Can you provide comment annotations on this code explaining what every line is d

Question

Can you provide comment annotations on this code explaining what every line is doing

LEDS_ON:

SER R16 ;set r16 to 0xff

  OUT DDRA, R16 ;set all porta pins to output state

  OUT PORTA, R16 ;set all pins as logic high

  OUT PORTA, R16

  RET

LEDS_OFF:

SER R16 ;set r16 to 0xff

  OUT DDRA, R16 ;set all porta pins to output state

  CLR R16 ;set all pins as logic high

  OUT PORTA, R16

  RET

DELAY500:

LDI R18, 50

L3: LDI R16, 255

BACK: LDI R17, 255

HERE:

DEC R17

BRNE HERE

BRNE BACK

DEC R16

BRNE BACK

DEC R18

BRNE L3

RET

Explanation / Answer

LEDS_ON:

LEDS_OFF:

SER R16 ; set all bits in register R16,

OUT DDRA, R16 ; Configure PORTA as an Output port

CLR R16 ; clear value of R16 register

OUT PORTA, R16; Write PORTA

RET; Return to main loop

DELAY500: Delay of 500ms; stop the program for a half-second.

LDI R18, 50; load register R17 with 50

L3: LDI R16, 255; In L3 length register of 32bit, load register R16 with 255

BACK: LDI R17, 255; Write Back the register R17 with 255

HERE:

DEC R17; Decrement register R17

BRNE HERE; Branch if not equal, loop HERE

BRNE BACK; Branch if not equal, loop BACK

DEC R16; Decrement register R17

BRNE BACK; Branch if not equal, loop BACK

DEC R18; Decrement register R18

BRNE L3; Branch if not equal, loop register L3

RET; Return to main loop

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