diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/spkmodem_recv/spkmodem-recv.c | 36 |
1 files changed, 19 insertions, 17 deletions
diff --git a/util/spkmodem_recv/spkmodem-recv.c b/util/spkmodem_recv/spkmodem-recv.c index d1fc6a34..903d6830 100644 --- a/util/spkmodem_recv/spkmodem-recv.c +++ b/util/spkmodem_recv/spkmodem-recv.c @@ -24,7 +24,7 @@ #define ERR() (errno = errno ? errno : ECANCELED) signed short frame[2 * SAMPLES_PER_FRAME], pulse[2 * SAMPLES_PER_FRAME]; -int f1, f2, lp, ascii_bit = 7; +int freq_data, freq_separator, sample_count, ascii_bit = 7; char ascii = 0; void handle_audio(void); @@ -56,24 +56,24 @@ main(int argc, char *argv[]) void handle_audio(void) { - static int llp = 0; - if (lp > (3 * SAMPLES_PER_FRAME)) { + static int flush_count = 0; + if (sample_count > (3 * SAMPLES_PER_FRAME)) { ascii_bit = 7; - ascii = lp = 0; - ++llp; + ascii = sample_count = 0; + ++flush_count; } - if (llp == FLUSH_TIMEOUT) + if (flush_count == FLUSH_TIMEOUT) /* TODO: reset flush count? */ if (fflush(stdout) == EOF) err(ERR(), NULL); - if ((f2 <= FREQ_SEP_MIN) || (f2 >= FREQ_SEP_MAX) - || (f1 <= FREQ_DATA_MIN) || (f1 >= FREQ_DATA_MAX)) { + if ((freq_separator <= FREQ_SEP_MIN) || (freq_separator >= FREQ_SEP_MAX) + || (freq_data <= FREQ_DATA_MIN) || (freq_data >= FREQ_DATA_MAX)) { fetch_sample(); return; } if (!set_ascii_bit()) print_char(); - lp = llp = 0; + sample_count = flush_count = 0; for (int sample = 0; sample < SAMPLES_PER_FRAME; sample++) fetch_sample(); } @@ -82,16 +82,18 @@ void fetch_sample(void) { static int ringpos = 0; - f1 -= pulse[ringpos]; - f1 += pulse[(ringpos + SAMPLES_PER_FRAME) % (2 * SAMPLES_PER_FRAME)]; - f2 -= pulse[(ringpos + SAMPLES_PER_FRAME) % (2 * SAMPLES_PER_FRAME)]; + freq_data -= pulse[ringpos]; + freq_data += pulse[(ringpos + SAMPLES_PER_FRAME) + % (2 * SAMPLES_PER_FRAME)]; + freq_separator -= pulse[(ringpos + SAMPLES_PER_FRAME) + % (2 * SAMPLES_PER_FRAME)]; read_frame(ringpos); if ((pulse[ringpos] = (abs(frame[ringpos]) > THRESHOLD) ? 1 : 0)) - ++f2; + ++freq_separator; ++ringpos; ringpos %= 2 * SAMPLES_PER_FRAME; - ++lp; + ++sample_count; } void @@ -109,10 +111,10 @@ set_ascii_bit(void) long stdin_pos = 0; if ((stdin_pos = ftell(stdin)) == -1) err(ERR(), NULL); - printf ("%d %d %d @%ld\n", f1, f2, FREQ_DATA_THRESHOLD, - stdin_pos - sizeof(frame)); + printf ("%d %d %d @%ld\n", freq_data, freq_separator, + FREQ_DATA_THRESHOLD, stdin_pos - sizeof(frame)); #endif - if (f1 < FREQ_DATA_THRESHOLD) + if (freq_data < FREQ_DATA_THRESHOLD) ascii |= (1 << ascii_bit); return ascii_bit; } |