Working on DSSS demodulator sim

5 files changed, 198 insertions, 15 deletions

diff --git a/controller/fw/tools/cwt_wavelet_header_gen.py b/controller/fw/tools/cwt_wavelet_header_gen.py
new file mode 100644
index 0000000..e9713a7
--- /dev/null
+++ b/controller/fw/tools/cwt_wavelet_header_gen.py
@@ -0,0 +1,29 @@
+#!/usr/bin/env python3
+
+import textwrap
+
+import scipy.signal as sig
+import numpy as np
+
+if __name__ == '__main__':
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument('n', type=int, help='Window size')
+    parser.add_argument('w', type=float, help='Wavelet width')
+    parser.add_argument('-v', '--variable', default='cwt_ricker_table', help='Name for alias variable pointing to generated wavelet LUT')
+    args = parser.parse_args()
+    
+    print(f'/* CWT Ricker wavelet LUT for {args.n} sample window of width {args.w}. */')
+    varname = f'cwt_ricker_{args.n}_window_{str(args.w).replace(".", "F")}'
+    print(f'const float {varname}[{args.n}] = {{')
+
+    win = sig.ricker(args.n, args.w)
+    par = ' '.join(f'{f:>015.8g}f,' for f in win)
+    print(textwrap.fill(par,
+        initial_indent=' '*4, subsequent_indent=' '*4,
+        width=120,
+        replace_whitespace=False, drop_whitespace=False))
+    print('};')
+    print()
+    print(f'const float * const {args.variable} __attribute__((weak)) = {varname};')
+
diff --git a/controller/fw/tools/dsss_demod_test.c b/controller/fw/tools/dsss_demod_test.c
new file mode 100644
index 0000000..51742b1
--- /dev/null
+++ b/controller/fw/tools/dsss_demod_test.c
@@ -0,0 +1,84 @@
+
+#include <stdint.h>
+#include <math.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/fcntl.h>
+
+#include "dsss_demod.h"
+
+void print_usage() {
+    fprintf(stderr, "Usage: dsss_demod_test [test_data.bin]\n");
+}
+
+int main(int argc, char **argv) {
+    if (argc != 2) {
+        fprintf(stderr, "Error: Invalid arguments.\n");
+        print_usage();
+        return 1;
+    }
+
+    int fd = open(argv[1], O_RDONLY);
+    struct stat st;
+    if (fstat(fd, &st)) {
+        fprintf(stderr, "Error querying test data file size: %s\n", strerror(errno));
+        return 2;
+    }
+
+    if (st.st_size < 0 || st.st_size > 1000000) {
+        fprintf(stderr, "Error reading test data: too much test data (size=%zd)\n", st.st_size);
+        return 2;
+    }
+
+    if (st.st_size % sizeof(float) != 0) {
+        fprintf(stderr, "Error reading test data: file size is not divisible by %zd (size=%zd)\n", sizeof(float), st.st_size);
+        return 2;
+    }
+
+    char *buf = malloc(st.st_size);
+    if (!buf) {
+        fprintf(stderr, "Error allocating memory");
+        return 2;
+    }
+
+    fprintf(stderr, "Reading %zd samples test data...", st.st_size/sizeof(float));
+    size_t nread = 0;
+    while (nread < st.st_size) {
+        ssize_t rc = read(fd, buf, st.st_size - nread);
+
+        if (rc == -EINTR || rc == -EAGAIN)
+            continue;
+
+        if (rc < 0) {
+            fprintf(stderr, "\nError reading test data: %s\n", strerror(errno));
+            return 2;
+        }
+        
+        if (rc == 0) {
+            fprintf(stderr, "\nError reading test data: Unexpected end of file\n");
+            return 2;
+        }
+
+        nread += rc;
+    }
+    fprintf(stderr, " done.\n");
+
+    const size_t n_samples = st.st_size / sizeof(float);
+    float *buf_f = (float *)buf;
+
+    fprintf(stderr, "Starting simulation.\n");
+
+    struct dsss_demod_state demod;
+    memset(&demod, 0, sizeof(demod));
+    for (size_t i=0; i<n_samples; i++) {
+        //fprintf(stderr, "Iteration %zd/%zd\n", i, n_samples);
+        dsss_demod_step(&demod, buf_f[i], i);
+    }
+
+    return 0;
+}
diff --git a/controller/fw/tools/dsss_demod_test_runner.py b/controller/fw/tools/dsss_demod_test_runner.py
new file mode 100644
index 0000000..4e93d7b
--- /dev/null
+++ b/controller/fw/tools/dsss_demod_test_runner.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+
+import os
+from os import path
+import subprocess
+import json
+
+import numpy as np
+np.set_printoptions(linewidth=240)
+
+
+if __name__ == '__main__':
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument(metavar='test_data_directory', dest='dir', help='Directory with test data .bin files')
+    default_binary = path.abspath(path.join(path.dirname(__file__), '../build/tools/dsss_demod_test'))
+    parser.add_argument(metavar='test_binary', dest='binary', nargs='?', default=default_binary)
+    parser.add_argument('-d', '--dump', help='Write raw measurements to JSON file')
+    args = parser.parse_args()
+
+    bin_files = [ path.join(args.dir, d) for d in os.listdir(args.dir) if d.lower().endswith('.bin') ]
+
+    savedata = {}
+    for p in bin_files:
+        output = subprocess.check_output([args.binary, p], stderr=subprocess.DEVNULL)
+        measurements = np.array([ float(value) for _offset, value in [ line.split() for line in output.splitlines() ] ])
+        savedata[p] = list(measurements)
+
+        # Cut off first and last sample for mean and RMS calculations as these show boundary effects.
+        measurements = measurements[1:-1]
+        mean = np.mean(measurements)
+        rms = np.sqrt(np.mean(np.square(measurements - mean)))
+
+        print(f'{path.basename(p):<60}:    mean={mean:<8.4f}Hz rms={rms*1000:.3f}mHz')
+
+    if args.dump:
+        with open(args.dump, 'w') as f:
+            json.dump(savedata, f)
+
diff --git a/controller/fw/tools/freq_meas_test.c b/controller/fw/tools/freq_meas_test.c
index df3e39d..e80290e 100644
--- a/controller/fw/tools/freq_meas_test.c
+++ b/controller/fw/tools/freq_meas_test.c
@@ -70,7 +70,7 @@ int main(int argc, char **argv) {
     }
     fprintf(stderr, " done.\n");
 
