FMUL: MOV A,R3 ORL A,R4 JZ MUL6 MOV A,R6 ORL A,R7 JZ MUL5 MOV A,R7 MOV B,R4 MUL AB MOV A,B XCH A,R7 MOV B,R3 MUL AB ADD A,R7 MOV R7,A CLR A ADDC A,B XCH A,R4 MOV B,R6 MUL AB ADD A,R7 MOV R7,A MOV A,B ADDC A,R4 MOV R4,A CLR A RLC A XCH A,R3 MOV B,R6 MUL AB ADD A,R4 MOV R4,A MOV A,B ADDC A,R3 MOV R3,A JB ACC.7,MUL2 MOV A,R7 RLC A MOV R7,A LCALL RL1 MUL2: MOV A,R7 JNB ACC.7,MUL3 INC R4 MOV A,R4 JNZ MUL3 INC R3 MOV A,R3 JNZ MUL3 MOV R3,#80H INC R2 MUL3: MOV A,R2 ADD A,R5 MD: MOV R2,A JB ACC.7,MUL4 JNB ACC.6,MUL6 MOV R2,#3FH SETB OV RET MUL4: JB ACC.6,MUL6 MUL5: CLR A MOV R3,A MOV R4,A MOV R2,#41H MUL6: CLR OV RET