Motorola DSP56000, 24-Bit Digital Signal Processor Figure B-1 20-Tap FIR Filter Example Sheet 1

BENCHMARK PROGRAMS

page 132,66,0,6
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;********************************************************
;Motorola Austin DSP Operation			June 30, 1988
;********************************************************
;DSP56000/1
;20 - tap FIR filter
;File name: 1-56.asm
;*********************************************************************************************************************
; Maximum sample rate: 379.6 kHz at 20.5 MHz/500.0 kHz at 27.0 MHz
; Memory Size: Prog: 4+6 words; Data: 2x20 words
; Number of clock cycles: 54 (27 instruction cycles)
; Clock Frequency: 20.5 MHz/27.0 MHz
; Instruction cycle time: 97.6 ns/74.1 ns
;*********************************************************************************************************************
; This FIR filter reads the input sample
; from the memory location Y:input
; and writes the filtered output sample
; to the memory location Y:output
;
; The samples are stored in the X memory
; The coefficients are stored in the Y memory
;**********************************************************************************************************************
;		X MEMORY		Y MEMORY
;
;		R0	X(n)	c(0)
;		t
;			X(n-1)	t,t+T
				c(1)
;
;
;
;
;			X(n-k+1) X(n+1)	c(k-1)
;		t+T
;
;			C(0)
;	x(n)			y(n)
;
			X	+
;
				k – 1
;
;			T	y(n) = ∑ c( p) ⋅ (n – p)
;				p = 0
;			C(1)
;
;			X
;
;
;			T
;
			C(2)
;
;			X
;
;
;
;			T
;
			C(K-1)
;
;			X
;
;			FIR
;
	Figure B-1 20-Tap FIR Filter Example (Sheet 1 of 2)
;
;

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