Add ES/Lab/LAB5/FACTORIAL.asm

ES/Lab/LAB5/FACTORIAL.asm

@@ -0,0 +1,37 @@
+	AREA RESET, DATA, READONLY
+	EXPORT __Vectors
+__Vectors
+	DCD 0x10001000
+	DCD Reset_Handler
+	ALIGN
+	
+	AREA MYCODE, CODE, READONLY
+	ENTRY
+	EXPORT Reset_Handler
+
+Reset_Handler
+	LDR R1, =5
+	BL fact
+	LDR R12, =0x10001000
+	STR R0, [R12] 
+	
+STOP
+	B STOP
+
+fact
+	CMP R1, #1
+	BLE base_case
+	
+	PUSH{R1, LR}
+	SUB R1, R1, #1
+	BL fact
+	
+	POP{R2, LR}
+	MUL R0, R0, R2
+	BX LR
+
+base_case
+	MOV R0, #1
+	BX LR
+
+	END