Permalink
Fetching contributors…
Cannot retrieve contributors at this time
1332 lines (1136 sloc) 37.3 KB
// ----------------------------------------------------------------------------
// cw.cxx -- morse code modem
//
// Copyright (C) 2006-2010
// Dave Freese, W1HKJ
// (C) Mauri Niininen, AG1LE
//
// This file is part of fldigi. Adapted from code contained in gmfsk source code
// distribution.
// gmfsk Copyright (C) 2001, 2002, 2003
// Tomi Manninen (oh2bns@sral.fi)
// Copyright (C) 2004
// Lawrence Glaister (ve7it@shaw.ca)
//
// Fldigi is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Fldigi is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with fldigi. If not, see <http://www.gnu.org/licenses/>.
// ----------------------------------------------------------------------------
#include <config.h>
#include <cstring>
#include <string>
#include <stdio.h>
#include <iostream>
#include <fstream>
#include <cstdlib>
#include "digiscope.h"
#include "waterfall.h"
#include "fl_digi.h"
#include "fftfilt.h"
#include "cw.h"
#include "misc.h"
#include "configuration.h"
#include "confdialog.h"
#include "status.h"
#include "debug.h"
#include "FTextRXTX.h"
#include "modem.h"
#include "qrunner.h"
using namespace std;
#define XMT_FILT_LEN 256
#define QSK_DELAY_LEN 4*XMT_FILT_LEN
const cw::SOM_TABLE cw::som_table[] = {
/* Prosigns */
{'=', "<BT>", {1.0, 0.33, 0.33, 0.33, 1.0, 0, 0} }, // 0
{'~', "<AA>", { 0.33, 1.0, 0.33, 1.0, 0, 0, 0} }, // 1
{'%', "<AS>", { 0.33, 1.0, 0.33, 0.33, 0.33, 0, 0} }, // 2
{'+', "<AR>", { 0.33, 1.0, 0.33, 1.0, 0.33, 0, 0} }, // 3
{'>', "<SK>", { 0.33, 0.33, 0.33, 1.0, 0.33, 1.0, 0} }, // 4
{'<', "<KN>", {1.0, 0.33, 1.0, 1.0, 0.33, 0, 0} }, // 5
{'&', "<INT>", { 0.33, 0.33, 1.0, 0.33, 1.0, 0, 0} }, // 6
{'}', "<HM>", { 0.33, 0.33, 0.33, 0.33, 1.0, 1.0, 0} }, // 7
{'{', "<VE>", { 0.33, 0.33, 0.33, 1.0, 0.33, 0, 0} }, // 8
/* ASCII 7bit letters */
{'A', "A", { 0.33, 1.0, 0, 0, 0, 0, 0} },
{'B', "B", {1.0, 0.33, 0.33, 0.33, 0, 0, 0} },
{'C', "C", {1.0, 0.33, 1.0, 0.33, 0, 0, 0} },
{'D', "D", {1.0, 0.33, 0.33, 0, 0, 0, 0} },
{'E', "E", { 0.33, 0, 0, 0, 0, 0, 0} },
{'F', "F", { 0.33, 0.33, 1.0, 0.33, 0, 0, 0} },
{'G', "G", {1.0, 1.0, 0.33, 0, 0, 0, 0} },
{'H', "H", { 0.33, 0.33, 0.33, 0.33, 0, 0, 0} },
{'I', "I", { 0.33, 0.33, 0, 0, 0, 0, 0} },
{'J', "J", { 0.33, 1.0, 1.0, 1.0, 0, 0, 0} },
{'K', "K", {1.0, 0.33, 1.0, 0, 0, 0, 0} },
{'L', "L", { 0.33, 1.0, 0.33, 0.33, 0, 0, 0} },
{'M', "M", {1.0, 1.0, 0, 0, 0, 0, 0} },
{'N', "N", {1.0, 0.33, 0, 0, 0, 0, 0} },
{'O', "O", {1.0, 1.0, 1.0, 0, 0, 0, 0} },
{'P', "P", { 0.33, 1.0, 1.0, 0.33, 0, 0, 0} },
{'Q', "Q", {1.0, 1.0, 0.33, 1.0, 0, 0, 0} },
{'R', "R", { 0.33, 1.0, 0.33, 0, 0, 0, 0} },
{'S', "S", { 0.33, 0.33, 0.33, 0, 0, 0, 0} },
{'T', "T", {1.0, 0, 0, 0, 0, 0, 0} },
{'U', "U", { 0.33, 0.33, 1.0, 0, 0, 0, 0} },
{'V', "V", { 0.33, 0.33, 0.33, 1.0, 0, 0, 0} },
{'W', "W", { 0.33, 1.0, 1.0, 0, 0, 0, 0} },
{'X', "X", {1.0, 0.33, 0.33, 1.0, 0, 0, 0} },
{'Y', "Y", {1.0, 0.33, 1.0, 1.0, 0, 0, 0} },
{'Z', "Z", {1.0, 1.0, 0.33, 0.33, 0, 0, 0} },
/* Numerals */
{'0', "0", {1.0, 1.0, 1.0, 1.0, 1.0, 0, 0} },
{'1', "1", { 0.33, 1.0, 1.0, 1.0, 1.0, 0, 0} },
{'2', "2", { 0.33, 0.33, 1.0, 1.0, 1.0, 0, 0} },
{'3', "3", { 0.33, 0.33, 0.33, 1.0, 1.0, 0, 0} },
{'4', "4", { 0.33, 0.33, 0.33, 0.33, 1.0, 0, 0} },
{'5', "5", { 0.33, 0.33, 0.33, 0.33, 0.33, 0, 0} },
{'6', "6", {1.0, 0.33, 0.33, 0.33, 0.33, 0, 0} },
{'7', "7", {1.0, 1.0, 0.33, 0.33, 0.33, 0, 0} },
{'8', "8", {1.0, 1.0, 1.0, 0.33, 0.33, 0, 0} },
{'9', "9", {1.0, 1.0, 1.0, 1.0, 0.33, 0, 0} },
/* Punctuation */
{'\\', "\\", { 0.33, 1.0, 0.33, 0.33, 1.0, 0.33, 0} },
{'\'', "'", { 0.33, 1.0, 1.0, 1.0, 1.0, 0.33, 0} },
{'$', "$", { 0.33, 0.33, 0.33, 1.0, 0.33, 0.33,1.0} },
{'(', "(", {1.0, 0.33, 1.0, 1.0, 0.33, 0, 0} },
{')', ")", {1.0, 0.33, 1.0, 1.0, 0.33, 1.0, 0} },
{',', ",", {1.0, 1.0, 0.33, 0.33, 1.0, 1.0, 0} },
{'-', "-", {1.0, 0.33, 0.33, 0.33, 0.33, 1.0, 0} },
{'.', ".", { 0.33, 1.0, 0.33, 1.0, 0.33, 1.0, 0} },
