ATMEGA64L-8MI View Datasheet(PDF) - Atmel Corporation

Part Name

Description

Manufacturer

ATMEGA64L-8MI

8-bit AVR® Microcontroller with 64K Bytes In-System Programmable Flash

Atmel Corporation 

subi

sbci

ldi

call

ZL, low(PAGESIZEB)

;restore pointer

ZH, high(PAGESIZEB)

;not required for PAGESIZEB<=256

spmcrval, (1<<PGWRT) | (1<<SPMEN)

Do_spm

; re-enable the RWW section

ldi spmcrval, (1<<RWWSRE) | (1<<SPMEN)

call Do_spm

; read back and check, optional

ldi looplo, low(PAGESIZEB) ;init loop variable

ldi loophi, high(PAGESIZEB) ;not required for PAGESIZEB<=256

subi YL, low(PAGESIZEB)

;restore pointer

sbci YH, high(PAGESIZEB)

Rdloop:

lpm r0, Z+

ld r1, Y+

cpse r0, r1

jmp Error

sbiw loophi:looplo, 1

;use subi for PAGESIZEB<=256

brne Rdloop

; return to RWW section

; verify that RWW section is safe to read

Return:

lds 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<<RWWSRE) | (1<<SPMEN)

call Do_spm

rjmp Return

Do_spm:

; check for previous SPM complete

Wait_spm:

lds 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

sts SPMCSR, spmcrval

spm

; restore SREG (to enable interrupts if originally enabled)

out SREG, temp2

ret

288 ATmega64(L)

2490G–AVR–03/04

Share Link: