
li
c
a
ti
o
n
S
e
c
ti
o
n
B
o
t
R
e
s
e
t
A
d
re
s
(S
ta
rt
B
o
t
L
o
a
d
e
r
S
e
c
ti
o
n
)
1
512
words
4
0x00000 –
0x1FDFF
0x1FE00 –
0x1FFFF
0x1FDFF
0x1FE00
1
0
1024
words
8
0x00000 –
0x1FBFF
0x1FC00 –
0x1FFFF
0x1FBFF
0x1FC00