test5.s

THIS DESIGNE PROGRAM.

N			EQU		100

;-------------------------

			AREA	Example5,CODE,READONLY
			ENTRY
			CODE32
		
;-------------------------

ARM_CODE	LDR		SP,=0x40003f00
			ADR		R0,THUMB_CODE+1
			BX		R0
			
;--------------------------

			LTORG
			
			CODE16

;---------------------------

THUMB_CODE	LDR		R0,=N
			BL		SUM_N
			
			B		THUMB_CODE
			
;---------------------------

SUM_N		PUSH	{R1-R7,LR}
			MOVS	R2,R0
			BEQ		SUM_END
			
			;----------------
			CMP		R2,#1
			BEQ		SUM_END
			
			;----------------
			MOV		R1,#1
			MOV		R0,#0
SUM_L1		ADD		R0,R1
			BCS		SUM_ERR
			CMP		R1,R2
			BHS		SUM_END
			ADD		R1,#1
			B		SUM_L1


			;-------------
SUM_ERR		MOV		R0,#0			
				
		
			
SUM_END		POP		{R1-R7,PC}			
			
			
;----------------------------			
			END