mirror of
https://github.com/eried/portapack-mayhem.git
synced 2024-12-26 15:59:28 -05:00
289 lines
7.2 KiB
C++
289 lines
7.2 KiB
C++
/*
|
|
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
|
|
* Copyright (C) 2016 Furrtek
|
|
*
|
|
* This file is part of PortaPack.
|
|
*
|
|
* 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; either version 2, 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 for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, Inc., 51 Franklin Street,
|
|
* Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include "pocsag.hpp"
|
|
|
|
#include "baseband_api.hpp"
|
|
#include "portapack.hpp"
|
|
using namespace portapack;
|
|
|
|
#include "string_format.hpp"
|
|
#include "utility.hpp"
|
|
|
|
namespace pocsag {
|
|
|
|
std::string bitrate_str(BitRate bitrate) {
|
|
switch (bitrate) {
|
|
case BitRate::FSK512: return "512bps ";
|
|
case BitRate::FSK1200: return "1200bps";
|
|
case BitRate::FSK2400: return "2400bps";
|
|
default: return "????";
|
|
}
|
|
}
|
|
|
|
std::string flag_str(PacketFlag packetflag) {
|
|
switch (packetflag) {
|
|
case PacketFlag::NORMAL: return "OK";
|
|
case PacketFlag::TIMED_OUT: return "TIMED OUT";
|
|
default: return "";
|
|
}
|
|
}
|
|
|
|
void insert_BCH(BCHCode& BCH_code, uint32_t * codeword) {
|
|
uint32_t parity = 0;
|
|
int data[21];
|
|
int bit;
|
|
int * bb;
|
|
size_t c;
|
|
|
|
for (c = 0; c < 21; c++) {
|
|
bit = (((*codeword) << c) & 0x80000000U) ? 1 : 0;
|
|
if (bit) parity++;
|
|
data[c] = bit;
|
|
}
|
|
|
|
bb = BCH_code.encode(data);
|
|
|
|
// Make sure ECC bits are cleared
|
|
(*codeword) &= 0xFFFFF801;
|
|
|
|
for (c = 0; c < 10; c++) {
|
|
bit = bb[c];
|
|
(*codeword) |= (bit << (10 - c));
|
|
if (bit) parity++;
|
|
}
|
|
|
|
// Even parity
|
|
(*codeword) |= (parity & 1);
|
|
}
|
|
|
|
uint32_t get_digit_code(char code) {
|
|
if ((code >= '0') && (code <= '9')) {
|
|
code -= '0';
|
|
} else {
|
|
if (code == 'S')
|
|
code = 10;
|
|
else if (code == 'U')
|
|
code = 11;
|
|
else if (code == ' ')
|
|
code = 12;
|
|
else if (code == '-')
|
|
code = 13;
|
|
else if (code == ']')
|
|
code = 14;
|
|
else if (code == '[')
|
|
code = 15;
|
|
else
|
|
code = 12;
|
|
}
|
|
|
|
code = ((code & 0x0C) >> 2) | ((code & 0x03) << 2); // ----3210 -> ----1032
|
|
code = ((code & 0x0A) >> 1) | ((code & 0x05) << 1); // ----1032 -> ----0123
|
|
|
|
return code;
|
|
}
|
|
|
|
void pocsag_encode(const MessageType type, BCHCode& BCH_code, const uint32_t function, const std::string message, const uint32_t address,
|
|
std::vector<uint32_t>& codewords) {
|
|
|
|
size_t b, c, address_slot;
|
|
size_t bit_idx, char_idx = 0;
|
|
uint32_t codeword, digit_code;
|
|
char ascii_char = 0;
|
|
|
|
size_t message_size = message.size();
|
|
|
|
// Preamble
|
|
for (b = 0; b < (POCSAG_PREAMBLE_LENGTH / 32); b++) {
|
|
codewords.push_back(0xAAAAAAAA);
|
|
}
|
|
|
|
// Address
|
|
codeword = (address & 0x1FFFF8U) << 10;
|
|
address_slot = (address & 7) * 2;
|
|
// Function
|
|
codeword |= (function << 11);
|
|
|
|
insert_BCH(BCH_code, &codeword);
|
|
|
|
// Address batch
|
|
codewords.push_back(POCSAG_SYNCWORD);
|
|
for (c = 0; c < 16; c++) {
|
|
if (c == address_slot) {
|
|
codewords.push_back(codeword);
|
|
if (type != MessageType::ADDRESS_ONLY) break;
|
|
} else
|
|
codewords.push_back(POCSAG_IDLEWORD);
|
|
}
|
|
|
|
if (type == MessageType::ADDRESS_ONLY) return; // Done.
