************************************************ 
*
* Binary to decimal conversion

* OTHER MODULES NEEDED: DECTAB$

* ENTRY: X=buffer for ascii string
*        D=binary value to convert

* EXIT: all registers (except cc) preserved

* BGP - 04/11/2009 - Fixed issue where BIN_DEC was printing negative
* sign in certain cases.  Cleared nega flag to fix issue.

 nam Binary to Decimal Conversion
 ttl Assembler Library Module


 section .bss
nega rmb 1
 endsect

 section .text
BIN_SDEC:
 clr nega,u
 tsta
 bpl  BIN_DEC
 sta nega,u
 comb
 coma
 addd #$0001
 bra BIN_DEC_COMMON	+++ added BGP

BIN_DEC:
 clr nega,u		+++ added BGP
BIN_DEC_COMMON
 pshs a,b,x,y
 lda #7 clear out 7 bytes in buffer

bindc1
 clr ,x+
 deca
 bne bindc1
 ldx 2,s restore buffer start address
 ldd ,s get data
 bne bindc2 not 0, do convert
 lda #'0
 sta ,x
 bra bindc8 exit

bindc2
 tst nega,u
 beq bindc25
 pshs a
 lda #'-
 sta ,x+
 puls a
bindc25
 leay DECTAB$,pcr point to conversion table
 clr ,--s temps, flag 1st dgt not placed

bindc3
 clr 1,s current digit=0

bindc4
 subd ,y sub table element
 bcs bindc5 too far, correct
 inc 1,s bump digit
 bra bindc4 loop til done

bindc5
 addd ,y restore, 1 too many subtracts
 pshs a,b save rest of number
 lda 3,s get the digit
 adda #$30 make it ascii
 cmpa #'0 is it zero?
 bne bindc6 no, skip
 tst 2,s is it 1st digit in string?
 beq bindc7 yes, don't do leading 0s

bindc6
 inc 2,s indidicate at least 1 digit
 sta ,x+ save in buffer

bindc7
 leay 2,y next table entry
 tst 1,y end of table
 puls a,b restore data
 bne bindc3 no..loop
 leas 2,s

bindc8
 puls a,b,x,y,pc restore and return

 endsect