Texas Instruments TMS320C28x, Reference Manual

Page: 178 / 695

ABSTC ACC
6-21
Example
; Calculate signed: Quot16 = Num16/Den16, Rem16 = Num16%Den16
CLRC TC ; Clear TC flag, used as sign flag
MOV ACC,@Den16 << 16 ; AH = Den16, AL = 0
ABSTC ACC ; Take abs value, TC = sign ^ TC
MOV T,@AH ; Temp save Den16 in T register
MOV ACC,@Num16 << 16 ; AH = Num16, AL = 0
ABSTC ACC ; Take abs value, TC = sign ^ TC
MOVU ACC,@AH ; AH = 0, AL = Num16
RPT #15 ; Repeat operation 16 times
||SUBCU ACC,@T ; Conditional subtract with Den16
MOV @Rem16,AH ; Store remainder in Rem16
MOV ACC,@AL << 16 ; AH = Quot16, AL = 0
NEGTC ACC ; Negate if TC = 1
MOV @Quot16,AH ; Store quotient in Quot16