BENCHMARK PROGRAMS
B - 6 BENCHMARK PROGRAMS MOTOROLA
page 132,66,0,6
opt rc
;********************************************************
;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
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R0 X(n)
X(n-1)
t
t+T X(n-k+1) X(n+1)
t,t+T c(0)
c(1)
c(k-1)
C(0)
X
x(n)
X
C(1)
X
C(2)
X
C(K-1)
FIR
T
T
T
yn() cp() np–()×
p0=
k1–
∑
=
+y(n)
Figure B-1 20-Tap FIR Filter Example (Sheet 1 of 2)