CSC103 2011 Assembly Language Examples

--D. Thiebaut 11:37, 15 February 2011 (EST)

---

Program 1

A program that computes the sum of all the integers between 1 and 5 and stores it into a variable called sum.

start:	lod	counter
		add sum
		sto sum
		lod counter
		sub-c 1
		sto counter
		jmz	done
		jmp	start
done:	hlt


counter:	5
sum:		0

Program 2

; program to display a bit pattern in graphics memory
start:		lod 	pattern			;get the pattern
			sto-i	index				;store it in the image, at a location
			lod		index				;get the image index
			add-c	1					;make it point to next word in mem
			sto		index				;store it back
			lod		count				;get the counter
			sub-c	1					;subtract one
			sto		count				;store back
			jmz		done				;if counter is 0, we're done
			lod		pattern			;if not, we check the pattern
			add		pattern			;shift it to the left by 1 bit
			sto		pattern			;store it back
			jmz		resetPattern		;if pattern is 0, reset it
			jmp		start				;loop back
resetPattern:							;reset pattern to 1
			lod-c	1
			sto		pattern
			jmp		start
done:		hlt							;we're done!

pattern:	1							;the pattern to store in graphics mem
count:		1000						;how many words we fill up
index:		image						;pointer to the image words
image:		data						;the image starts here

Program #3

• Add 4 numbers together. No loops.

start:	lod		data1
		add		data2
		add		data3
		add		data4
		sto		sum
		hlt


	@14
data1:	1
data2: 2
data3: 3
data4:	4
sum:	data

Program 4

• Add all the numbers between 1 and 10 in a loop

start:	lod		count
		add		sum
		sto 	sum
		lod		count
		sub-c	1
		sto		count
		jmz		done
		jmp		start
done:	hlt


		@14
count:	10
sum:	data