
499
42073A-MCU Wireless-02/13
ATmega2564/1284/644RFR2
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2048
words
16
0x00000 –
0x1F7FF
0x1F800 –
0x1FFFF
0x1F7FF
0x1F800
0
4096
words
32
0x00000 –
0x1EFFF
0x1F000 –
0x1FFFF
0x1EFFF
0x1F000
Note:
30.7 Register Description
30.7.1 SPMCSR – Store Program Memory Control Register
Bit
7
6
5
4
3
2
1
0
$37 ($57)
SPMIE
RWWSB
SIGRD
RWWSRE BLBSET PGWRT
PGERS
SPMEN
SPMCSR
Read/Write
RW
R
RW
Initial Value
0
The Store Program Memory Control Register contains the control bits needed to control
the Boot Loader operations. Note: Only one SPM instruction should be active at any
time.
Bit 7 – SPMIE - SPM Interrupt Enable
When the SPMIE bit is written to one, and the I-bit in the Status Register is set (one),
the SPM ready interrupt will be enabled. The SPM ready Interrupt will be executed as
long as the SPMEN bit in the SPMCR register is cleared.
Bit 6 – RWWSB - Read While Write Section Busy
When a self-programming (page erase or page write) operation to the RWW section is
initiated, the RWWSB will be set (one) by hardware. When the RWWSB bit is set, the
RWW section cannot be accessed. The RWWSB bit will be cleared if the RWWSRE bit
is written to one after a self-programming operation is completed. Alternatively the
RWWSB bit will automatically be cleared if a page load operation is initiated.
Bit 5 – SIGRD - Signature Row Read
If this bit is written to one at the same time as SPMEN, the next LPM instruction within
three clock cycles will read a byte from the signature row into the destination register. A
SPM instruction within four cycles after SIGRD and SPMEN are set, will have no effect.
This operation is reserved for future use and should not be used.
Bit 4 – RWWSRE - Read While Write Section Read Enable
When programming (page erase or page write) to the RWW section, the RWW section
is blocked for reading (the RWWSB will be set by hardware). To re-enable the RWW
section, the user software must wait until the programming is completed (SPMEN will
be cleared). Then, if the RWWSRE bit is written to one at the same time as SPMEN,
the next SPM instruction within four clock cycles re-enables the RWW section. The
RWW section cannot be re-enabled while the Flash is busy with a page erase or a page