diff --git a/examples/r2t2/arduino-tx/arduino-tx.ino b/examples/r2t2/arduino-tx/arduino-tx.ino index 14cf5c4..3df3f9a 100644 --- a/examples/r2t2/arduino-tx/arduino-tx.ino +++ b/examples/r2t2/arduino-tx/arduino-tx.ino @@ -1,52 +1,29 @@ -#define kPinLed 13 -#define kPinSpeaker 11 +#include "ggwave.h" + +#define kPinLed0 13 +#define kPinSpeaker 10 void setup() { - pinMode(kPinLed, OUTPUT); + pinMode(kPinLed0, OUTPUT); pinMode(kPinSpeaker, OUTPUT); - - randomSeed(analogRead(0)); } +char txt[64]; // used for printf + void loop() { - if (1) { - tone(kPinSpeaker, 1125.00); delay( 64); - tone(kPinSpeaker, 937.50); delay( 64); - tone(kPinSpeaker, 984.38); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 1312.50); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 1312.50); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 1453.12); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 750.00); delay( 64); - tone(kPinSpeaker, 843.75); delay( 64); - tone(kPinSpeaker, 937.50); delay( 64); - tone(kPinSpeaker, 984.38); delay( 64); - tone(kPinSpeaker, 1078.12); delay( 128); - tone(kPinSpeaker, 1171.88); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 937.50); delay( 64); - tone(kPinSpeaker, 1078.12); delay( 64); - tone(kPinSpeaker, 937.50); delay( 64); - tone(kPinSpeaker, 1078.12); delay( 64); - tone(kPinSpeaker, 984.38); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 843.75); delay( 64); - tone(kPinSpeaker, 1078.12); delay( 64); - tone(kPinSpeaker, 796.88); delay( 64); - tone(kPinSpeaker, 843.75); delay( 64); - tone(kPinSpeaker, 796.88); delay( 64); - tone(kPinSpeaker, 1453.12); delay( 64); - tone(kPinSpeaker, 796.88); delay( 64); - tone(kPinSpeaker, 1171.88); delay( 64); - tone(kPinSpeaker, 1125.00); delay( 64); - tone(kPinSpeaker, 1265.62); delay( 64); - tone(kPinSpeaker, 1031.25); delay( 64); - tone(kPinSpeaker, 1312.50); delay( 64); - } + char tx[16]; + memset(tx, 0, sizeof(tx)); + strcpy(tx, "Hello World!"); - noTone(kPinSpeaker); - delay(3000); + digitalWrite(kPinLed0, HIGH); + GGWave::send(kPinSpeaker, tx, GGWave::TX_ARDUINO_512_FASTEST); + digitalWrite(kPinLed0, LOW); + + delay(250); + + digitalWrite(kPinLed0, HIGH); + GGWave::send(kPinSpeaker, "This is GGWave!!", GGWave::TX_ARDUINO_512_FASTEST); + digitalWrite(kPinLed0, LOW); + + delay(5000); } diff --git a/examples/r2t2/arduino-tx/ggwave.h b/examples/r2t2/arduino-tx/ggwave.h new file mode 100644 index 0000000..2c433ec --- /dev/null +++ b/examples/r2t2/arduino-tx/ggwave.h @@ -0,0 +1,937 @@ +#pragma once + +// +// The code in the RS namespace provides Reed-Solomon based error correction. +// The code is taken from https://github.com/mersinvald/Reed-Solomon. +// The LICENSE of the code is copied below: +// +// Copyright © 2015 Mike Lubinets, github.com/mersinvald +// +// Permission is hereby granted, free of charge, to any person +// obtaining a copy of this software and associated documentation files +// (the “Software”), to deal in the Software without restriction, +// including without limitation the rights to use, copy, modify, merge, +// publish, distribute, sublicense, and/or sell copies of the Software, +// and to permit persons to whom the Software is furnished to do so, +// subject to the following conditions: +// +// The above copyright notice and this permission notice shall be +// included in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, +// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS +// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +// SOFTWARE. +// +// The GGWave implementation is in the GGWave namespace at the bottom of this file. +// + +#include + +namespace RS { + +struct Poly { + Poly() + : length(0), _memory(NULL) {} + + Poly(uint8_t id, uint16_t offset, uint8_t size) \ + : length(0), _id(id), _size(size), _offset(offset), _memory(NULL) {} + + /* @brief Append number