-
Notifications
You must be signed in to change notification settings - Fork 0
/
fft.spin
548 lines (481 loc) · 23.5 KB
/
fft.spin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
''*******************************************************
''* FFT and Spectrogram Prototype v1.0 *
''* http://propeller.wikispaces.com/FFT *
''* http://forums.parallax.com/showthread.php?p=803389 *
''* *
''* Converted to Propeller Assembler by Pacito.Sys, *
''* based on int_fft.c by Tom Roberts *
''* with portability by Malcolm Slaney. *
''* Distributed under the terms of the GNU GPL v2.0. *
''* *
''* Integer FFT *
''* 16 bit signed values are used *
''* *
''* Modified by Pete Hemery - Oct, Nov, Dec 2011 *
''* *
''* See end of file for terms of use. *
''*******************************************************
CON
_clkmode = xtal1+pll16x
_xinfreq = 5_000_000
BITS_NN= 10 ' 2 ^ BITS_NN. 10 = 1024 bits.
BITS_NNM1=BITS_NN-1
NN= |<BITS_NN 'Nifty bitwise decode
BITS_DIFF=3
VAR
' Local object pointer declarations
long flag_ptr
long time_ptr
long real_ptr
long imag_ptr
long scrn_ptr
PUB start(in_flag_ptr,in_time_ptr,in_real_ptr,in_imag_ptr,in_scrn_ptr) : okay
{{
Start - This function populates the local pointers with values passed from the Top Level Object,
then launches the PASM FFT object on a cog and passes the first address of the parameter list.
The PASM object reads the parameter list into cog RAM on launch and then waits for its flag
to change, indicating the input buffer has been filled.
}}
flag_ptr := in_flag_ptr
time_ptr := in_time_ptr
real_ptr := in_real_ptr
imag_ptr := in_imag_ptr
scrn_ptr := in_scrn_ptr
okay := cognew(@init, @flag_ptr) + 1
PUB stop(cog)
{{
This function stops the local FFT engine and releases the cog
}}
if cog
cogstop(cog~ - 1)
DAT
'
' Modified FFT Object. This object can be instantiated multiple times.
' The initialisation copies parameters passed from Hub RAM by the calling object.
' These include the Flag pointer, Time Keeping Pointer, Real and Imaginary Buffer Pointers,
' VGA Pixel Array Pointer and Peak Value Array Pointer.
'
' The calling object should allocate consecutive WORD aligned
' Hub RAM locations for the Real and Imaginary buffers. The size of the buffers should be
' read from the BITS_NN constant defined at the top of this file.
org 0
init mov fft_n,#1
shl fft_n,#BITS_NN '1024 point fft
mov in_ptr,PAR
rdlong asm_flag_ptr,in_ptr 'Flag Pointer
add in_ptr,#4
rdlong asm_time_ptr,in_ptr 'Time Keeping Pointer
add in_ptr,#4
rdlong fft_real_buf_ptr,in_ptr 'Real Buffer Pointer - 2048 bytes
add in_ptr,#4
rdlong fft_imag_buf_ptr,in_ptr 'Imaginary Buffer Pointer - 2048 bytes
add in_ptr,#4
rdlong cnt_bitmap_ptr,in_ptr 'VGA Screen Bitmap Pointer
mov peak_ptr,asm_flag_ptr
add peak_ptr,#4 'Peak Value Array Pointer
flag_wait rdlong temp,asm_flag_ptr wz 'wait until flag changes to 0 before looping
if_nz jmp #flag_wait
mov asm_cnt,cnt
wrlong asm_cnt,asm_time_ptr 'keep track of the time when the flag changed
loop call #decimate
call #lets_rock
call #calc_abs
call #plot
add one,#1
wrlong one,asm_flag_ptr 'ack
mov asm_cnt,cnt
wrlong asm_cnt,asm_time_ptr 'keep track of the time
jmp #flag_wait
