view lib/alib/mult16x8.a @ 2668:07441dfebc27 lwtools-port

Make tocgen build with lwasm lwasm does not treat a trailing colon as part of the symbol name. Removed trailing colons on symbol references.
author William Astle <lost@l-w.ca>
date Sun, 10 Jun 2012 13:35:44 -0600
parents 7d70b7e1cb21
children aaba193af04f
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***********************************

* 16 x 8 Multiply (24 bit result)

* OTHER MODULES NEEDED: none

* ENTRY: A = multiplier
*        X = multiplicand

*  EXIT: A = product byte 1
*        X = product bytes 2 & 3

 nam 16x8 bit Multiply
 ttl Assembler Library Module


 psect MULT168,0,0,0,0,0
 
MULT168:
 PSHS A,X save numbers
 LEAS -3,S room for product
 LDB 5,S get lsb of multiplicand
 MUL
 STD 1,S save partial product
 LDD 3,S get mupltiplier & msb of multp.
 MUL
 ADDB 1,S add lsb to msb
 ADCA #0 add carry
 STD 0,S save sum of partial products
 LDX 1,S get 2 lsb's
 LEAS 6,S clean stack
 RTS

 endsect