; Output a calibration tone using table lookup and interpolation.
; 
; written by Quinn Jensen (jensenq@npd.novell.com)
; ref: _Digital Sine-Wave Synthesis Using the DSP56001_,
;	Motorola app note APR1/D rev 1
;

include 'tdsg.basic.a56'

;***************************************************************
;
;	sample rate computations
;
;***************************************************************

dot
	org	x:$20

include	'caltone.inc'

dphase	dc	dphase_h
	org	y:$20
	dc	dphase_l
	org	x:$21
phase	dc	0
sinetab	equ	$100

	org	p:dot
;
; non-interrupt code
;

hf_init
	ori	#4,omr
	rts

eff1_on
eff1_off
eff2_on
eff2_off
eff3_on
eff3_off
eff4_on
eff4_off
	rts

;
; fs = 32.552083 kHz
;

hf_comp
	jsr	<saveregs

#if 0
	move		x:<in_l,a
	move		a,x:<out_l
	move		x:<in_r,a
	move		a,x:<out_r
#endif

	move		l:<phase,a
	move		l:<dphase,y
	move		y0,b
	lsr	b
	move		b1,x1		;x1 = frac
	add	y,a
	move		#>$0000FF,y1
	and	y1,a
	move		a,l:<phase
	move		a1,n0
	move		#sinetab,r0
	movec		#$FF,m0
	nop

	move		y:(r0+n0),y0
	move		y0,a
#if 0
	macr	-x1,y0,a
	move		(r0)+
	move		y:(r0+n0),y0
	macr	y0,x1,a
#endif

	move		a,y0
	move		#ampl,y1
	mpyr	y0,y1,a

	move		a,x:<out_l
	move		a,x:<out_r

bypass
	jsr	<restregs
	rts

	end