'inserted cog stop instead of infinite loop
'cogid cog_id
'cogstop cog_id
'end
'init_end 'jmp #init_end ' end
' bit-reversal, uses the nice rev instruction
decimate mov fft_ii,#1
mov fft_ll,fft_n
ldecimate mov fft_jj,fft_ii
rev fft_jj,#32-BITS_NN ' BITS_NN will be reversed
cmp fft_ii,fft_jj wc
if_nc jmp #ldecimate_5
mov fft_fr_ii,fft_ii
mov fft_fr_jj,fft_jj
shl fft_fr_ii,#1
add fft_fr_ii,fft_real_buf_ptr
rdword fft_tr,fft_fr_ii
shl fft_fr_jj,#1
add fft_fr_jj,fft_real_buf_ptr
rdword fft_result,fft_fr_jj
wrword fft_tr,fft_fr_jj
wrword fft_result,fft_fr_ii
ldecimate_5 add fft_ii,#1
cmp fft_ii,fft_ll wc, wz
if_c_or_z jmp #ldecimate
decimate_ret ret
' Calcs the 1024 point-FFT using 16 bit signed integers, some calculations
' are done with 32 bits
lets_rock mov fft_ll,#1
mov fft_k,#BITS_NNM1
lets_rock_while cmp fft_ll,fft_n wc
if_nc jmp #lets_rock_while_e
mov fft_is,fft_ll
shl fft_is,#1
mov fft_m,#0
lets_rock_for_1 cmp fft_m,fft_ll wc
if_nc jmp #lets_rock_for_1_e
mov fft_jj,fft_m
shl fft_jj,fft_k
call #get_sincos
mov fft_ii,fft_m
lets_rock_for_2 cmp fft_ii,fft_n wc
if_nc jmp #lets_rock_for_2_e
mov fft_jj,fft_ii
add fft_jj,fft_ll
mov fft_fi_jj,fft_jj
shl fft_fi_jj,#1 ' word access
mov fft_fr_jj,fft_fi_jj
add fft_fr_jj,fft_real_buf_ptr
add fft_fi_jj,fft_imag_buf_ptr
rdword fft_result,fft_fr_jj
call #lets_mul_wr
mov fft_tr,fft_result
rdword fft_result,fft_fi_jj
call #lets_mul_wi
subs fft_tr,fft_result ' 32 bit signed value
rdword fft_result,fft_fi_jj
call #lets_mul_wr
mov fft_ti,fft_result
rdword fft_result,fft_fr_jj
call #lets_mul_wi
adds fft_ti,fft_result ' 32 bit signed value
mov fft_fi_ii,fft_ii
shl fft_fi_ii,#1 ' word access
mov fft_fr_ii,fft_fi_ii
add fft_fr_ii,fft_real_buf_ptr
add fft_fi_ii,fft_imag_buf_ptr
rdword fft_qr,fft_fr_ii ' qr = fr[i]
shl fft_qr,#16
sar fft_qr,#1 ' scales to 32 bit signed value
mov fft_result,fft_tr
rdword fft_qi,fft_fi_ii ' qi = fi[i]
shl fft_qi,#16
sar fft_qi,#1 ' scales to 32 bit signed value
adds fft_result,fft_qr ' res = tr + qr
subs fft_qr,fft_tr ' qr = qr - tr
shr fft_result,#16 ' scales down
wrword fft_result,fft_fr_ii ' fr[i] = res = tr + qr
mov fft_result,fft_ti
adds fft_result,fft_qi ' res = ti + qi
shr fft_qr,#16 ' scales down
wrword fft_qr,fft_fr_jj ' fr[j] = qr = qr - tr
subs fft_qi,fft_ti ' qi = qi - ti
shr fft_result,#16 ' scales down
wrword fft_result,fft_fi_ii ' fi[i] = ti + qi
shr fft_qi,#16 ' scales down
add fft_ii,fft_is
wrword fft_qi,fft_fi_jj ' fi[j] = qi = qi - ti
jmp #lets_rock_for_2
lets_rock_for_2_e
add fft_m,#1
jmp #lets_rock_for_1
lets_rock_for_1_e sub fft_k,#1
mov fft_ll,fft_is
jmp #lets_rock_while
lets_rock_while_e
lets_rock_ret ret
lets_mul_wi mov fft_sgn,fft_result
and fft_sgn,cnt_sgn wz
shl fft_result,#16
negnz fft_result,fft_result
shr fft_result,#15
shr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wi wc
rcr fft_result,#1 wc
xor fft_sgn,fft_sgnwi wz
negnz fft_result,fft_result
lets_mul_wi_ret ret
lets_mul_wr mov fft_sgn,fft_result
and fft_sgn,cnt_sgn wz
shl fft_result,#16
negnz fft_result,fft_result
shr fft_result,#15
shr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_wr wc
rcr fft_result,#1 wc
xor fft_sgn,fft_sgnwr wz
negnz fft_result,fft_result
