From: Scott Dattalo
;****************************************** ;bcd_subtract ; ; Computes z = x  y ; where x,y,z are all 8bit packed BCD numbers ; Exits with C=1 (and DC=1 too) if x>=y ; and with z=1 if x==y. ; Note that z can be aliased to x or y so that ;it's possible to calculate x = xy or y = xy ; 9 cycles (+ return) bcd_subtract MOVF y, W ;W = y SUBWF x, W ;W = xy RLF z, F ;lsb of z has the carry SKPDC ;if lsn of x < lsn of y ADDLW 0x06 ; then convert lsn of the ; result to BCD. BTFSS z, 0 ;Similarly for the msn's ADDLW 0x60 RRF z, F ;Get the carry MOVWF z ;and save the result RETURN
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file: /Techref/microchip/math/sub/bcdp2.htm, 1KB, , updated: 2000/2/11 14:56, local time: 2020/1/18 04:36,

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