ATMEGA48V_11 ATMEL [ATMEL Corporation], ATMEGA48V_11 Datasheet - Page 280

• Manufacturer Part Number: ATMEGA48V_11
• Description: 8-bit Atmel Microcontroller with 4/8/16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

2545T–AVR–05/11
Rdloop:
Return:
Do_spm:
Wait_spm:
Wait_ee:
ldi
call Do_spm
; read back and check, optional
ldi
ldi
subi YL, low(PAGESIZEB)
sbci YH, high(PAGESIZEB)
lpm
ld
cpse r0, r1
jmp
sbiw loophi:looplo, 1
brne Rdloop
; return to RWW section
; verify that RWW section is safe to read
in
sbrs temp1, RWWSB
ret
; re-enable the RWW section
ldi
call Do_spm
rjmp Return
; check for previous SPM complete
in
sbrc temp1, SELFPRGEN
rjmp Wait_spm
; input: spmcrval determines SPM action
; disable interrupts if enabled, store status
in
cli
; check that no EEPROM write access is present
sbic EECR, EEPE
rjmp Wait_ee
; SPM timed sequence
out
spm
; restore SREG (to enable interrupts if originally enabled)
out
ret
spmcrval, (1<<RWWSRE) | (1<<SELFPRGEN)
looplo, low(PAGESIZEB)
loophi, high(PAGESIZEB)
r0, Z+
r1, Y+
Error
temp1, SPMCSR
spmcrval, (1<<RWWSRE) | (1<<SELFPRGEN)
temp1, SPMCSR
temp2, SREG
SPMCSR, spmcrval
SREG, temp2
; If RWWSB is set, the RWW section is not ready yet
;init loop variable
;not required for PAGESIZEB<=256
;restore pointer
;use subi for PAGESIZEB<=256
ATmega48/88/168
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