1 files changed, 109 insertions, 0 deletions
diff --git a/fw/tools/dsss_demod_test.c b/fw/tools/dsss_demod_test.c
new file mode 100644
index 0000000..f7df111
--- /dev/null
+++ b/fw/tools/dsss_demod_test.c
@@ -0,0 +1,109 @@
+
+#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 handle_dsss_received(symbol_t data[static TRANSMISSION_SYMBOLS]) {
+    printf("data sequence received: [ ");
+    for (size_t i=0; i<TRANSMISSION_SYMBOLS; i++) {
+        //printf("%+3d", ((data[i]&1) ? 1 : -1) * (data[i]>>1));
+        printf("%2d", data[i]);
+        if (i+1 < TRANSMISSION_SYMBOLS)
+            printf(", ");
+    }
+    printf(" ]\n");
+}
+
+void print_usage() {
+    fprintf(stderr, "Usage: dsss_demod_test [test_data.bin] [optional recording channel number]\n");
+}
+
+int main(int argc, char **argv) {
+    if (argc != 2 && argc != 3) {
+        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 > 10000000) {
+        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;
+    }
+
+    int record_channel = -1;
+    if (argc == 3) {
+        char *endptr;
+        record_channel = strtoul(argv[2], &endptr, 10);
+        if (!endptr || *endptr != '\0') {
+            fprintf(stderr, "Invalid channel number \"%s\"\n", argv[2]);
+            return 1;
+        }
+    }
+
+    if (record_channel != -1)
+        fprintf(stderr, "Reading %zd samples test data...", st.st_size/sizeof(float));
+    ssize_t nread = 0;
+    while (nread < st.st_size) {
+        ssize_t rc = read(fd, buf + nread, 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;
+    }
+    if (record_channel != -1)
+        fprintf(stderr, " done.\n");
+
+    const size_t n_samples = st.st_size / sizeof(float);
+    float *buf_f = (float *)buf;
+
+    if (record_channel != -1)
+        fprintf(stderr, "Starting simulation.\n");
+
+    struct dsss_demod_state demod;
+    dsss_demod_init(&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);
+    }
+
+    free(buf);
+    return 0;
+}