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Updated rules.mak for all the os9 format's to format the entire disk. People were having some issues with the disk images not being formatted to their full capacity and preventing some functions from working.
author drencor-xeen
date Thu, 17 Jan 2013 11:03:26 -0600
parents 7d70b7e1cb21
children aaba193af04f
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************************************

* 16 x 16 Multiply

* ENTRY: D = multiplier
*        X = multiplicand

*  EXIT: Y = product 2 msbs
*        U =    "    2 lsbs
*        D & X preserved

 nam 16x16 bit Multiply
 ttl Assembler Library Module


 psect MULT16,0,0,0,0,0

MULT16:
 PSHS D,X,Y,U save #s and make stack room
 CLR 4,S reset overflow flag
 LDA 3,S get byte
 MUL
 STD 6,S save B x Xl
 LDD 1,S
 MUL B x Xh
 ADDB 6,S
 ADCA #0
 STD 5,S add 1st 2 mult.
 LDB 0,S
 LDA 3,S
 MUL A x Xl
 ADDD 5,S
 STD 5,S add result to previous
 BCC no.ov branch if no overflow
 INC 4,S set overflow flag

no.ov
 LDA 0,S
 LDB 2,S
 MUL A x Xh
 ADDD 4,S
 STD 4,S
 PULS D,X,Y,U,PC return

 endsect