at the end of polynomial + * @param num - number to append + * @return false if polynomial can't be stretched */ + inline bool Append(uint8_t num) { + assert(length < _size); + ptr()[length++] = num; + return true; + } + + /* @brief Polynomial initialization */ + inline void Init(uint8_t id, uint16_t offset, uint8_t size, uint8_t** memory_ptr) { + this->_id = id; + this->_offset = offset; + this->_size = size; + this->length = 0; + this->_memory = memory_ptr; + } + + /* @brief Polynomial memory zeroing */ + inline void Reset() { + memset((void*)ptr(), 0, this->_size); + } + + /* @brief Copy polynomial to memory + * @param src - source byte-sequence + * @param size - size of polynomial + * @param offset - write offset */ + inline void Set(const uint8_t* src, uint8_t len, uint8_t offset = 0) { + assert(src && len <= this->_size-offset); + memcpy(ptr()+offset, src, len * sizeof(uint8_t)); + length = len + offset; + } + +#define poly_max(a, b) ((a > b) ? (a) : (b)) + + inline void Copy(const Poly* src) { + length = poly_max(length, src->length); + Set(src->ptr(), length); + } + + inline uint8_t& at(uint8_t i) const { + assert(i < _size); + return ptr()[i]; + } + + inline uint8_t id() const { + return _id; + } + + inline uint8_t size() const { + return _size; + } + + // Returns pointer to memory of this polynomial + inline uint8_t* ptr() const { + assert(_memory && *_memory); + return (*_memory) + _offset; + } + + uint8_t length; + +protected: + + uint8_t _id; + uint8_t _size; // Size of reserved memory for this polynomial + uint16_t _offset; // Offset in memory + uint8_t** _memory; // Pointer to pointer to memory +}; + +namespace gf { + + +/* GF tables pre-calculated for 0x11d primitive polynomial */ + +const uint8_t exp[512] PROGMEM = { + 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26, 0x4c, + 0x98, 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x3, 0x6, 0xc, 0x18, 0x30, 0x60, 0xc0, 0x9d, + 0x27, 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23, 0x46, + 0x8c, 0x5, 0xa, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1, 0x5f, + 0xbe, 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0xf, 0x1e, 0x3c, 0x78, 0xf0, 0xfd, + 0xe7, 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2, 0xd9, + 0xaf, 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0xd, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce, 0x81, + 0x1f, 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc, 0x85, + 0x17, 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54, 0xa8, + 0x4d, 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73, 0xe6, + 0xd1, 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff, 0xe3, + 0xdb, 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41, 0x82, + 0x19, 0x32, 0x64, 0xc8, 0x8d, 0x7, 0xe, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6, 0x51, + 0xa2, 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x9, 0x12, + 0x24, 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0xb, 0x16, 0x2c, + 0x58, 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x1, 0x2, + 0x4, 0x8, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26, 0x4c, 0x98, + 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x3, 0x6, 0xc, 0x18, 0x30, 0x60, 0xc0, 0x9d, 0x27, + 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23, 0x46, 0x8c, + 0x5, 0xa, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1, 0x5f, 0xbe, + 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0xf, 0x1e, 0x3c, 0x78, 0xf0, 0xfd, 0xe7, + 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2, 0xd9, 0xaf, + 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0xd, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce, 0x81, 0x1f, + 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc, 0x85, 0x17, + 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54, 0xa8, 0x4d, + 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73, 0xe6, 0xd1, + 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff, 0xe3, 0xdb, + 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41, 0x82, 0x19, + 0x32, 0x64, 0xc8, 0x8d, 0x7, 0xe, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6, 0x51, 0xa2, + 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x9, 0x12, 0x24, + 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0xb, 0x16, 0x2c, 0x58, + 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x1, 0x2 +}; + +const uint8_t log[256] PROGMEM = { + 0x0, 0x0, 0x1, 0x19, 0x2, 0x32, 0x1a, 0xc6, 0x3, 0xdf, 0x33, 0xee, 0x1b, 0x68, 0xc7, 0x4b, 0x4, + 0x64, 0xe0, 0xe, 0x34, 0x8d, 0xef, 0x81, 0x1c, 0xc1, 0x69, 0xf8, 0xc8, 0x8, 0x4c, 0x71, 0x5, + 0x8a, 0x65, 0x2f, 0xe1, 0x24, 0xf, 0x21, 0x35, 0x93, 0x8e, 0xda, 0xf0, 0x12, 0x82, 0x45, 0x1d, + 0xb5, 0xc2, 0x7d, 0x6a, 0x27, 0xf9, 0xb9, 0xc9, 0x9a, 0x9, 0x78, 0x4d, 0xe4, 0x72, 0xa6, 0x6, + 0xbf, 0x8b, 0x62, 0x66, 0xdd, 0x30, 0xfd, 0xe2, 0x98, 0x25, 0xb3, 0x10, 0x91, 0x22, 0x88, 0x36, + 0xd0, 0x94, 0xce, 0x8f, 0x96, 0xdb, 0xbd, 0xf1, 0xd2, 0x13, 0x5c, 0x83, 0x38, 0x46, 0x40, 0x1e, + 0x42, 0xb6, 0xa3, 0xc3, 0x48, 0x7e, 0x6e, 0x6b, 0x3a, 0x28, 0x54, 0xfa, 0x85, 0xba, 0x3d, 0xca, + 0x5e, 0x9b, 0x9f, 0xa, 0x15, 0x79, 0x2b, 0x4e, 0xd4, 0xe5, 0xac, 0x73, 0xf3, 0xa7, 0x57, 0x7, + 0x70, 0xc0, 0xf7, 0x8c, 0x80, 0x63, 0xd, 0x67, 0x4a, 0xde, 0xed, 0x31, 0xc5, 0xfe, 0x18, 0xe3, + 0xa5, 0x99, 0x77, 0x26, 0xb8, 0xb4, 0x7c, 0x11, 0x44, 0x92, 0xd9, 0x23, 0x20, 0x89, 0x2e, 0x37, + 0x3f, 0xd1, 0x5b, 0x95, 0xbc, 0xcf, 0xcd, 0x90, 0x87, 0x97, 0xb2, 0xdc, 0xfc, 0xbe, 0x61, 0xf2, + 0x56, 0xd3, 0xab, 0x14, 0x2a, 0x5d, 0x9e, 0x84, 0x3c, 0x39, 0x53, 0x47, 0x6d, 0x41, 0xa2, 0x1f, + 0x2d, 0x43, 0xd8, 0xb7, 0x7b, 0xa4, 0x76, 0xc4, 0x17, 0x49, 0xec, 0x7f, 0xc, 0x6f, 0xf6, 0x6c, + 0xa1, 0x3b, 0x52, 0x29, 0x9d, 0x55, 0xaa, 0xfb, 0x60, 0x86, 0xb1, 0xbb, 0xcc, 0x3e, 0x5a, 0xcb, + 0x59, 0x5f, 0xb0, 0x9c, 0xa9, 0xa0, 0x51, 0xb, 0xf5, 0x16, 0xeb, 0x7a, 0x75, 0x2c, 0xd7, 0x4f, + 0xae, 0xd5, 0xe9, 0xe6, 0xe7, 0xad, 0xe8, 0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf +}; + + + +/* ################################ + * # OPERATIONS OVER GALUA FIELDS # + * ################################ */ + +/* @brief Addition in Galua Fields + * @param x - left operand + * @param y - right operand + * @return x + y */ +inline uint8_t add(uint8_t x, uint8_t y) { + return x^y; +} + +/* ##### GF substraction ###### */ +/* @brief Substraction in Galua Fields + * @param x - left operand + * @param y - right operand + * @return x - y */ +inline uint8_t sub(uint8_t x, uint8_t y) { + return x^y; +} + +/* @brief Multiplication in Galua Fields + * @param x - left operand + * @param y - rifht operand + * @return x * y */ +inline uint8_t mul(uint16_t x, uint16_t y){ + if (x == 0 || y == 0) + return 0; + return pgm_read_byte(exp + pgm_read_byte(log + x) + pgm_read_byte(log + y)); +} + +/* @brief Division in Galua Fields + * @param x - dividend + * @param y - divisor + * @return x / y */ +inline uint8_t div(uint8_t x, uint8_t y){ + assert(y != 0); + if(x == 0) return 0; + return pgm_read_byte(exp + (pgm_read_byte(log + x) + 255 - pgm_read_byte(log + y)) % 255); +} + +/* @brief X in power Y w + * @param x - operand + * @param power - power + * @return x^power */ +inline uint8_t pow(uint8_t x, intmax_t power){ + intmax_t i = pgm_read_byte(log + x); + i *= power; + i %= 255; + if(i < 0) i = i + 255; + return pgm_read_byte(exp + i); +} + +/* @brief Inversion in Galua Fields + * @param x - number + * @return inversion of x */ +inline uint8_t inverse(uint8_t x){ + return pgm_read_byte(exp + 255 - pgm_read_byte(log + x)); /* == div(1, x); */ +} + +/* ########################## + * # POLYNOMIALS OPERATIONS # + * ########################## */ + +/* @brief Multiplication polynomial by scalar + * @param &p - source polynomial + * @param &newp - destination polynomial + * @param x - scalar */ +inline void +poly_scale(const Poly *p, Poly *newp, uint16_t x) { + newp->length = p->length; + for(uint16_t i = 0; i < p->length; i++){ + newp->at(i) = mul(p->at(i), x); + } +} + +/* @brief Addition of two polynomials + * @param &p - right operand polynomial + * @param &q - left operand polynomial + * @param &newp - destination polynomial */ +inline void +poly_add(const Poly *p, const Poly *q, Poly *newp) { + newp->length = poly_max(p->length, q->length); + memset(newp->ptr(), 0, newp->length * sizeof(uint8_t)); + + for(uint8_t i = 0; i < p->length; i++){ + newp->at(i + newp->length - p->length) = p->at(i); + } + + for(uint8_t i = 0; i < q->length; i++){ + newp->at(i + newp->length - q->length) ^= q->at(i); + } +} + + +/* @brief Multiplication of two polynomials + * @param &p - right operand polynomial + * @param &q - left operand polynomial + * @param &newp - destination polynomial */ +inline void +poly_mul(const Poly *p, const Poly *q, Poly *newp) { + newp->length = p->length + q->length - 1; + memset(newp->ptr(), 0, newp->length * sizeof(uint8_t)); + /* Compute the polynomial multiplication (just like the outer product of two vectors, + * we multiply each coefficients of p with all coefficients of q) */ + for(uint8_t j = 0; j < q->length; j++){ + for(uint8_t i = 0; i < p->length; i++){ + newp->at(i+j) ^= mul(p->at(i), q->at(j)); /* == r[i + j] = gf_add(r[i+j], gf_mul(p[i], q[j])) */ + } + } +} + +/* @brief Division of two polynomials + * @param &p - right operand polynomial + * @param &q - left operand polynomial + * @param &newp - destination polynomial */ +inline void +poly_div(const Poly *p, const Poly *q, Poly *newp) { + if(p->ptr() != newp->ptr()) { + memcpy(newp->ptr(), p->ptr(), p->length*sizeof(uint8_t)); + } + + newp->length = p->length; + + uint8_t coef; + + for(int i = 0; i < (p->length-(q->length-1)); i++){ + coef = newp->at(i); + if(coef != 0){ + for(uint8_t j = 1; j < q->length; j++){ + if(q->at(j) != 0) + newp->at(i+j) ^= mul(q->at(j), coef); + } + } + } + + size_t sep = p->length-(q->length-1); + memmove(newp->ptr(), newp->ptr()+sep, (newp->length-sep) * sizeof(uint8_t)); + newp->length = newp->length-sep; +} + +/* @brief Evaluation of polynomial in x + * @param &p - polynomial to evaluate + * @param x - evaluation point */ +inline int8_t +poly_eval(const Poly *p, uint16_t x) { + uint8_t y = p->at(0); + for(uint8_t i = 1; i < p->length; i++){ + y = mul(y, x) ^ p->at(i); + } + return y; +} + +} /* end of gf namespace */ + +#define MSG_CNT 3 // message-length polynomials count +#define POLY_CNT 14 // (ecc_length*2)-length polynomialc count + +class ReedSolomon { +public: + const uint8_t msg_length; + const uint8_t ecc_length; + + uint8_t * generator_cache = nullptr; + bool generator_cached = false; + + ReedSolomon(uint8_t msg_length_p, uint8_t ecc_length_p) : + msg_length(msg_length_p), ecc_length(ecc_length_p) { + generator_cache = new uint8_t[ecc_length + 1]; + + const uint8_t enc_len = msg_length + ecc_length; + const uint8_t poly_len = ecc_length * 2; + uint8_t** memptr = &memory; + uint16_t offset = 0; + + /* Initialize first six polys manually cause their amount depends on template parameters */ + + polynoms[0].Init(ID_MSG_IN, offset, enc_len, memptr); + offset += enc_len; + + polynoms[1].Init(ID_MSG_OUT, offset, enc_len, memptr); + offset += enc_len; + + for(uint8_t i = ID_GENERATOR; i < ID_MSG_E; i++) { + polynoms[i].Init(i, offset, poly_len, memptr); + offset += poly_len; + } + + polynoms[5].Init(ID_MSG_E, offset, enc_len, memptr); + offset += enc_len; + + for(uint8_t i = ID_TPOLY3; i < ID_ERR_EVAL+2; i++) { + polynoms[i].Init(i, offset, poly_len, memptr); + offset += poly_len; + } + } + + ~ReedSolomon() { + delete [] generator_cache; + // Dummy destructor, gcc-generated