|
|
|
|
c++;
|
|
codeword = 0;
|
|
bit_idx = 20 + 11;
|
|
|
|
// Messages batch(es)
|
|
do {
|
|
if (c == 0) codewords.push_back(POCSAG_SYNCWORD);
|
|
|
|
for ( ; c < 16; c++) {
|
|
|
|
// Fill up 20 bits
|
|
if (type == MessageType::ALPHANUMERIC) {
|
|
if ((char_idx < message_size) || (ascii_char)) {
|
|
do {
|
|
bit_idx -= 7;
|
|
|
|
if (char_idx < message_size)
|
|
ascii_char = message[char_idx] & 0x7F;
|
|
else
|
|
ascii_char = 0; // Codeword padding
|
|
|
|
// Bottom's up
|
|
ascii_char = (ascii_char & 0xF0) >> 4 | (ascii_char & 0x0F) << 4; // *6543210 -> 3210*654
|
|
ascii_char = (ascii_char & 0xCC) >> 2 | (ascii_char & 0x33) << 2; // 3210*654 -> 103254*6
|
|
ascii_char = (ascii_char & 0xAA) >> 2 | (ascii_char & 0x55); // 103254*6 -> *0123456
|
|
|
|
codeword |= (ascii_char << bit_idx);
|
|
|
|
char_idx++;
|
|
|
|
} while (bit_idx > 11);
|
|
|
|
codeword &= 0x7FFFF800; // Trim data
|
|
codeword |= 0x80000000; // Message type
|
|
insert_BCH(BCH_code, &codeword);
|
|
|
|
codewords.push_back(codeword);
|
|
|
|
if (bit_idx != 11) {
|
|
bit_idx = 20 + bit_idx;
|
|
codeword = ascii_char << bit_idx;
|
|
} else {
|
|
bit_idx = 20 + 11;
|
|
codeword = 0;
|
|
}
|
|
} else {
|
|
codewords.push_back(POCSAG_IDLEWORD); // Batch padding
|
|
}
|
|
} else if (type == MessageType::NUMERIC_ONLY) {
|
|
if (char_idx < message_size) {
|
|
do {
|
|
bit_idx -= 4;
|
|
|
|
if (char_idx < message_size)
|
|
digit_code = get_digit_code(message[char_idx]);
|
|
else
|
|
digit_code = 3; // Space (codeword padding)
|
|
|
|
codeword |= (digit_code << bit_idx);
|
|
|
|
char_idx++;
|
|
|
|
} while (bit_idx > 11);
|
|
|
|
codeword |= 0x80000000; // Message type
|
|
insert_BCH(BCH_code, &codeword);
|
|
|
|
codewords.push_back(codeword);
|
|
|
|
bit_idx = 20 + 11;
|
|
codeword = 0;
|
|
} else {
|
|
codewords.push_back(POCSAG_IDLEWORD); // Batch padding
|
|
}
|
|
}
|
|
}
|
|
|
|
c = 0;
|
|
|
|
} while (char_idx < message_size);
|
|
}
|
|
|
|
void pocsag_decode_batch(const POCSAGPacket& batch, POCSAGState * const state) {
|
|
uint32_t codeword;
|
|
char ascii_char;
|
|
std::string output_text = "";
|
|
|
|
state->out_type = EMPTY;
|
|
|
|
// For each codeword...
|
|
for (size_t i = 0; i < 16; i++) {
|
|
codeword = batch[i];
|
|
|
|
if (!(codeword & 0x80000000U)) {
|
|
// Address codeword
|
|
if (state->mode == STATE_CLEAR) {
|
|
if (codeword != POCSAG_IDLEWORD) {
|
|
state->function = (codeword >> 11) & 3;
|
|
state->address = (codeword >> 10) & 0x1FFFF8U; // 18 MSBs are transmitted
|
|
state->mode = STATE_HAVE_ADDRESS;
|
|
state->out_type = ADDRESS;
|
|
|
|
state->ascii_idx = 0;
|
|
state->ascii_data = 0;
|
|
}
|
|
} else {
|
|
state->mode = STATE_CLEAR; // New address = new message
|
|
}
|
|
} else {
|
|
// Message codeword
|
|
if (state->mode == STATE_HAVE_ADDRESS) {
|
|
// First message codeword: complete address
|
|
state->address |= (i >> 1); // Add in the 3 LSBs (frame #)
|
|
state->mode = STATE_GETTING_MSG;
|
|
}
|
|
|
|
state->out_type = MESSAGE;
|
|
|
|
state->ascii_data |= ((codeword >> 11) & 0xFFFFF); // Get 20 message bits
|
|
state->ascii_idx += 20;
|
|
|
|
// Raw 20 bits to 7 bit reversed ASCII
|
|
while (state->ascii_idx >= 7) {
|
|
state->ascii_idx -= 7;
|
|
ascii_char = ((state->ascii_data) >> (state->ascii_idx)) & 0x7F;
|
|
|
|
// Bottom's up
|
|
ascii_char = (ascii_char & 0xF0) >> 4 | (ascii_char & 0x0F) << 4; // 01234567 -> 45670123
|
|
ascii_char = (ascii_char & 0xCC) >> 2 | (ascii_char & 0x33) << 2; // 45670123 -> 67452301
|
|
ascii_char = (ascii_char & 0xAA) >> 2 | (ascii_char & 0x55); // 67452301 -> *7654321
|
|
|
|
// Translate non-printable chars
|
|
if ((ascii_char < 32) || (ascii_char > 126))
|
|
output_text += "[" + to_string_dec_uint(ascii_char) + "]";
|
|
else
|
|
output_text += ascii_char;
|
|
}
|
|
|
|
state->ascii_data <<= 20; // Remaining bits are for next time...
|
|
}
|
|
}
|
|
|
|
state->output = output_text;
|
|
|
|
if (state->mode == STATE_HAVE_ADDRESS)
|
|
state->mode = STATE_CLEAR;
|
|
}
|
|
|
|
} /* namespace pocsag */
|