{'/', "/", {1.0, 0.33, 0.33, 1.0, 0.33, 0, 0} },
{':', ":", {1.0, 1.0, 1.0, 0.33, 0.33, 0.33, 0} },
{';', ";", {1.0, 0.33, 1.0, 0.33, 1.0, 0.33, 0} },
{'?', "?", { 0.33, 0.33, 1.0, 1.0, 0.33, 0.33, 0} },
{'_', "_", { 0.33, 0.33, 1.0, 1.0, 0.33, 1.0, 0} },
{'@', "@", { 0.33, 1.0, 1.0, 0.33, 1.0, 0.33, 0} },
{'!', "!", {1.0, 0.33, 1.0, 0.33, 1.0, 1.0, 0} },
{0, NULL, {0.0}}
};
int cw::normalize(float *v, int n, int twodots)
{
if( n == 0 ) return 0 ;
float max = v[0];
float min = v[0];
int j;
/* find max and min values */
for (j=1; j<n; j++) {
float vj = v[j];
if (vj > max) max = vj;
else if (vj < min) min = vj;
}
/* all values 0 - no need to normalize or decode */
if (max == 0.0) return 0;
/* scale values between [0,1] -- if Max longer than 2 dots it was "dah" and should be 1.0, otherwise it was "dit" and should be 0.33 */
float ratio = (max > twodots) ? 1.0 : 0.33 ;
ratio /= max ;
for (j=0; j<n; j++) v[j] *= ratio;
return (1);
}
const char * cw::find_winner (float *inbuf, int twodots)
{
float diffsf = 999999999999.0;
if ( normalize (inbuf, WGT_SIZE, twodots) == 0) return NULL;
const SOM_TABLE * winner = NULL;
for ( const SOM_TABLE * som = som_table; som->chr != 0; som++) {
/* Compute the distance between codebook and input entry */
float difference = 0.0;
for (int i = 0; i < WGT_SIZE; i++) {
float diff = (inbuf[i] - som->wgt[i]);
difference += diff * diff;
if (difference > diffsf) break;
}
/* If distance is smaller than previous distances */
if (difference < diffsf) {
winner = som;
diffsf = difference;
}
}
if (winner != NULL)
return winner->prt;
else
return NULL;
}
void cw::tx_init(SoundBase *sc)
{
scard = sc;
phaseacc = 0;
lastsym = 0;
qskphase = 0;
if (progdefaults.pretone) pretone();
symbols = 0;
acc_symbols = 0;
ovhd_symbols = 0;
cw_xmt_filter->create_filter(lwr, upr);
qsk_ptr = XMT_FILT_LEN / 2;
maxval = 0.0;
}
void cw::rx_init()
{
cw_receive_state = RS_IDLE;
smpl_ctr = 0;
cw_rr_current = 0;
cw_ptr = 0;
agc_peak = 0;
set_scope_mode(Digiscope::SCOPE);
update_Status();
usedefaultWPM = false;
scope_clear = true;
}
void cw::init()
{
bool wfrev = wf->Reverse();
bool wfsb = wf->USB();
reverse = wfrev ^ !wfsb;
if (progdefaults.StartAtSweetSpot)
set_freq(progdefaults.CWsweetspot);
else if (progStatus.carrier != 0) {
set_freq(progStatus.carrier);
#if !BENCHMARK_MODE
progStatus.carrier = 0;
#endif
} else
set_freq(wf->Carrier());
trackingfilter->reset();
cw_adaptive_receive_threshold = (long int)trackingfilter->run(2 * cw_send_dot_length);
put_cwRcvWPM(cw_send_speed);
for (int i = 0; i < OUTBUFSIZE; i++)
outbuf[i] = qskbuf[i] = 0.0;
rx_init();
use_paren = progdefaults.CW_use_paren;
prosigns = progdefaults.CW_prosigns;
stopflag = false;
maxval = 0;
}
cw::~cw() {
if (hilbert) delete hilbert;
if (cw_FIR_filter) delete cw_FIR_filter;
if (cw_FFT_filter) delete cw_FFT_filter;
if (cw_xmt_filter) delete cw_xmt_filter;
if (bitfilter) delete bitfilter;
if (trackingfilter) delete trackingfilter;
}
cw::cw() : modem()
{
cap |= CAP_BW;
mode = MODE_CW;
freqlock = false;
usedefaultWPM = false;
frequency = progdefaults.CWsweetspot;
tx_frequency = get_txfreq_woffset();
risetime = progdefaults.CWrisetime;
QSKshape = progdefaults.QSKshape;
cw_ptr = 0;
clrcount = CLRCOUNT;
samplerate = CWSampleRate;
fragmentsize = CWMaxSymLen;
cw_speed = progdefaults.CWspeed;
bandwidth = progdefaults.CWbandwidth;
cw_send_speed = cw_speed;
cw_receive_speed = cw_speed;
cw_adaptive_receive_threshold = 2 * DOT_MAGIC / cw_speed;
cw_noise_spike_threshold = cw_adaptive_receive_threshold / 4;
cw_send_dot_length = DOT_MAGIC / cw_send_speed;
cw_send_dash_length = 3 * cw_send_dot_length;
symbollen = (int)round(samplerate * 1.2 / progdefaults.CWspeed);
fsymlen = (int)round(samplerate * 1.2 / progdefaults.CWfarnsworth);
memset(rx_rep_buf, 0, sizeof(rx_rep_buf));
// block of variables that get updated each time speed changes
pipesize = (22 * samplerate * 12) / (progdefaults.CWspeed * 160);
if (pipesize < 0) pipesize = 512;