one crashes programm + memory = NULL; + } + + /* @brief Message block encoding + * @param *src - input message buffer (msg_lenth size) + * @param *dst - output buffer for ecc (ecc_length size at least) */ + void EncodeBlock(const void* src, void* dst) { + assert(msg_length + ecc_length < 256); + + ///* Allocating memory on stack for polynomials storage */ + uint8_t stack_memory[MSG_CNT * msg_length + POLY_CNT * ecc_length * 2]; + this->memory = stack_memory; + + // gg : allocation is now on the heap + //std::vector stack_memory(MSG_CNT * msg_length + POLY_CNT * ecc_length * 2); + //this->memory = stack_memory.data(); + + const uint8_t* src_ptr = (const uint8_t*) src; + uint8_t* dst_ptr = (uint8_t*) dst; + + Poly *msg_in = &polynoms[ID_MSG_IN]; + Poly *msg_out = &polynoms[ID_MSG_OUT]; + Poly *gen = &polynoms[ID_GENERATOR]; + + // Weird shit, but without reseting msg_in it simply doesn't work + msg_in->Reset(); + msg_out->Reset(); + + // Using cached generator or generating new one + if(generator_cached) { + gen->Set(generator_cache, ecc_length + 1); + } else { + GeneratorPoly(); + memcpy(generator_cache, gen->ptr(), gen->length); + generator_cached = true; + } + + // Copying input message to internal polynomial + msg_in->Set(src_ptr, msg_length); + msg_out->Set(src_ptr, msg_length); + msg_out->length = msg_in->length + ecc_length; + + // Here all the magic happens + uint8_t coef = 0; // cache + for(uint8_t i = 0; i < msg_length; i++){ + coef = msg_out->at(i); + if(coef != 0){ + for(uint32_t j = 1; j < gen->length; j++){ + msg_out->at(i+j) ^= gf::mul(gen->at(j), coef); + } + } + } + + // Copying ECC to the output buffer + memcpy(dst_ptr, msg_out->ptr()+msg_length, ecc_length * sizeof(uint8_t)); + } + + /* @brief Message encoding + * @param *src - input message buffer (msg_lenth size) + * @param *dst - output buffer (msg_length + ecc_length size at least) */ + void Encode(const void* src, void* dst) { + uint8_t* dst_ptr = (uint8_t*) dst; + + // Copying message to the output buffer + memcpy(dst_ptr, src, msg_length * sizeof(uint8_t)); + + // Calling EncodeBlock to write ecc to out[ut buffer + EncodeBlock(src, dst_ptr+msg_length); + } + + /* @brief Message block decoding + * @param *src - encoded message buffer (msg_length size) + * @param *ecc - ecc buffer (ecc_length size) + * @param *msg_out - output buffer (msg_length size at least) + * @param *erase_pos - known errors positions + * @param erase_count - count of known errors + * @return RESULT_SUCCESS if successfull, error code otherwise */ + int DecodeBlock(const void* src, const void* ecc, void* dst, uint8_t* erase_pos = NULL, size_t erase_count = 0) { + assert(msg_length + ecc_length < 256); + + const uint8_t *src_ptr = (const uint8_t*) src; + const uint8_t *ecc_ptr = (const uint8_t*) ecc; + uint8_t *dst_ptr = (uint8_t*) dst; + + const uint8_t src_len = msg_length + ecc_length; + const uint8_t dst_len = msg_length; + + bool ok; + + ///* Allocation memory on stack */ + uint8_t stack_memory[MSG_CNT * msg_length + POLY_CNT * ecc_length * 2]; + this->memory = stack_memory; + + // gg : allocation is now on the heap + //std::vector stack_memory(MSG_CNT * msg_length + POLY_CNT * ecc_length * 2); + //this->memory = stack_memory.data(); + + Poly *msg_in = &polynoms[ID_MSG_IN]; + Poly *msg_out = &polynoms[ID_MSG_OUT]; + Poly *epos = &polynoms[ID_ERASURES]; + + // Copying message to polynomials memory + msg_in->Set(src_ptr, msg_length); + msg_in->Set(ecc_ptr, ecc_length, msg_length); + msg_out->Copy(msg_in); + + // Copying known errors to polynomial + if(erase_pos == NULL) { + epos->length = 0; + } else { + epos->Set(erase_pos, erase_count); + for(uint8_t i = 0; i < epos->length; i++){ + msg_in->at(epos->at(i)) = 0; + } + } + + // Too many errors + if(epos->length > ecc_length) return 1; + + Poly *synd = &polynoms[ID_SYNDROMES]; + Poly *eloc = &polynoms[ID_ERRORS_LOC]; + Poly *reloc = &polynoms[ID_TPOLY1]; + Poly *err = &polynoms[ID_ERRORS]; + Poly *forney = &polynoms[ID_FORNEY]; + + // Calculating syndrome + CalcSyndromes(msg_in); + + // Checking for errors + bool has_errors = false; + for(uint8_t i = 0; i < synd->length; i++) { + if(synd->at(i) != 0) { + has_errors = true; + break; + } + } + + // Going to exit if no errors + if(!has_errors) goto return_corrected_msg; + + CalcForneySyndromes(synd, epos, src_len); + FindErrorLocator(forney, NULL, epos->length); + + // Reversing syndrome + // TODO optimize through special Poly flag + reloc->length = eloc->length; + for(int8_t i = eloc->length-1, j = 0; i >= 0; i--, j++){ + reloc->at(j) = eloc->at(i); + } + + // Fing errors + ok = FindErrors(reloc, src_len); + if(!ok) return 1; + + // Error happened while finding errors (so helpfull :D) + if(err->length == 0) return 1; + + /* Adding found errors with known */ + for(uint8_t i = 0; i < err->length; i++) { + epos->Append(err->at(i)); + } + + // Correcting errors + CorrectErrata(synd, epos, msg_in); + +return_corrected_msg: + // Wrighting corrected message to output buffer + msg_out->length = dst_len; + memcpy(dst_ptr, msg_out->ptr(), msg_out->length * sizeof(uint8_t)); + return 0; + } + + /* @brief Message block decoding + * @param *src - encoded message buffer (msg_length + ecc_length size) + * @param *msg_out - output buffer (msg_length size at least) + * @param *erase_pos - known errors positions + * @param erase_count - count of known errors + * @return RESULT_SUCCESS if successfull, error code otherwise */ + int Decode(const void* src, void* dst, uint8_t* erase_pos = NULL, size_t erase_count = 0) { + const uint8_t *src_ptr = (const uint8_t*) src; + const uint8_t *ecc_ptr = src_ptr + msg_length; + + return DecodeBlock(src, ecc_ptr, dst, erase_pos, erase_count); + } + +#ifndef DEBUG +private: +#endif + + enum POLY_ID { + ID_MSG_IN = 0, + ID_MSG_OUT, + ID_GENERATOR, // 3 + ID_TPOLY1, // T for Temporary + ID_TPOLY2, + + ID_MSG_E, // 5 + + ID_TPOLY3, // 6 + ID_TPOLY4, + + ID_SYNDROMES, + ID_FORNEY, + + ID_ERASURES_LOC, + ID_ERRORS_LOC, + + ID_ERASURES, + ID_ERRORS, + + ID_COEF_POS, + ID_ERR_EVAL + }; + + // Pointer for polynomials memory on stack + uint8_t* memory; + Poly polynoms[MSG_CNT + POLY_CNT]; + + void GeneratorPoly() { + Poly *gen = polynoms + ID_GENERATOR; + gen->at(0) = 1; + gen->length = 1; + + Poly *mulp = polynoms + ID_TPOLY1; + Poly *temp = polynoms + ID_TPOLY2; + mulp->length = 2; + + for(int8_t i = 0; i < ecc_length; i++){ + mulp->at(0) = 1; + mulp->at(1) = gf::pow(2, i); + + gf::poly_mul(gen, mulp, temp); + + gen->Copy(temp); + } + } + + void CalcSyndromes(const Poly *msg) { + Poly *synd = &polynoms[ID_SYNDROMES]; + synd->length = ecc_length+1; + synd->at(0) = 0; + for(uint8_t i = 1; i < ecc_length+1; i++){ + synd->at(i) = gf::poly_eval(msg, gf::pow(2, i-1)); + } + } + + void FindErrataLocator(const Poly *epos) { + Poly *errata_loc = &polynoms[ID_ERASURES_LOC]; + Poly *mulp = &polynoms[ID_TPOLY1]; + Poly *addp = &polynoms[ID_TPOLY2]; + Poly *apol = &polynoms[ID_TPOLY3]; + Poly *temp = &polynoms[ID_TPOLY4]; + + errata_loc->length = 1; + errata_loc->at(0) = 1; + + mulp->length = 1; + addp->length = 2; + + for(uint8_t i = 0; i < epos->length; i++){ + mulp->at(0) = 1; + addp->at(0) = gf::pow(2, epos->at(i)); + addp->at(1) = 0; + + gf::poly_add(mulp, addp, apol); + gf::poly_mul(errata_loc, apol, temp); + + errata_loc->Copy(temp); + } + } + + void FindErrorEvaluator(const Poly *synd, const Poly *errata_loc, Poly *dst, uint8_t ecclen) { + Poly *mulp = &polynoms[ID_TPOLY1]; + gf::poly_mul(synd, errata_loc, mulp); + + Poly *divisor = &polynoms[ID_TPOLY2]; + divisor->length = ecclen+2; + + divisor->Reset(); + divisor->at(0) = 1; + + gf::poly_div(mulp, divisor, dst); + } + + void