-    size_t n_samples = st.st_size / sizeof(float);
+    const size_t n_samples = st.st_size / sizeof(float);
     float *buf_f = (float *)buf;
 
     int16_t *sim_adc_buf = calloc(sizeof(int16_t), n_samples);
diff --git a/controller/fw/tools/gold_code_header_gen.py b/controller/fw/tools/gold_code_header_gen.py
index e2bc210..8247457 100644
--- a/controller/fw/tools/gold_code_header_gen.py
+++ b/controller/fw/tools/gold_code_header_gen.py
@@ -1,6 +1,9 @@
 #!/usr/bin/env python3
 
+import sys
+import math
 import textwrap
+import contextlib
 
 import numpy as np
 import scipy.signal as sig
@@ -24,22 +27,50 @@ def gold(n):
     (seq0, _st0), (seq1, _st1) = sig.max_len_seq(n, taps=t0), sig.max_len_seq(n, taps=t1)
     return gen_gold(seq0, seq1)
 
+@contextlib.contextmanager
+def print_include_guards(macro_name):
+    print(f'#ifndef {macro_name}')
+    print(f'#define {macro_name}')
+    yield
+    print(f'#endif /* {macro_name} */')
+
 if __name__ == '__main__':
     import argparse
-    parser = argparse.ArgumentParser()
+    parser = argparse.ArgumentParser(add_help=False)
     parser.add_argument('n', type=int, choices=preferred_pairs, help='bit width of shift register. Generate 2**n + 1 sequences of length 2**n - 1.')
+    parser.add_argument('-v', '--variable', default='gold_code_table', help='Name for weak alias of generated table')
+    parser.add_argument('-h', '--header', action='store_true', help='Generate header file')
+    parser.add_argument('-c', '--source', action='store_true', help='Generate table source file')
     args = parser.parse_args()
 
-    print('#include <unistd.h>')
-    print()
-    print(f'/* {args.n} bit gold sequences: {2**args.n+1} sequences of length {2**args.n-1} bit.')
-    print(f' *')
-    print(f' * Each code is packed left-aligned into {2**args.n // 8} bytes in big-endian byte order.')
-    print(f' */')
-    print(f'const uint8_t gold_code_{args.n}bit[] = {{')
-    for i, code in enumerate(gold(args.n)):
-        par = ' '.join(f'0x{d:02x},' for d in np.packbits(code)) + f' /* {i: 3d} "{"".join(str(x) for x in code)}" */'
-        print(textwrap.fill(par, initial_indent=' '*4, subsequent_indent=' '*4, width=120))
-    print('};')
-    print()
-    print(f'const uint8_t * const gold_code_table __attribute__((weak)) = gold_code_{args.n}bit;')
+    if not args.header != args.source:
+        print('Exactly one of --header and --source must be given.', file=sys.stderr)
+        sys.exit(1)
+
+    nbytes = math.ceil((2**args.n-1)/8)
+
+    if args.source:
+        print('/* THIS IS A GENERATED FILE. DO NOT EDIT! */')
+        print('#include <unistd.h>')
+        print('#include <stdint.h>')
+        print()
+        print(f'/* {args.n} bit gold sequences: {2**args.n+1} sequences of length {2**args.n-1} bit.')
+        print(f' *')
+        print(f' * Each code is packed left-aligned into {nbytes} bytes in big-endian byte order.')
+        print(f' */')
+        print(f'const uint8_t gold_code_{args.n}bit[{2**args.n+1}][{nbytes}] = {{')
+        for i, code in enumerate(gold(args.n)):
+            par = '{' + ' '.join(f'0x{d:02x},' for d in np.packbits(code)) + f'}}, /* {i: 3d} "{"".join(str(x) for x in code)}" */'
+            print(textwrap.fill(par, initial_indent=' '*4, subsequent_indent=' '*4, width=120))
+        print('};')
+        print()
+        print(f'const uint8_t * const {args.variable} __attribute__((weak)) = (uint8_t *const)gold_code_{args.n}bit;')
+        print(f'const size_t {args.variable}_nbits __attribute__((weak)) = {args.n};')
+    else:
+        print('/* THIS IS A GENERATED FILE. DO NOT EDIT! */')
+        with print_include_guards(f'__GOLD_CODE_GENERATED_HEADER_{args.n}__'):
+            print(f'extern const uint8_t gold_code_{args.n}bit[{2**args.n+1}][{nbytes}];')
+
+        with print_include_guards(f'__GOLD_CODE_GENERATED_HEADER_GLOBAL_SYM_{args.variable.upper()}__'):
+            print(f'extern const uint8_t {args.variable}[{2**args.n+1}][{nbytes}];')
+            print(f'extern const size_t {args.variable}_nbits;')