if (pipesize > MAX_PIPE_SIZE) pipesize = MAX_PIPE_SIZE;
cwTrack = true;
phaseacc = 0.0;
FFTphase = 0.0;
FIRphase = 0.0;
FFTvalue = 0.0;
FIRvalue = 0.0;
pipeptr = 0;
clrcount = 0;
upper_threshold = progdefaults.CWupper;
lower_threshold = progdefaults.CWlower;
for (int i = 0; i < MAX_PIPE_SIZE; clearpipe[i++] = 0.0);
agc_peak = 1.0;
in_replay = 0;
use_fft_filter = progdefaults.CWuse_fft_filter;
use_matched_filter = progdefaults.CWmfilt;
bandwidth = progdefaults.CWbandwidth;
if (use_matched_filter)
progdefaults.CWbandwidth = bandwidth = 2.0 * progdefaults.CWspeed / 1.2;
hilbert = new C_FIR_filter(); // hilbert transform used by FFT filter
hilbert->init_hilbert(37, 1);
cw_FIR_filter = new C_FIR_filter();
cw_FIR_filter->init_lowpass (CW_FIRLEN, DEC_RATIO, progdefaults.CWspeed/(1.2 * samplerate));
//overlap and add filter length should be a factor of 2
// low pass implementation
FilterFFTLen = 4096;
cw_FFT_filter = new fftfilt(progdefaults.CWspeed/(1.2 * samplerate), FilterFFTLen);
// transmit filtering
nbfreq = frequency;
nbpf = progdefaults.CW_bpf;
lwr = nbfreq - nbpf/2.0;
upr = nbfreq + nbpf/2.0;
if (lwr < 50.0) lwr = 50.0;
if (upr > 3900.0) upr = 3900.0;
lwr /= samplerate;
upr /= samplerate;
xmt_signal = new double[XMT_FILT_LEN];
for (int i = 0; i < XMT_FILT_LEN; i++) xmt_signal[i] = 0.0;
qsk_signal = new double[QSK_DELAY_LEN];
for (int i = 0; i < QSK_DELAY_LEN; i++) qsk_signal[i] = 0.0;
cw_xmt_filter = new fftfilt( lwr, upr, 2*XMT_FILT_LEN);// transmit filter length
// FilterFFTLen);
// bit filter based on 10 msec rise time of CW waveform
int bfv = (int)(samplerate * .010 / DEC_RATIO);
bitfilter = new Cmovavg(bfv);
trackingfilter = new Cmovavg(TRACKING_FILTER_SIZE);
makeshape();
sync_parameters();
REQ(static_cast<void (waterfall::*)(int)>(&waterfall::Bandwidth), wf, (int)bandwidth);
REQ(static_cast<int (Fl_Value_Slider2::*)(double)>(&Fl_Value_Slider2::value), sldrCWbandwidth, (int)bandwidth);
update_Status();
}
// SHOULD ONLY BE CALLED FROM THE rx_processing loop
void cw::reset_rx_filter()
{
if (use_fft_filter != progdefaults.CWuse_fft_filter ||
use_matched_filter != progdefaults.CWmfilt ||
cw_speed != progdefaults.CWspeed ||
(bandwidth != progdefaults.CWbandwidth && !use_matched_filter)) {
use_fft_filter = progdefaults.CWuse_fft_filter;
use_matched_filter = progdefaults.CWmfilt;
cw_send_speed = cw_speed = progdefaults.CWspeed;
if (use_matched_filter)
progdefaults.CWbandwidth = bandwidth = 2.0 * progdefaults.CWspeed / 1.2;
else
bandwidth = progdefaults.CWbandwidth;
double fbw = 0.5 * bandwidth / samplerate;
if (use_fft_filter) { // FFT filter
cw_FFT_filter->create_lpf(fbw);
FFTphase = 0;
} else { // FIR filter
cw_FIR_filter->init_lowpass (CW_FIRLEN, DEC_RATIO, fbw);
FIRphase = 0;
}
REQ(static_cast<void (waterfall::*)(int)>(&waterfall::Bandwidth),
wf, (int)bandwidth);
REQ(static_cast<int (Fl_Value_Slider2::*)(double)>(&Fl_Value_Slider2::value),
sldrCWbandwidth, (int)bandwidth);
pipesize = (22 * samplerate * 12) / (progdefaults.CWspeed * 160);
if (pipesize < 0) pipesize = 512;
if (pipesize > MAX_PIPE_SIZE) pipesize = MAX_PIPE_SIZE;
cw_adaptive_receive_threshold = 2 * DOT_MAGIC / cw_speed;
cw_noise_spike_threshold = cw_adaptive_receive_threshold / 4;
cw_send_dot_length = DOT_MAGIC / cw_send_speed;
cw_send_dash_length = 3 * cw_send_dot_length;
symbollen = (int)round(samplerate * 1.2 / progdefaults.CWspeed);
fsymlen = (int)round(samplerate * 1.2 / progdefaults.CWfarnsworth);
phaseacc = 0.0;
FFTphase = 0.0;
FIRphase = 0.0;
FFTvalue = 0.0;
FIRvalue = 0.0;
pipeptr = 0;
clrcount = 0;
smpl_ctr = 0;
memset(rx_rep_buf, 0, sizeof(rx_rep_buf));
agc_peak = 0;
clear_syncscope();
}
if (lower_threshold != progdefaults.CWlower ||
upper_threshold != progdefaults.CWupper) {
lower_threshold = progdefaults.CWlower;
upper_threshold = progdefaults.CWupper;
clear_syncscope();
}
}
// sync_parameters()
// Synchronize the dot, dash, end of element, end of character, and end
// of word timings and ranges to new values of Morse speed, or receive tolerance.