CorrectErrata(const Poly *synd, const Poly *err_pos, const Poly *msg_in) { + Poly *c_pos = &polynoms[ID_COEF_POS]; + Poly *corrected = &polynoms[ID_MSG_OUT]; + c_pos->length = err_pos->length; + + for(uint8_t i = 0; i < err_pos->length; i++) + c_pos->at(i) = msg_in->length - 1 - err_pos->at(i); + + /* uses t_poly 1, 2, 3, 4 */ + FindErrataLocator(c_pos); + Poly *errata_loc = &polynoms[ID_ERASURES_LOC]; + + /* reversing syndromes */ + Poly *rsynd = &polynoms[ID_TPOLY3]; + rsynd->length = synd->length; + + for(int8_t i = synd->length-1, j = 0; i >= 0; i--, j++) { + rsynd->at(j) = synd->at(i); + } + + /* getting reversed error evaluator polynomial */ + Poly *re_eval = &polynoms[ID_TPOLY4]; + + /* uses T_POLY 1, 2 */ + FindErrorEvaluator(rsynd, errata_loc, re_eval, errata_loc->length-1); + + /* reversing it back */ + Poly *e_eval = &polynoms[ID_ERR_EVAL]; + e_eval->length = re_eval->length; + for(int8_t i = re_eval->length-1, j = 0; i >= 0; i--, j++) { + e_eval->at(j) = re_eval->at(i); + } + + Poly *X = &polynoms[ID_TPOLY1]; /* this will store errors positions */ + X->length = 0; + + int16_t l; + for(uint8_t i = 0; i < c_pos->length; i++){ + l = 255 - c_pos->at(i); + X->Append(gf::pow(2, -l)); + } + + /* Magnitude polynomial + Shit just got real */ + Poly *E = &polynoms[ID_MSG_E]; + E->Reset(); + E->length = msg_in->length; + + uint8_t Xi_inv; + + Poly *err_loc_prime_temp = &polynoms[ID_TPOLY2]; + + uint8_t err_loc_prime; + uint8_t y; + + for(uint8_t i = 0; i < X->length; i++){ + Xi_inv = gf::inverse(X->at(i)); + + err_loc_prime_temp->length = 0; + for(uint8_t j = 0; j < X->length; j++){ + if(j != i){ + err_loc_prime_temp->Append(gf::sub(1, gf::mul(Xi_inv, X->at(j)))); + } + } + + err_loc_prime = 1; + for(uint8_t j = 0; j < err_loc_prime_temp->length; j++){ + err_loc_prime = gf::mul(err_loc_prime, err_loc_prime_temp->at(j)); + } + + y = gf::poly_eval(re_eval, Xi_inv); + y = gf::mul(gf::pow(X->at(i), 1), y); + + E->at(err_pos->at(i)) = gf::div(y, err_loc_prime); + } + + gf::poly_add(msg_in, E, corrected); + } + + bool FindErrorLocator(const Poly *synd, Poly *erase_loc = NULL, size_t erase_count = 0) { + Poly *error_loc = &polynoms[ID_ERRORS_LOC]; + Poly *err_loc = &polynoms[ID_TPOLY1]; + Poly *old_loc = &polynoms[ID_TPOLY2]; + Poly *temp = &polynoms[ID_TPOLY3]; + Poly *temp2 = &polynoms[ID_TPOLY4]; + + if(erase_loc != NULL) { + err_loc->Copy(erase_loc); + old_loc->Copy(erase_loc); + } else { + err_loc->length = 1; + old_loc->length = 1; + err_loc->at(0) = 1; + old_loc->at(0) = 1; + } + + uint8_t synd_shift = 0; + if(synd->length > ecc_length) { + synd_shift = synd->length - ecc_length; + } + + uint8_t K = 0; + uint8_t delta = 0; + uint8_t index; + + for(uint8_t i = 0; i < ecc_length - erase_count; i++){ + if(erase_loc != NULL) + K = erase_count + i + synd_shift; + else + K = i + synd_shift; + + delta = synd->at(K); + for(uint8_t j = 1; j < err_loc->length; j++) { + index = err_loc->length - j - 1; + delta ^= gf::mul(err_loc->at(index), synd->at(K-j)); + } + + old_loc->Append(0); + + if(delta != 0) { + if(old_loc->length > err_loc->length) { + gf::poly_scale(old_loc, temp, delta); + gf::poly_scale(err_loc, old_loc, gf::inverse(delta)); + err_loc->Copy(temp); + } + gf::poly_scale(old_loc, temp, delta); + gf::poly_add(err_loc, temp, temp2); + err_loc->Copy(temp2); + } + } + + uint32_t shift = 0; + while(err_loc->length && err_loc->at(shift) == 0) shift++; + + uint32_t errs = err_loc->length - shift - 1; + if(((errs - erase_count) * 2 + erase_count) > ecc_length){ + return false; /* Error count is greater then we can fix! */ + } + + memcpy(error_loc->ptr(), err_loc->ptr() + shift, (err_loc->length - shift) * sizeof(uint8_t)); + error_loc->length = (err_loc->length - shift); + return true; + } + + bool FindErrors(const Poly *error_loc, size_t msg_in_size) { + Poly *err = &polynoms[ID_ERRORS]; + + uint8_t