MULS:
MOV R4,#0
MOV R5,#0
LCALL MDS
MDS:
CLR F0
MOV A,R6
JNB ACC.7,MDS1
CPL F0
XCH A,R7
CPL A
ADD A,#1
XCH A,R7
CPL A
ADDC A,#0
MOV R6,A
MULD:
MOV A,R3
MOV B,R7
MUL AB
MOV R4,B
MOV R5,A
MOV A,R3
MOV B,R6
MUL AB
ADD A,R4
MOV R4,A
CLR A
ADDC A,B
MOV R3,A
MOV A,R2
MOV B,R7
MUL AB
ADD A,R4
MOV R4,A
MOV A,R3
ADDC A,B
MOV R3,A
CLR A
RLC A
XCH A,R2
MOV B,R6
MUL AB
ADD A,R3
MOV R3,A
MOV A,R2
ADDC A,B
MOV R2,A
JB F0,MDS2
MDS2:
MOV A,R5
CPL A
ADD A,#1
MOV R5,A
MOV A,R4
CPL A
ADDC A,#0
MOV R4,A
MOV A,R3
CPL A
ADDC A,#0
MOV R3,A
MOV A,R2
CPL A
ADDC A,#0
MOV R2,A
CLR OV
RET