Table 30-6, Table 30-7 on, Atmega128rfa1 – Rainbow Electronics ATmega128RFA1 User Manual
Page 461
461
8266A-MCU Wireless-12/09
ATmega128RFA1
Table 30-6. Explanation of different variables used in
and the
mapping to the Z-pointer for 128kByte of Flash Memory
Variable
Value
Corresponding
Z-value
(2)
Description
(1)
PCMSB
15
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
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[15:7]
Z16
(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.
2. See
"Addressing the Flash During Self-Programming" on page 453
about the use of Z-pointer during Self-Programming.
3. The Z-register is only 16 bits wide. Bit 16 is located in the RAMPZ register in the
I/O map.
Table 30-7. Boot Size Configuration with 128kByte of Flash Memory
(
1
)
B
O
O
T
S
Z
1
B
O
O
T
S
Z
0
B
o
o
t
S
iz
e
P
a
g
e
s
A
p
p
li
c
a
ti
o
n
F
la
s
h
S
e
c
ti
o
n
B
o
o
t
L
o
a
d
e
r
F
la
s
h
S
e
c
ti
o
n
E
n
d
A
p
p
li
c
a
ti
o
n
S
e
c
ti
o
n
B
o
o
t
R
e
s
e
t
A
d
d
re
s
s
(S
ta
rt
B
o
o
t
L
o
a
d
e
r
S
e
c
ti
o
n
)
1
1
512
words
4
0x0000 –
0xFDFF
0xFE00 –
0xFFFF
0xFDFF
0xFE00
1
0
1024
words
8
0x0000 –
0xFBFF
0xFC00 –
0xFFFF
0xFBFF
0xFC00
0
1
2048
words
16
0x0000 –
0xF7FF
0xF800 –
0xFFFF
0xF7FF
0xF800
0
0
4096
words
32
0x0000 –
0xEFFF
0xF000 –
0xFFFF
0xEFFF
0xF000
Note:
1. The different BOOTSZ Fuse configurations are shown in