lets_mul_wr_ret ret
' Uses the ROM table to get the sine and cosine of jj
get_sincos mov fft_wr,fft_jj
shl fft_wr,#BITS_DIFF
mov fft_wi,fft_wr
add fft_wr,cnt_sin_90
test fft_wi,cnt_sin_90 wc
test fft_wi,cnt_sin_180 wz
negc fft_wi,fft_wi
or fft_wi,cnt_sin_table
shl fft_wi,#1
rdword fft_wi,fft_wi
if_z mov fft_sgnwi,cnt_sgn ' they are inverted
if_nz mov fft_sgnwi,#0
test fft_wr,cnt_sin_90 wc
test fft_wr,cnt_sin_180 wz
negc fft_wr,fft_wr
or fft_wr,cnt_sin_table
shl fft_wr,#1
rdword fft_wr,fft_wr
if_nz mov fft_sgnwr,cnt_sgn ' they are not inverted
if_z mov fft_sgnwr,#0
shl fft_wr,#14
shl fft_wi,#14
get_sincos_ret ret
lets_mul_qr mov fft_result,fft_qr
shl fft_result,#16
abs fft_result,fft_result
mov fft_qr,fft_result
shr fft_result,#16
shr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1 wc
if_c add fft_result,fft_qr wc
rcr fft_result,#1
lets_mul_qr_ret ret
lets_sqrt_qi mov fft_result,#0
mov fft_m,#0
mov fft_jj,#16
lets_sqrt_qi_l shl fft_qi,#1 wc
rcl fft_m,#1
shl fft_qi,#1 wc
rcl fft_m,#1
shl fft_result,#2
or fft_result,#1
cmpsub fft_m,fft_result wc, wr
shr fft_result,#2
rcl fft_result,#1
djnz fft_jj,#lets_sqrt_qi_l
lets_sqrt_qi_ret ret
calc_abs mov fft_ii,#511
mov fft_fr_ii,fft_real_buf_ptr
mov fft_fi_ii,fft_imag_buf_ptr
calc_abs_5 rdword fft_qr,fft_fr_ii
call #lets_mul_qr
mov fft_qi,fft_result
rdword fft_qr,fft_fi_ii
add fft_fi_ii,#2 ' next word
call #lets_mul_qr
add fft_qi,fft_result
call #lets_sqrt_qi
wrword fft_result,fft_fr_ii
add fft_fr_ii,#2 ' next word
djnz fft_ii,#calc_abs_5
calc_abs_ret ret
' This routine will draw the spectrum in a 1bpp 320x240 bitmap
plot mov fft_ii,#40
mov fft_jj,#0
mov fft_fr_ii,fft_real_buf_ptr
plot_8p mov fft_k,#$80
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
shr fft_k,#1
rdword fft_qr,fft_fr_ii
add fft_fr_ii,#2
call #putpix
add fft_jj,#1
djnz fft_ii,#plot_8p
plot_ret ret
putpix mov fft_qi,#239
max fft_qi,fft_qr
mov fft_qr,#239
sub fft_qr,fft_qi
shl fft_qr,#3
mov fft_qi,fft_qr
shl fft_qr,#2
add fft_qr,fft_qi
add fft_qr,cnt_bitmap_ptr
add fft_qr,fft_jj
rdbyte fft_ll,fft_qr
or fft_ll,fft_k
wrbyte fft_ll,fft_qr
putpix_ret ret
' constants
cnt_sgn long $8000
cnt_sin_90 long $0800
cnt_sin_180 long $1000
cnt_sin_table long $7000
cnt_bitmap_ptr long $4000
cnt_add_ptr long 512
' Variables
fft_ii long 0
fft_is long 0
fft_jj long 0
fft_k long 0
fft_ll long 0
fft_m long 0
fft_n long 0
fft_qr long 0
fft_qi long 0
fft_real_buf_ptr long 0
fft_imag_buf_ptr long 0
fft_tr long 0
fft_ti long 0
fft_wr long 0
fft_wi long 0
fft_fi_ii long 0
fft_fr_ii long 0
fft_fi_jj long 0
fft_fr_jj long 0
fft_result long 0
fft_sgn long 0
fft_sgnwr long 0 ' sign of wr
fft_sgnwi long 0 ' sign of wi
peak_ptr long 0
peak_1 long 0
peak_2 long 0
peak_3 long 0
peak_4 long 0
timer_val long 0
in_ptr long 0
asm_flag_ptr long 0
asm_time_ptr long 0
asm_cnt long 0
asm_window_ptr long 0
cog_id long 0
temp long 0
zero long 0
one long 0
''=======[ License ]==========================================================
{{
Demonstration of 1024 point, in-place non-recursive radix-2 FFT using Propeller Assembler.
Copyright (C) 2009 Malcolm Slaney
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
}}