void cw::sync_transmit_parameters()
{
wpm = usedefaultWPM ? progdefaults.defCWspeed : progdefaults.CWspeed;
fwpm = progdefaults.CWfarnsworth;
cw_send_dot_length = DOT_MAGIC / progdefaults.CWspeed;
cw_send_dash_length = 3 * cw_send_dot_length;
nusymbollen = (int)round(samplerate * 1.2 / wpm);
nufsymlen = (int)round(samplerate * 1.2 / fwpm);
if (symbollen != nusymbollen ||
nufsymlen != fsymlen ||
risetime != progdefaults.CWrisetime ||
QSKshape != progdefaults.QSKshape) {
risetime = progdefaults.CWrisetime;
QSKshape = progdefaults.QSKshape;
symbollen = nusymbollen;
fsymlen = nufsymlen;
makeshape();
}
}
void cw::sync_parameters()
{
sync_transmit_parameters();
// check if user changed the tracking or the cw default speed
if ((cwTrack != progdefaults.CWtrack) ||
(cw_send_speed != progdefaults.CWspeed)) {
trackingfilter->reset();
cw_adaptive_receive_threshold = 2 * cw_send_dot_length;
put_cwRcvWPM(cw_send_speed);
}
cwTrack = progdefaults.CWtrack;
cw_send_speed = progdefaults.CWspeed;
// Receive parameters:
lowerwpm = cw_send_speed - progdefaults.CWrange;
upperwpm = cw_send_speed + progdefaults.CWrange;
if (lowerwpm < progdefaults.CWlowerlimit)
lowerwpm = progdefaults.CWlowerlimit;
if (upperwpm > progdefaults.CWupperlimit)
upperwpm = progdefaults.CWupperlimit;
cw_lower_limit = 2 * DOT_MAGIC / upperwpm;
cw_upper_limit = 2 * DOT_MAGIC / lowerwpm;
if (cwTrack)
cw_receive_speed = DOT_MAGIC / (cw_adaptive_receive_threshold / 2);
else {
cw_receive_speed = cw_send_speed;
cw_adaptive_receive_threshold = 2 * cw_send_dot_length;
}
if (cw_receive_speed > 0)
cw_receive_dot_length = DOT_MAGIC / cw_receive_speed;
else
cw_receive_dot_length = DOT_MAGIC / 5;
cw_receive_dash_length = 3 * cw_receive_dot_length;
cw_noise_spike_threshold = cw_receive_dot_length / 2;
}
//=======================================================================
// cw_update_tracking()
// This gets called everytime we have a dot dash sequence or a dash dot
// sequence. Since we have semi validated tone durations, we can try and
// track the cw speed by adjusting the cw_adaptive_receive_threshold variable.
// This is done with moving average filters for both dot & dash.
//=======================================================================
void cw::update_tracking(int idot, int idash)
{
int dot, dash;
if (idot > cw_lower_limit && idot < cw_upper_limit)
dot = idot;
else
dot = cw_send_dot_length;
if (idash > cw_lower_limit && idash < cw_upper_limit)
dash = idash;
else
dash = cw_send_dash_length;
cw_adaptive_receive_threshold = (long int)trackingfilter->run((dash + dot) / 2);
// if (!use_matched_filter)
sync_parameters();
}
//=======================================================================
//update_syncscope()
//Routine called to update the display on the sync scope display.
//For CW this is an o scope pattern that shows the cw data stream.
//=======================================================================
void cw::update_Status()
{
put_MODEstatus("CW %s Rx %d", usedefaultWPM ? "*" : " ", cw_receive_speed);
}
//=======================================================================
//update_syncscope()
//Routine called to update the display on the sync scope display.
//For CW this is an o scope pattern that shows the cw data stream.
//=======================================================================
//
void cw::update_syncscope()
{
if (pipesize < 0 || pipesize > MAX_PIPE_SIZE)
return;
for (int i = 0; i < pipesize; i++)
scopedata[i] = 0.96*pipe[i]+0.02;
set_scope_xaxis_1(progdefaults.CWupper);
set_scope_xaxis_2(progdefaults.CWlower);
set_scope(scopedata, pipesize, true);
scopedata.next(); // change buffers
clrcount = CLRCOUNT;
put_cwRcvWPM(cw_receive_speed);
update_Status();
}
void cw::clear_syncscope()
{
set_scope_xaxis_1(upper_threshold);
set_scope_xaxis_2(lower_threshold);
set_scope(clearpipe, pipesize, false);
clrcount = CLRCOUNT;
}
cmplx cw::mixer(cmplx in)
{
cmplx z (cos(phaseacc), sin(phaseacc));
z = z * in;
phaseacc += TWOPI * frequency / samplerate;
if (phaseacc > TWOPI) phaseacc -= TWOPI;
return z;
}
//=====================================================================
// cw_rxprocess()
// Called with a block (size SCBLOCKSIZE samples) of audio.
