VELMA sample problem solution

1a. It computes X² - Y² and puts the result in W, unless one of the squaring operations overflows, in which case it puts the value 0 in W.

1b.

address contents

100 14200114 MOV 114, R2

101 04200002 MUL R2, R2

102 70600111 BVS 111

103 14400115 MOV 115, R4

104 04400004 MUL R4, R4

105 70600111 BVS 111

106 02200004 SUB R4, R2

107 15200116 MOV R2, 116

110 77000000 HALT

111 30000000 CLR R0

112 15000116 MOV R0, 116

113 77000000 HALT

114 00000022 .WORD 22

115 00000033 .WORD 33

116 00000000 .WORD 0

address	contents
100	14200114	MOV 114, R2
101	04200002	MUL R2, R2
102	70600111	BVS 111
103	14400115	MOV 115, R4
104	04400004	MUL R4, R4
105	70600111	BVS 111
106	02200004	SUB R4, R2
107	15200116	MOV R2, 116
110	77000000	HALT
111	30000000	CLR R0
112	15000116	MOV R0, 116
113	77000000	HALT
114	00000022	.WORD 22
115	00000033	.WORD 33
116	00000000	.WORD 0

[on to problem #5]