errs = error_loc->length - 1; + err->length = 0; + + for(uint8_t i = 0; i < msg_in_size; i++) { + if(gf::poly_eval(error_loc, gf::pow(2, i)) == 0) { + err->Append(msg_in_size - 1 - i); + } + } + + /* Sanity check: + * the number of err/errata positions found + * should be exactly the same as the length of the errata locator polynomial */ + if(err->length != errs) + /* couldn't find error locations */ + return false; + return true; + } + + void CalcForneySyndromes(const Poly *synd, const Poly *erasures_pos, size_t msg_in_size) { + Poly *erase_pos_reversed = &polynoms[ID_TPOLY1]; + Poly *forney_synd = &polynoms[ID_FORNEY]; + erase_pos_reversed->length = 0; + + for(uint8_t i = 0; i < erasures_pos->length; i++){ + erase_pos_reversed->Append(msg_in_size - 1 - erasures_pos->at(i)); + } + + forney_synd->Reset(); + forney_synd->Set(synd->ptr()+1, synd->length-1); + + uint8_t x; + for(uint8_t i = 0; i < erasures_pos->length; i++) { + x = gf::pow(2, erase_pos_reversed->at(i)); + for(int8_t j = 0; j < forney_synd->length - 1; j++){ + forney_synd->at(j) = gf::mul(forney_synd->at(j), x) ^ forney_synd->at(j+1); + } + } + } +}; + +} + +namespace GGWave { + +// Direct-sequence spread magic numbers +// Used to xor the actual payload +const uint8_t kDSSMagic[] = { + 0x96, 0x9f, 0xb4, 0xaf, 0x1b, 0x91, 0xde, 0xc5, 0x45, 0x75, 0xe8, 0x2e, 0x0f, 0x32, 0x4a, 0x5f, + 0xb4, 0x56, 0x95, 0xcb, 0x7f, 0x6a, 0x54, 0x6a, 0x48, 0xf2, 0x0b, 0x7b, 0xcd, 0xfb, 0x93, 0x6d, + 0x3c, 0x77, 0x5e, 0xc3, 0x33, 0x47, 0xc0, 0xf1, 0x71, 0x32, 0x33, 0x27, 0x35, 0x68, 0x47, 0x1f, + 0x4e, 0xac, 0x23, 0x42, 0x5f, 0x00, 0x37, 0xa4, 0x50, 0x6d, 0x48, 0x24, 0x91, 0x7c, 0xa1, 0x4e, +}; + +uint8_t mymax(uint8_t a, uint8_t b) { + return (a > b) ? a : b; +} + +uint8_t getECCBytesForLength(uint8_t len) { + return len < 4 ? 2 : mymax(4, 2*(len/5)); +} + +const uint8_t kDataLength_bytes = 16; +const uint8_t kECCLength_bytes = getECCBytesForLength(kDataLength_bytes); + +typedef enum { + TX_ARDUINO_512_NORMAL, + TX_ARDUINO_512_FAST, + TX_ARDUINO_512_FASTEST, + TX_ARDUINO_1024_NORMAL, + TX_ARDUINO_1024_FAST, + TX_ARDUINO_1024_FASTEST, +} TxProtocolId; + +struct Parameters { + int sampleRate; + uint8_t freqStart; + uint8_t timePerFrame_ms; +}; + +void send(uint8_t pin, const uint8_t * data, const Parameters & parameters) { + const float dF = 48000.0/float(parameters.sampleRate); + + char buf[kDataLength_bytes]; + char enc[kDataLength_bytes + kECCLength_bytes]; + + for (uint8_t i = 0; i < kDataLength_bytes; i++) { + buf[i] = data[i] ^ kDSSMagic[i%sizeof(kDSSMagic)]; + } + + RS::ReedSolomon rsLength(kDataLength_bytes, kECCLength_bytes); + rsLength.Encode(buf, enc); + + float fcur = 0.0f; + for (int i = 0; i < 2*(kDataLength_bytes + kECCLength_bytes); i++) { + uint8_t cur = enc[i/2]; + if (i%2 == 0) { + cur = cur & 0x0F; + } else { + cur = cur >> 4; + } + + fcur = float(parameters.freqStart)*dF + float(cur)*dF; + + tone(pin, fcur); + delay(parameters.timePerFrame_ms); + } + + noTone(pin); +} + +void send(uint8_t pin, const uint8_t * data, TxProtocolId protocolId = TX_ARDUINO_512_FASTEST) { + Parameters parameters = { 512, 16, 32 }; + + switch (protocolId) { + case TX_ARDUINO_512_NORMAL: parameters = { 512, 16, 96 }; break; + case TX_ARDUINO_512_FAST: parameters = { 512, 16, 64 }; break; + case TX_ARDUINO_512_FASTEST: parameters = { 512, 16, 32 }; break; + case TX_ARDUINO_1024_NORMAL: parameters = { 1024, 16, 192 }; break; + case TX_ARDUINO_1024_FAST: parameters = { 1024, 16, 128 }; break; + case TX_ARDUINO_1024_FASTEST: parameters = { 1024, 16, 64 }; break; + }; + + send(pin, data, parameters); +} + +void send_text(uint8_t pin, const char * text, TxProtocolId protocolId = TX_ARDUINO_512_FASTEST) { + char tx[kDataLength_bytes]; + memset(tx, 0, sizeof(tx)); + strncpy(tx, text, sizeof(tx)); + send(pin, tx, protocolId); +} + +}