//
//======================================================================
void cw::decode_stream(double value)
{
const char *c, *somc;
char *cptr;
// Compute a variable threshold value for tone detection
// Fast attack and slow decay.
if (value > agc_peak)
agc_peak = decayavg(agc_peak, value, 20);
else
agc_peak = decayavg(agc_peak, value, 800);
metric = clamp(agc_peak * 2e3 , 0.0, 100.0);
// save correlation amplitude value for the sync scope
// normalize if possible
if (agc_peak)
value /= agc_peak;
else
value = 0;
pipe[pipeptr] = value;
if (++pipeptr == pipesize) pipeptr = 0;
if (!progStatus.sqlonoff || metric > progStatus.sldrSquelchValue ) {
// Power detection using hysterisis detector
// upward trend means tone starting
if ((value > progdefaults.CWupper) && (cw_receive_state != RS_IN_TONE)) {
handle_event(CW_KEYDOWN_EVENT, NULL);
}
// downward trend means tone stopping
if ((value < progdefaults.CWlower) && (cw_receive_state == RS_IN_TONE)) {
handle_event(CW_KEYUP_EVENT, NULL);
}
}
if (handle_event(CW_QUERY_EVENT, &c) == CW_SUCCESS) {
update_syncscope();
if (progdefaults.CWuseSOMdecoding) {
somc = find_winner(cw_buffer, cw_adaptive_receive_threshold);
cptr = (char*)somc;
if (somc != NULL) {
while (*cptr != '\0')
put_rx_char(progdefaults.rx_lowercase ? tolower(*cptr++) : *cptr++,FTextBase::CTRL);
}
if (strlen(c) == 1 && *c == ' ')
put_rx_char(progdefaults.rx_lowercase ? tolower(*c) : *c);
cw_ptr = 0;
memset(cw_buffer, 0, sizeof(cw_buffer));
} else {
if (strlen(c) == 1)
put_rx_char(progdefaults.rx_lowercase ? tolower(*c) : *c);
else while (*c)
put_rx_char(progdefaults.rx_lowercase ? tolower(*c++) : *c++, FTextBase::CTRL);
}
}
}
void cw::rx_FFTprocess(const double *buf, int len)
{
cmplx z, *zp;
int n;
while (len-- > 0) {
z = cmplx ( *buf * cos(FFTphase), *buf * sin(FFTphase) );
FFTphase += TWOPI * frequency / samplerate;
if (FFTphase > TWOPI) FFTphase -= TWOPI;
buf++;
n = cw_FFT_filter->run(z, &zp); // n = 0 or filterlen/2
if (!n) continue;
for (int i = 0; i < n; i++) {
// update the basic sample counter used for morse timing
++smpl_ctr;
if (smpl_ctr % DEC_RATIO) continue; // decimate by DEC_RATIO
// demodulate
FFTvalue = abs(zp[i]);
FFTvalue = bitfilter->run(FFTvalue);
decode_stream(FFTvalue);
} // for (i =0; i < n ...
} //while (len-- > 0)
}
void cw::rx_FIRprocess(const double *buf, int len)
{
cmplx z;
while (len-- > 0) {
z = cmplx ( *buf * cos(FIRphase), *buf * sin(FIRphase) );
buf++;
FIRphase += TWOPI * frequency / samplerate;
if (FIRphase > TWOPI) FIRphase -= TWOPI;
if (cw_FIR_filter->run ( z, z )) {
// update the basic sample counter used for morse timing
smpl_ctr += DEC_RATIO;
// demodulate
FIRvalue = abs(z);
FIRvalue = bitfilter->run(FIRvalue);
decode_stream(FIRvalue);
}
}
}
static bool cwprocessing = false;
int cw::rx_process(const double *buf, int len)
{
if (cwprocessing) return 0;
cwprocessing = true;
reset_rx_filter();
if (use_fft_filter)
rx_FFTprocess(buf, len);
else
rx_FIRprocess(buf, len);
if (!clrcount--) clear_syncscope();
display_metric(metric);
cwprocessing = false;
return 0;
}
// ----------------------------------------------------------------------
// Compare two timestamps, and return the difference between them in usecs.
int cw::usec_diff(unsigned int earlier, unsigned int later)
{
// Compare the timestamps.
// At 4 WPM, the dash length is 3*(1200000/4)=900,000 usecs, and
// the word gap is 2,100,000 usecs.
if (earlier >= later) {
return 0;
} else
return (int) (((double) (later - earlier) * USECS_PER_SEC) / samplerate);
}
//=======================================================================
// handle_event()
// high level cw decoder... gets called with keyup, keydown, reset and
// query commands.
// Keyup/down influences decoding logic.
// Reset starts everything out fresh.
// The query command returns CW_SUCCESS and the character that has
// been decoded (may be '*',' ' or [a-z,0-9] or a few others)
// If there is no data ready, CW_ERROR is returned.
//=======================================================================
int cw::handle_event(int cw_event, const char **c)
{
static int space_sent = true; // for word space logic
static int last_element = 0; // length of last dot/dash
int element_usec; // Time difference in usecs
switch (cw_event) {
case CW_RESET_EVENT:
sync_parameters();
cw_receive_state = RS_IDLE;
cw_rr_current = 0; // reset decoding pointer
cw_ptr = 0;
memset(cw_buffer, 0, sizeof(cw_buffer));
smpl_ctr = 0; // reset audio sample counter
memset(rx_rep_buf, 0, sizeof(rx_rep_buf));
break;
case CW_KEYDOWN_EVENT:
// A receive tone start can only happen while we
// are idle, or in the middle of a character.
if (cw_receive_state == RS_IN_TONE)
return CW_ERROR;
// first tone in idle state reset audio sample counter
if (cw_receive_state == RS_IDLE) {
smpl_ctr = 0;
memset(rx_rep_buf, 0, sizeof(rx_rep_buf));
cw_rr_current = 0;
cw_ptr = 0;
}
// save the timestamp
cw_rr_start_timestamp = smpl_ctr;
// Set state to indicate we are inside a tone.
