Motorola DSP96002 User Manual page 600

cmp d4,d2
dec d6
jsr _draw_point
_line_y_xn
rts
; Increment x case
; If dx is negative, switch endpoints and sign of dx and dy
_inc_x
tst
jeq
tfr
tfr
neg
neg
tst
jlt
; Increment x, dy positive case
; Set up registers
_set_x_yp
lsr
dec
move
move
move
move
; Draw first point
jsr _draw_point
; Draw additional points
do d4.l,_line_x_yp
inc d6
add d5,d2
cmp d4,d2
inc d7
jsr _draw_point
_line_x_yp
rts
; Increment x, dy negative case
; Set up registers
_set_x_yn
MOTOROLA
ifge
d0
_draw1
d4,d6 iflt
d5,d7 iflt
d0 iflt
d1 iflt
d1
_set_x_yn
d0 d0.l,d2.l
d2 d2.l,d4.l
d0.l,r0
d2.l,m0
d1.l,n0
d1.l,d5.l
r0,d2.l
(r0)+n0
ifge
DSP96002 USER'S MANUAL B-81