; ; Christian Groessler, June 2000 ; ; mul40 ; multiplies A by 40 and returns result in AX ; uses tmp4 .importzp tmp4 .export mul40,loc_tmp .proc mul40 ldx #0 stx tmp4 sta loc_tmp asl a rol tmp4 asl a rol tmp4 ; val * 4 adc loc_tmp bcc L1 inc tmp4 ; val * 5 L1: asl a rol tmp4 ; val * 10 asl a rol tmp4 asl a rol tmp4 ; val * 40 ldx tmp4 rts .endproc .bss loc_tmp:.res 1