Motorola DSP96002 - Manual (Page 700)

MOTOROLA DSP96002 USER’S MANUAL B-181
depftst d7,d0,d1 ;
jset #5,sr,_snan2 ;
jmp _done ;
_snan2 jset #13,sr,_op2sn ;
jmp _done ;
_op2sn ftfr.x d7,d6 ;
_op1sn bset #30,d6.m ;
ftfr.x d6,d5 ;
bset #4,sr ;
bset #13,sr ;
bset #20,sr ;
_done nop ;
nop
nop
rts ; end of subroutine
endsec
B.5 NON-IEEE DOUBLE PRECISION USING SOFTWARE EMULATION
dplib ident 1,0
;
; MOTOROLA DSP96002 DPLIB - VERSION 1.0
;
; EXTENDED DOUBLE PRECISION floating-point SUBROUTINE LIBRARY
;
page 132,60,1,1
;
; equates
;
exp equ 0 ;offset to exponent
sign equ 1 ;offset to sign
ms equ 2 ;offset to most significant word
ls equ 3 ;offset to least significand word
bias equ $1fffffff ;exponent bias
dptemp equ $1fc ;temporary storage in top 4 internal
;x memory locations
page
org x:dptemp ;double precision register
ds 1 ;exponent
ds 1 ;sign: 0=+, 1=-
ds 2 ;64 bit significand
;
page
org p:
;
; MOTOROLA DSP96002 DPLIB - VERSION 1.0
;
; IEEE2DPLIB - Convert floating-point number in d0 to an internal