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Loopcounter in bit_reverse opcode eingefügt

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Jörg Thalheim 2015-03-05 16:24:22 +01:00
parent a0939290bb
commit 5b5ee5fdf0
2 changed files with 18 additions and 14 deletions
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12
fft.c
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@ -61,13 +61,14 @@ int fix_fft(fixed fr[], fixed fi[], int m, int inverse)
scale = 0; scale = 0;
int mm = m; int mm = m;
xtbool t;
/* decimation in time - re-order data */ /* decimation in time - re-order data */
for(m=1; m<=nn; ++m) { for(m=0;;) {
mr = FFT_bit_reverse(m, mm); FFT_bit_reverse(m, mr, mm);
if(m >= nn) break;
if(mr <= m) continue; if(mr <= m) continue;
tr = fr[m]; tr = fr[m];
fr[m] = fr[mr]; fr[m] = fr[mr];
fr[mr] = tr; fr[mr] = tr;
@ -97,10 +98,10 @@ int fix_fft(fixed fr[], fixed fi[], int m, int inverse)
if(FFT_shift_check(j,m)) if(FFT_shift_check(j,m))
{ {
shift = 1; shift = 1;
++scale;
break; break;
} }
} }
if(shift) ++scale;
} }
else else
{ {
@ -128,6 +129,7 @@ int fix_fft(fixed fr[], fixed fi[], int m, int inverse)
{ {
i = RUR_FFT_loop(); i = RUR_FFT_loop();
xtbool t;
FFT_loop_check(n, istep, t, j); FFT_loop_check(n, istep, t, j);
if(!t) if(!t)
break; break;

20
fft_inst.tie
View File

@ -150,17 +150,19 @@ operation FFT_loop_check {in AR n, in AR istep, out BR t, out AR j} {inout FFT_l
assign j = TIEadd(FFT_loop, {1'b0, istep[15:1]}, 1'b0); assign j = TIEadd(FFT_loop, {1'b0, istep[15:1]}, 1'b0);
} }
operation FFT_bit_reverse {in AR b, out AR o, in AR m} {} operation FFT_bit_reverse {inout AR m, out AR mr, in AR mm} {}
{ {
assign o = { wire [15:0] x = TIEadd(m, 0, 1'b1);
TIEmux(m[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, b[0]), assign mr = {
TIEmux(m[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, b[0], b[1]), TIEmux(mm[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, x[0]),
TIEmux(m[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, b[0], b[1], b[2]), TIEmux(mm[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, x[0], x[1]),
TIEmux(m[2:0], 1'b0, 1'b0, 1'b0, 1'b0, b[0], b[1], b[2], b[3]), TIEmux(mm[2:0], 1'b0, 1'b0, 1'b0, 1'b0, 1'b0, x[0], x[1], x[2]),
TIEmux(m[2:0], 1'b0, 1'b0, 1'b0, b[0], b[1], b[2], b[3], b[4]), TIEmux(mm[2:0], 1'b0, 1'b0, 1'b0, 1'b0, x[0], x[1], x[2], x[3]),
TIEmux(m[2:0], 1'b0, 1'b0, b[0], b[1], b[2], b[3], b[4], b[5]), TIEmux(mm[2:0], 1'b0, 1'b0, 1'b0, x[0], x[1], x[2], x[3], x[4]),
TIEmux(m[2:0], 1'b0, b[0], b[1], b[2], b[3], b[4], b[5], b[6]) TIEmux(mm[2:0], 1'b0, 1'b0, x[0], x[1], x[2], x[3], x[4], x[5]),
TIEmux(mm[2:0], 1'b0, x[0], x[1], x[2], x[3], x[4], x[5], x[6])
}; };
assign m = x;
} }
operation FFT_twiddle {out AR wr, out AR wi, in AR j, in BR shift, in BR inverse} {} operation FFT_twiddle {out AR wr, out AR wi, in AR j, in BR shift, in BR inverse} {}