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Rainbow Electronics ATmega3290P_V User Manual

Page 279

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279

ATmega329/3290/649/6490

2552H–AVR–11/06

sbiw loophi:looplo, 1

;use subi for PAGESIZEB<=256

brne Rdloop

; return to RWW section

; verify that RWW section is safe to read

Return:

in

temp1, SPMCSR

sbrs temp1, RWWSB

; If RWWSB is set, the RWW section is not

ready yet

ret

; re-enable the RWW section

ldi

spmcrval, (1<

call Do_spm

rjmp Return

Do_spm:

; check for previous SPM complete

Wait_spm:

in

temp1, SPMCSR

sbrc temp1, SPMEN

rjmp Wait_spm

; input: spmcrval determines SPM action

; disable interrupts if enabled, store status

in

temp2, SREG

cli

; check that no EEPROM write access is present

Wait_ee:

sbic EECR, EEWE

rjmp Wait_ee

; SPM timed sequence

out

SPMCSR, spmcrval

spm

; restore SREG (to enable interrupts if originally enabled)

out

SREG, temp2

ret