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/* -*- c++ -*- */
/*
* Copyright 2004,2010,2013 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* SPDX-License-Identifier: GPL-3.0-or-later
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "check_lfsr_32k_s_impl.h"
#include <gnuradio/io_signature.h>
#include <cstdio>
#include <cstdlib>
namespace gr {
namespace blocks {
check_lfsr_32k_s::sptr check_lfsr_32k_s::make()
{
return gnuradio::make_block_sptr<check_lfsr_32k_s_impl>();
}
check_lfsr_32k_s_impl::check_lfsr_32k_s_impl()
: sync_block("check_lfsr_32k",
io_signature::make(1, 1, sizeof(short)),
io_signature::make(0, 0, 0)),
d_state(SEARCHING),
d_history(0),
d_ntotal(0),
d_nright(0),
d_runlength(0),
d_index(0)
{
lfsr_32k lfsr;
for (int i = 0; i < BUFSIZE; i++)
d_buffer[i] = lfsr.next_short();
enter_SEARCHING();
}
check_lfsr_32k_s_impl::~check_lfsr_32k_s_impl() {}
int check_lfsr_32k_s_impl::work(int noutput_items,
gr_vector_const_void_star& input_items,
gr_vector_void_star& output_items)
{
unsigned short* in = (unsigned short*)input_items[0];
for (int i = 0; i < noutput_items; i++) {
unsigned short x = in[i];
unsigned short expected;
switch (d_state) {
case MATCH0:
if (x == d_buffer[0])
enter_MATCH1();
break;
case MATCH1:
if (x == d_buffer[1])
enter_MATCH2();
else
enter_MATCH0();
break;
case MATCH2:
if (x == d_buffer[2])
enter_LOCKED();
else
enter_MATCH0();
break;
case LOCKED:
expected = d_buffer[d_index];
d_index = d_index + 1;
if (d_index >= BUFSIZE)
d_index = 0;
if (x == expected)
right();
else {
wrong();
log_error(expected, x);
if (wrong_three_times())
enter_SEARCHING();
}
break;
default:
abort();
}
d_ntotal++;
}
return noutput_items;
}
void check_lfsr_32k_s_impl::enter_SEARCHING()
{
d_state = SEARCHING;
wrong(); // reset history
wrong();
wrong();
d_runlength = 0;
d_index = 0; // reset LFSR to beginning
if (0)
fprintf(stdout,
"check_lfsr_32k: enter_SEARCHING at offset %8ld (0x%08lx)\n",
d_ntotal,
d_ntotal);
enter_MATCH0();
}
void check_lfsr_32k_s_impl::enter_MATCH0() { d_state = MATCH0; }
void check_lfsr_32k_s_impl::enter_MATCH1() { d_state = MATCH1; }
void check_lfsr_32k_s_impl::enter_MATCH2() { d_state = MATCH2; }
void check_lfsr_32k_s_impl::enter_LOCKED()
{
d_state = LOCKED;
right(); // setup history
right();
right();
d_index = 3; // already matched first 3 items
if (0)
fprintf(stdout,
"check_lfsr_32k: enter_LOCKED at offset %8ld (0x%08lx)\n",
d_ntotal,
d_ntotal);
}
void check_lfsr_32k_s_impl::log_error(unsigned short expected, unsigned short actual)
{
if (0)
fprintf(stdout,
"check_lfsr_32k: expected %5d (0x%04x) got %5d (0x%04x) offset %8ld "
"(0x%08lx)\n",
expected,
expected,
actual,
actual,
d_ntotal,
d_ntotal);
}
} /* namespace blocks */
} /* namespace gr */
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