Question $2$: $[10$ points$]$

a$)$ The program given below has several errors and it consumes extra memory due to some instructions in the program. Rewrite the program to remove the errors and make it efficient so that it consumes less memory.

$[5$ points$]$

$\backslash$table$[[$LDI R$15,10$ ; initialize loop counter,$],[$LDI $0,$R$17$ ; clear R$17,],[$BACK: LDS R$18,$ $$100,],[$ADD R$17,$R$18,],[$LDS R$19,$ $$30,],[$SUB R$19,$R$17,],[$STS $$32,$R$19,],[$LDI R$20,1,],[$SUB R$15,$R$20,],[$BREQ DONE,$],[$JMP BACK,$],[$DONE: JMP DONE,$]]$

Hint: To reduce memory consumption, recall the memory map of the data address space

b$)$ Write an assembly program to generate two square waves simultaneously $-$ one on each pin PB$3$ and PB$7,$ respectively, as indicated below. Subroutine called DELAY is available for use. Don't use timers here. $[5$ points$]$

$\backslash$table$[[$Square wave of $20\%$ duty cycle on PB$3,$