old_cw_receive_state = cw_receive_state;
cw_receive_state = RS_IN_TONE;
return CW_ERROR;
break;
case CW_KEYUP_EVENT:
// The receive state is expected to be inside a tone.
if (cw_receive_state != RS_IN_TONE)
return CW_ERROR;
// Save the current timestamp
cw_rr_end_timestamp = smpl_ctr;
element_usec = usec_diff(cw_rr_start_timestamp, cw_rr_end_timestamp);
// make sure our timing values are up to date
sync_parameters();
// If the tone length is shorter than any noise cancelling
// threshold that has been set, then ignore this tone.
if (cw_noise_spike_threshold > 0
&& element_usec < cw_noise_spike_threshold) {
cw_receive_state = RS_IDLE;
return CW_ERROR;
}
// Set up to track speed on dot-dash or dash-dot pairs for this test to work, we need a dot dash pair or a
// dash dot pair to validate timing from and force the speed tracking in the right direction. This method
// is fundamentally different than the method in the unix cw project. Great ideas come from staring at the
// screen long enough!. Its kind of simple really ... when you have no idea how fast or slow the cw is...
// the only way to get a threshold is by having both code elements and setting the threshold between them
// knowing that one is supposed to be 3 times longer than the other. with straight key code... this gets
// quite variable, but with most faster cw sent with electronic keyers, this is one relationship that is
// quite reliable. Lawrence Glaister (ve7it@shaw.ca)
if (last_element > 0) {
// check for dot dash sequence (current should be 3 x last)
if ((element_usec > 2 * last_element) &&
(element_usec < 4 * last_element)) {
update_tracking(last_element, element_usec);
}
// check for dash dot sequence (last should be 3 x current)
if ((last_element > 2 * element_usec) &&
(last_element < 4 * element_usec)) {
update_tracking(element_usec, last_element);
}
}
last_element = element_usec;
// ok... do we have a dit or a dah?
// a dot is anything shorter than 2 dot times
if (element_usec <= cw_adaptive_receive_threshold) {
rx_rep_buf[cw_rr_current++] = CW_DOT_REPRESENTATION;
// printf("%d dit ", last_element/1000); // print dot length
cw_buffer[cw_ptr++] = (float)last_element;
} else {
// a dash is anything longer than 2 dot times
rx_rep_buf[cw_rr_current++] = CW_DASH_REPRESENTATION;
cw_buffer[cw_ptr++] = (float)last_element;
}
// We just added a representation to the receive buffer.
// If it's full, then reset everything as it probably noise
if (cw_rr_current == RECEIVE_CAPACITY - 1) {
cw_receive_state = RS_IDLE;
cw_rr_current = 0; // reset decoding pointer
cw_ptr = 0;
smpl_ctr = 0; // reset audio sample counter
return CW_ERROR;
} else {
// zero terminate representation
rx_rep_buf[cw_rr_current] = 0;
cw_buffer[cw_ptr] = 0.0;
}
// All is well. Move to the more normal after-tone state.
cw_receive_state = RS_AFTER_TONE;
return CW_ERROR;
break;
case CW_QUERY_EVENT:
// this should be called quite often (faster than inter-character gap) It looks after timing
// key up intervals and determining when a character, a word space, or an error char '*' should be returned.
// CW_SUCCESS is returned when there is a printable character. Nothing to do if we are in a tone
if (cw_receive_state == RS_IN_TONE)
return CW_ERROR;
// in this call we expect a pointer to a char to be valid
if (c == NULL) {
// else we had no place to put character...
cw_receive_state = RS_IDLE;
cw_rr_current = 0;
cw_ptr = 0;
// reset decoding pointer
return CW_ERROR;
}
// compute length of silence so far
sync_parameters();
element_usec = usec_diff(cw_rr_end_timestamp, smpl_ctr);
// SHORT time since keyup... nothing to do yet
if (element_usec < (2 * cw_receive_dot_length))
return CW_ERROR;
// MEDIUM time since keyup... check for character space
// one shot through this code via receive state logic
// FARNSWOTH MOD HERE -->
if (element_usec >= (2 * cw_receive_dot_length) &&
element_usec <= (4 * cw_receive_dot_length) &&
cw_receive_state == RS_AFTER_TONE) {
// Look up the representation
//cout << "CW_QUERY medium time after keyup: " << rx_rep_buf;
*c = morse.rx_lookup(rx_rep_buf);
//cout <<": " << *c <<flush;
if (*c == NULL) {
// invalid decode... let user see error
*c = "*";
}
cw_receive_state = RS_IDLE;
cw_rr_current = 0; // reset decoding pointer
space_sent = false;
cw_ptr = 0;
return CW_SUCCESS;
}
// LONG time since keyup... check for a word space
// FARNSWOTH MOD HERE -->
if ((element_usec > (4 * cw_receive_dot_length)) && !space_sent) {
*c = " ";
space_sent = true;
return CW_SUCCESS;
}
// should never get here... catch all
return CW_ERROR;
break;
}
// should never get here... catch all
return CW_ERROR;
}
//===========================================================================
// cw transmit routines
// Define the amplitude envelop for key down events (32 samples long)
// this is 1/2 cycle of a raised cosine
//===========================================================================
double keyshape[KNUM];
void cw::makeshape()
{
for (int i = 0; i < KNUM; i++) keyshape[i] = 1.0;
switch (QSKshape) {
case 1: // blackman
knum = (int)(8 * risetime);
if (knum >= symbollen) knum = symbollen;
for (int i = 0; i < knum; i++)
keyshape[i] = (0.42 - 0.50 * cos(M_PI * i/ knum) + 0.08 * cos(2 * M_PI * i / knum));
break;
case 0: // hanning
default:
knum = (int)(8 * risetime);
if (knum >= symbollen) knum = symbollen;
for (int i = 0; i < knum; i++)
keyshape[i] = 0.5 * (1.0 - cos (M_PI * i / knum));
}
}
inline double cw::nco(double freq)
{
phaseacc += 2.0 * M_PI * freq / samplerate;
if (phaseacc > TWOPI) phaseacc -= TWOPI;
return sin(phaseacc);
}
inline double cw::qsknco()
{
qskphase += 2.0 * M_PI * 1000 / samplerate;
if (qskphase > TWOPI) qskphase -= TWOPI;
return sin(qskphase);
}
//=====================================================================
// send_symbol()
// Sends a part of a morse character (one dot duration) of either
// sound at the correct freq or silence. Rise and fall time is controlled
// with a raised cosine shape.
