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;routine for bcd to binary conversion in assembly
;answer in R0(Lower byte),R1(middle byte),R2(Higherbyte)

.equ unit,030h
.equ ten,031h
.equ hund,032h
.equ thous,033h
.equ tenthous,034h
.equ lacs,035h
.equ tmp_carry,039h
.equ addingreg,03ah

.org 0000
ljmp main


.org 0070h
main: mov SP,#060h

mov unit,#06h ;as for example
mov ten,#01h
mov hund,#04h
mov thous,#08h
mov tenthous,#02h
mov lacs,#09h

mov R0,lacs
mov R1,#0
mov R2,#0

lcall mulroutine

mov addingreg,tenthous

lcall sumroutine

lcall mulroutine

mov addingreg,thous

lcall sumroutine

lcall mulroutine

mov addingreg,hund

lcall sumroutine

lcall mulroutine

mov addingreg,ten

lcall sumroutine

lcall mulroutine

mov addingreg,unit

lcall sumroutine

main1: sjmp main1





mulroutine: mov a,R0
mov b,#0ah
mul ab

mov tmp_carry,b
mov R0,a

mov a,R1
mov b,#0ah
mul ab

clr c
add a,tmp_carry
mov R1,a

mov a,b
addc a,#00h
mov tmp_carry,a

mov a,R2
mov b,#0ah
mul ab

add a,tmp_carry
mov R2,a

ret



sumroutine:
clr c
mov a,R0
addc a,addingreg
mov R0,a

mov a,R1
addc a,#0h
mov R1,a

mov a,R2
addc a,#0h
mov R2,a

ret