mirror of
https://github.com/f4exb/sdrangel.git
synced 2024-12-23 10:05:46 -05:00
149 lines
4.0 KiB
C++
149 lines
4.0 KiB
C++
///////////////////////////////////////////////////////////////////////////////////
|
|
// Copyright (C) 2022 Edouard Griffiths, F4EXB <f4exb06@gmail.com> //
|
|
// //
|
|
// This program 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 as version 3 of the License, or //
|
|
// (at your option) any later version. //
|
|
// //
|
|
// This program 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 V3 for more details. //
|
|
// //
|
|
// You should have received a copy of the GNU General Public License //
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>. //
|
|
///////////////////////////////////////////////////////////////////////////////////
|
|
|
|
#include <QString>
|
|
#include <array>
|
|
#include "util/crc.h"
|
|
#include "m17modax25.h"
|
|
|
|
M17ModAX25::M17ModAX25() :
|
|
m_ax25Control(3),
|
|
m_ax25PID(AX25_NO_L3)
|
|
{}
|
|
|
|
M17ModAX25::~M17ModAX25()
|
|
{}
|
|
|
|
QByteArray M17ModAX25::makePacket(const QString& callsign, const QString& to, const QString& via, const QString& data)
|
|
{
|
|
std::array<uint8_t, AX25_MAX_BYTES> packet;
|
|
uint8_t *crc_start;
|
|
uint8_t *p;
|
|
crc16x25 crc;
|
|
uint16_t crcValue;
|
|
int len;
|
|
int packet_length;
|
|
|
|
// Create AX.25 packet
|
|
p = packet.data();
|
|
// Unique preamble flag
|
|
// *p++ = AX25_FLAG;
|
|
crc_start = p;
|
|
// Dest
|
|
p = ax25_address(p, to, 0xe0);
|
|
// From
|
|
p = ax25_address(p, callsign, 0x60);
|
|
// Via
|
|
p = ax25_address(p, via, 0x61);
|
|
// Control
|
|
*p++ = m_ax25Control;
|
|
// PID
|
|
*p++ = m_ax25PID;
|
|
// Data
|
|
len = data.length();
|
|
memcpy(p, data.toUtf8(), len);
|
|
p += len;
|
|
// CRC (do not include flags)
|
|
crc.calculate(crc_start, p-crc_start);
|
|
crcValue = crc.get();
|
|
*p++ = crcValue & 0xff;
|
|
*p++ = (crcValue >> 8);
|
|
// Unique postamble flag
|
|
// *p++ = AX25_FLAG;
|
|
|
|
packet_length = p-&packet[0];
|
|
|
|
return QByteArray(reinterpret_cast<const char*>(packet.data()), packet_length);
|
|
}
|
|
|
|
uint8_t *M17ModAX25::ax25_address(uint8_t *p, QString address, uint8_t crrl)
|
|
{
|
|
int len;
|
|
int i;
|
|
QByteArray b;
|
|
uint8_t ssid = 0;
|
|
bool hyphenSeen = false;
|
|
|
|
len = address.length();
|
|
b = address.toUtf8();
|
|
ssid = 0;
|
|
|
|
for (i = 0; i < 6; i++)
|
|
{
|
|
if ((i < len) && !hyphenSeen)
|
|
{
|
|
if (b[i] == '-')
|
|
{
|
|
ax25_ssid(b, i, len, ssid);
|
|
hyphenSeen = true;
|
|
*p++ = ' ' << 1;
|
|
}
|
|
else
|
|
{
|
|
*p++ = b[i] << 1;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
*p++ = ' ' << 1;
|
|
}
|
|
}
|
|
|
|
if (b[i] == '-') {
|
|
ax25_ssid(b, i, len, ssid);
|
|
}
|
|
|
|
*p++ = crrl | (ssid << 1);
|
|
|
|
return p;
|
|
}
|
|
|
|
bool M17ModAX25::ax25_ssid(QByteArray& b, int i, int len, uint8_t& ssid)
|
|
{
|
|
if (b[i] == '-')
|
|
{
|
|
if (len > i + 1)
|
|
{
|
|
ssid = b[i+1] - '0';
|
|
|
|
if ((len > i + 2) && isdigit(b[i+2])) {
|
|
ssid = (ssid*10) + (b[i+2] - '0');
|
|
}
|
|
|
|
if (ssid >= 16)
|
|
{
|
|
qDebug("M17ModAX25::ax25_ssid: ax25_address: SSID greater than 15 not supported");
|
|
ssid = ssid & 0xf;
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
return true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
qDebug("M17ModAX25::ax25_ssid: ax25_address: SSID number missing");
|
|
return false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|