To execute page write, set up the address
in the Z-pointer, write “X0000101” to SPMCR and execute SPM within four clock cycles
after writing SPMCR. The data in R1 and R0 is ignored. The page address must be written
to PCPAGE. Other bits in the Z-pointer must be written to zero during this
operation.
- Page Write to the RWW section: The
NRWW section can be read during the Page Write
- Page Write to the NRWW section: The
CPU is halted during the operation
Note: If an interrupt occurs in the timed
sequence the four cycle access cannot be guaranteed. In order to ensure atomic operation
disable interrupts before writing to SPMCR.