; convert a null-terminated character string to uppter case

		.ORIG x3000

		LEA R3, LOWERA			; load address of Lower “q” in to R3
		LDW R3, R3, #0			; load “q” into R3
						; get read start address
		LEA R0, RSTART			; load address of instruction rstart
		LDW R0, R0, #0			; load x4000
		STB R3, R0, #0			; write “q” to mem[x4000]		

						; get write start address
		LEA R1, WSTART			; load address of instruction wstart
		LDW R1, R1, #0			; load x4002

						; converstion start
LOOP	LDB R2, R0, #0			; load character
		BRz EXIT				; if character is null, exit
		ADD R2, R2, #-16
		ADD R2, R2, #-16		; r2 - 32
WRITE	STB R2, R1, #0			; write r2 to address r1
		ADD R0, R0, #1			; move to next read address
		ADD R1, R1, #1			; move to next write address
		BR LOOP

EXIT	STB	R2, R1, #0			; store null-terminated character
		HALT

RSTART	.FILL x4000
WSTART	.FILL x4002
LOWERA  .FILL x0071        			;This is “q” in ASCii, hexadecimal

		.END