//
// Left channel contains the shaped A2 CW waveform
// Right channel contains a square wave burst of 1600 Hz that is used
// to trigger a qsk switch. Right channel has pre and post timings for
// proper switching of the qsk switch before and after the A2 element.
// If the Pre + Post timing exceeds the interelement spacing then the
// Pre and / or Post is only applied at the beginning and end of the
// character.
//=======================================================================
//void appendfile(double *left, double *right, size_t count)
//{
// FILE *ofile = fopen("stereo.txt", "a");
// for (size_t i = 0; i < count; i++)
// fprintf(ofile,"%f,%f\n", left[i], right[i]);
// fclose(ofile);
//}
void cw::nb_filter(double *output, double *qsk, int len)
{
// fft implementation of
if (nbfreq != tx_frequency ||
nbpf != progdefaults.CW_bpf) {
nbfreq = tx_frequency;
nbpf = progdefaults.CW_bpf;
lwr = nbfreq - nbpf/2.0;
upr = nbfreq + nbpf/2.0;
if (lwr < 50.0) lwr = 50.0;
if (upr > 3900.0) upr = 3900.0;
lwr /= samplerate;
upr /= samplerate;
cw_xmt_filter->create_filter(lwr, upr);
}
cmplx *zp;
int n = 0;
for (int i = 0; i < len; i++) {
// n will be either 0 or XMT_FILT_LEN
qsk_signal[qsk_ptr] = qsk[i];
qsk_ptr++;
if (qsk_ptr == QSK_DELAY_LEN) qsk_ptr--;
if ((n = cw_xmt_filter->run(
cmplx(output[i], output[i]),
&zp)) > 0) {
for (int k = 0; k < n; k++)
if (abs(zp[k].real()) > maxval) maxval = abs(zp[k].real());
if (maxval == 0) maxval = 1.0;
for (int k = 0; k < n; k++)
xmt_signal[k] = 0.95 * zp[k].real() / maxval;
// appendfile(xmt_signal, qsk_signal, n);
if (progdefaults.QSK)
ModulateStereo(xmt_signal, qsk_signal, n);
else
ModulateXmtr(xmt_signal, n);
for (int k = 0; k < QSK_DELAY_LEN - n - 1; k++)
qsk_signal[k] = qsk_signal[k + n];
qsk_ptr -= n;
}
}
}
int q_carryover = 0, carryover = 0;
void cw::send_symbol(int bits, int len)
{
double freq;
int sample, qsample, i;
int delta = 0;
int keydown;
int keyup;
int kpre;
int kpost;
int duration = 0;
int symlen = 0;
float dsymlen = 0.0;
int currsym = bits & 1;
double qsk_amp = progdefaults.QSK ? 1.0 : 0.0;
sync_transmit_parameters();
acc_symbols += len;
acc_symbols += len;
freq = get_txfreq_woffset();
delta = (int) (len * (progdefaults.CWweight - 50) / 100.0);
symlen = len;
if (currsym == 1) {
dsymlen = len * (progdefaults.CWdash2dot - 3.0) / (progdefaults.CWdash2dot + 1.0);
if (lastsym == 1 && currsym == 1)
symlen += (int)(3 * dsymlen);
else
symlen -= (int)dsymlen;
}
if (delta < -(symlen - knum)) delta = -(symlen - knum);
if (delta > (symlen - knum)) delta = symlen - knum;
keydown = symlen + delta ;
keyup = symlen - delta;
kpre = (int)(progdefaults.CWpre * 8);
if (kpre > symlen) kpre = symlen;
if (progdefaults.QSK) {
kpre = (int)(progdefaults.CWpre * 8);
if (kpre > symlen) kpre = symlen;
if (progdefaults.CWnarrow) {
if (keydown - 2*knum < 0)
kpost = knum + (int)(progdefaults.CWpost * 8);
else
kpost = keydown - knum + (int)(progdefaults.CWpost * 8);
} else
kpost = keydown + (int)(progdefaults.CWpost * 8);
if (kpost < 0) kpost = 0;
} else {
kpre = 0;
kpost = 0;
}
if (firstelement) {
firstelement = false;
return;
}
if (currsym == 1) { // keydown
sample = 0;
if (lastsym == 1) {
for (i = 0; i < keydown; i++, sample++) {
outbuf[sample] = nco(freq);
qskbuf[sample] = qsk_amp * qsknco();
}
duration = keydown;
} else {
if (carryover) {
for (int i = carryover; i < knum; i++, sample++)
outbuf[sample] = nco(freq) * keyshape[knum - i];
while (sample < kpre)
outbuf[sample++] = 0 * nco(freq);
} else
for (int i = 0; i < kpre; i++, sample++)
outbuf[sample] = 0 * nco(freq);
sample = 0;
for (int i = 0; i < kpre; i++, sample++) {
qskbuf[sample] = qsk_amp * qsknco();
}
for (int i = 0; i < knum; i++, sample++) {
outbuf[sample] = nco(freq) * keyshape[i];
qskbuf[sample] = qsk_amp * qsknco();
}
duration = kpre + knum;
}
carryover = 0;
}
else { // keyup
if (lastsym == 0) {
duration = keyup;
sample = 0;
if (carryover) {
for (int i = carryover; i < knum; i++, sample++)
outbuf[sample] = nco(freq) * keyshape[knum - i];
while (sample < duration)
outbuf[sample++] = 0 * nco(freq);
} else
while (sample < duration)
outbuf[sample++] = 0 * nco(freq);
carryover = 0;
qsample = 0;
if (q_carryover) {
for (int i = 0; i < q_carryover; i++, qsample++) {
qskbuf[qsample] = qsk_amp * qsknco();
}
while (qsample < duration)
qskbuf[qsample++] = 0 * qsknco();
} else
while (qsample < duration)
qskbuf[qsample++] = 0 * qsknco();
if (q_carryover > duration)
q_carryover = duration - q_carryover;
else
q_carryover = 0;
} else { // last symbol = 1
duration = 2 * len - kpre - knum;
carryover = 0;
sample = 0;
int next = keydown - knum;
if (progdefaults.CWnarrow)
next = keydown - 2*knum;
for (int i = 0; i < next; i++, sample++)
outbuf[sample] = nco(freq);
for (int i = 0; i < knum; i++, sample++) {
if (sample == duration) {
carryover = i;
break;
}
outbuf[sample] = nco(freq) * keyshape[knum - i];
}
while (sample < duration)
outbuf[sample++] = 0 * nco(freq);
q_carryover = 0;
qsample = 0;
for (int i = 0; i < kpost; i++, qsample++) {
if (qsample == duration) {
q_carryover = kpost - duration;
break;
}
qskbuf[qsample] = qsk_amp * qsknco();
}
while (qsample < duration)
qskbuf[qsample++] = 0 * qsknco();
}
}
if (duration > 0) {
if (progdefaults.CW_bpf_on)
nb_filter(outbuf, qskbuf, duration);
else {
if (progdefaults.QSK)
ModulateStereo(outbuf, qskbuf, duration);
else
ModulateXmtr(outbuf, duration);
}
}
lastsym = currsym;
firstelement = false;
}
//=====================================================================
// send_ch()
// sends a morse character and the space afterwards
//=======================================================================
void cw::send_ch(int ch)
{
int code;
int chout = ch;
int flen;
sync_parameters();
// handle word space separately (7 dots spacing)
// last char already had 3 elements of inter-character spacing
if ((chout == ' ') || (chout == '\n')) {
firstelement = false;
flen = 4 * symbollen;
while (flen - symbollen > 0) {
send_symbol(0, symbollen);
flen -= symbollen;
}
if (flen) send_symbol(0, flen);
put_echo_char(progdefaults.rx_lowercase ? tolower(ch) : ch);
return;
}
// convert character code to a morse representation
if ((chout < 256) && (chout >= 0)) {
code = morse.tx_lookup(chout); //cw_tx_lookup(ch);
firstelement = true;
} else {
code = 0x04; // two extra dot spaces
firstelement = false;
}
// loop sending out binary bits of cw character
// at WPM or Farnsworth rate
if (progdefaults.CWusefarnsworth && (progdefaults.CWspeed <= progdefaults.CWfarnsworth))
flen = fsymlen;
else
flen = symbollen;
int charlen = 0;
while (code > 1) {
send_symbol(code, flen);
charlen++;
code = code >> 1;
}
// inter character space at WPM/FWPM rate
flen = symbollen;
if (progdefaults.CWusefarnsworth && (progdefaults.CWspeed <= progdefaults.CWfarnsworth))
flen += (symbollen - fsymlen)*charlen;
while(flen - symbollen > 0) {
send_symbol(0, symbollen);
flen -= symbollen;
}
if (flen) send_symbol(0, flen);
FL_AWAKE();
if (ch != -1) {
string prtstr = morse.tx_print(ch);
if (prtstr.length() == 1)
put_echo_char(progdefaults.rx_lowercase ? tolower(prtstr[0]) : prtstr[0]);
else
for (size_t n = 0; n < prtstr.length(); n++)
put_echo_char(progdefaults.rx_lowercase ? tolower(prtstr[n]) : prtstr[n], FTextBase::CTRL);
}
}
//=====================================================================
// cw_txprocess()
// Read characters from screen and send them out the sound card.
// This is called repeatedly from a thread during tx.
//=======================================================================
int cw::tx_process()
{
int c;
if (use_paren != progdefaults.CW_use_paren ||
prosigns != progdefaults.CW_prosigns) {
use_paren = progdefaults.CW_use_paren;
prosigns = progdefaults.CW_prosigns;
morse.init();
}
c = get_tx_char();
if (c == GET_TX_CHAR_ETX || stopflag) {
stopflag = false;
if (progdefaults.CW_bpf_on) { // flush the transmit bandpass filter
int n = cw_xmt_filter->flush_size();
for (int i = 0; i < n; i++) outbuf[i] = 0;
nb_filter(outbuf, outbuf, n);
}
return -1;
}
acc_symbols = 0;
send_ch(c);
xmt_samples = char_samples = acc_symbols;
// printf("%5s %d samples, overhead %d, %f sec's\n",
// ascii3[c & 0xff],
// char_samples,
// ovhd_samples,
// 1.0 * char_samples / samplerate);
return 0;
}
void cw::incWPM()
{
if (usedefaultWPM) return;
if (progdefaults.CWspeed < progdefaults.CWupperlimit) {
progdefaults.CWspeed++;
sync_parameters();
set_CWwpm();
update_Status();
}
}
void cw::decWPM()
{
if (usedefaultWPM) return;
if (progdefaults.CWspeed > progdefaults.CWlowerlimit) {
progdefaults.CWspeed--;
set_CWwpm();
sync_parameters();
update_Status();
}
}
void cw::toggleWPM()
{
usedefaultWPM = !usedefaultWPM;
sync_parameters();
update_Status();
}