tnc3-firmware/TNC/AFSKModulator.hpp

193 wiersze
5.4 KiB
C++

// Copyright 2015 Robert C. Riggs <rob@pangalactic.org>
// All rights reserved.
#ifndef MOBILINKD__TNC__AFSK_MODULATOR_HPP_
#define MOBILINKD__TNC__AFSK_MODULATOR_HPP_
#include <stddef.h>
#include "PTT.hpp"
#include "Log.h"
#include "stm32l4xx_hal.h"
#include "cmsis_os.h"
#include "main.h"
#include <algorithm>
extern osMessageQId hdlcOutputQueueHandle;
extern osMessageQId dacOutputQueueHandle;
extern TIM_HandleTypeDef htim7;
extern DAC_HandleTypeDef hdac1;
namespace mobilinkd { namespace tnc {
const size_t SIN_TABLE_LEN = 264;
const int16_t sin_table[SIN_TABLE_LEN] = {
2048, 2096, 2145, 2194, 2242, 2291, 2339, 2387,
2435, 2483, 2530, 2577, 2624, 2671, 2717, 2763,
2808, 2853, 2898, 2942, 2985, 3029, 3071, 3113,
3154, 3195, 3235, 3274, 3313, 3351, 3388, 3424,
3460, 3495, 3529, 3562, 3595, 3626, 3657, 3686,
3715, 3743, 3770, 3795, 3820, 3844, 3867, 3889,
3910, 3929, 3948, 3965, 3982, 3997, 4012, 4025,
4037, 4048, 4058, 4066, 4074, 4080, 4085, 4089,
4092, 4094, 4095, 4094, 4092, 4089, 4085, 4080,
4074, 4066, 4058, 4048, 4037, 4025, 4012, 3997,
3982, 3965, 3948, 3929, 3910, 3889, 3867, 3844,
3820, 3795, 3770, 3743, 3715, 3686, 3657, 3626,
3595, 3562, 3529, 3495, 3460, 3424, 3388, 3351,
3313, 3274, 3235, 3195, 3154, 3113, 3071, 3029,
2985, 2942, 2898, 2853, 2808, 2763, 2717, 2671,
2624, 2577, 2530, 2483, 2435, 2387, 2339, 2291,
2242, 2194, 2145, 2096, 2048, 1999, 1950, 1901,
1853, 1804, 1756, 1708, 1660, 1612, 1565, 1518,
1471, 1424, 1378, 1332, 1287, 1242, 1197, 1153,
1110, 1066, 1024, 982, 941, 900, 860, 821,
782, 744, 707, 671, 635, 600, 566, 533,
500, 469, 438, 409, 380, 352, 325, 300,
275, 251, 228, 206, 185, 166, 147, 130,
113, 98, 83, 70, 58, 47, 37, 29,
21, 15, 10, 6, 3, 1, 1, 1,
3, 6, 10, 15, 21, 29, 37, 47,
58, 70, 83, 98, 113, 130, 147, 166,
185, 206, 228, 251, 275, 300, 325, 352,
380, 409, 438, 469, 500, 533, 566, 600,
635, 671, 707, 744, 782, 821, 860, 900,
941, 982, 1024, 1066, 1110, 1153, 1197, 1242,
1287, 1332, 1378, 1424, 1471, 1518, 1565, 1612,
1660, 1708, 1756, 1804, 1853, 1901, 1950, 1999,
};
struct AFSKModulator {
static const size_t DAC_BUFFER_LEN = 44;
static const size_t BIT_LEN = DAC_BUFFER_LEN / 2;
static const size_t MARK_SKIP = 12;
static const size_t SPACE_SKIP = 22;
size_t pos_{0};
int running_{-1};
osMessageQId dacOutputQueueHandle_;
PTT* ptt_;
uint8_t twist_{50};
uint16_t volume_{4096};
uint16_t buffer_[DAC_BUFFER_LEN];
AFSKModulator(osMessageQId queue, PTT* ptt)
: dacOutputQueueHandle_(queue), ptt_(ptt)
{
for (size_t i = 0; i != DAC_BUFFER_LEN; i++)
buffer_[i] = 2048;
}
void set_volume(uint16_t v)
{
v = std::max<uint16_t>(256, v);
v = std::min<uint16_t>(4096, v);
volume_ = v;
}
void set_ptt(PTT* ptt) {
if (ptt == ptt_) return; // No change.
auto old = ptt_;
ptt_ = ptt;
old->off();
if (running_ == 1) {
ptt_->on();
}
}
void set_twist(uint8_t twist) {twist_ = twist;}
void send(bool bit) {
switch (running_) {
case -1:
fill_first(bit);
running_ = 0;
break;
case 0:
fill_last(bit);
running_ = 1;
ptt_->on();
HAL_TIM_Base_Start(&htim7);
HAL_DAC_Start_DMA(&hdac1, DAC_CHANNEL_1, (uint32_t*) buffer_, DAC_BUFFER_LEN, DAC_ALIGN_12B_R);
break;
case 1:
osMessagePut(dacOutputQueueHandle_, bit, osWaitForever);
break;
}
}
void fill(uint16_t* buffer, bool bit) {
for (size_t i = 0; i != BIT_LEN; i++) {
int s = sin_table[pos_];
s -= 2048;
s *= volume_;
s >>= 12;
s += 2048;
if (bit) {
if (twist_ > 50) {
s = (((s - 2048) * (100 - twist_)) / 50) + 2048;
}
} else {
if (twist_ < 50) {
s = (((s - 2048) * twist_) / 50) + 2048;
}
}
if (s < 0 or s > 4095) {
DEBUG("DAC inversion (%d)", s);
}
*buffer = uint16_t(s);
++buffer;
pos_ += (bit ? MARK_SKIP : SPACE_SKIP);
if (pos_ >= SIN_TABLE_LEN) pos_ -= SIN_TABLE_LEN;
}
}
void fill_first(bool bit) {
fill(buffer_, bit);
}
void fill_last(bool bit) {
fill(buffer_ + BIT_LEN, bit);
}
void empty() {
switch (running_) {
case 1:
running_ = 0;
break;
case 0:
running_ = -1;
HAL_DAC_Stop_DMA(&hdac1, DAC_CHANNEL_1);
HAL_TIM_Base_Stop(&htim7);
ptt_->off();
pos_ = 0;
break;
case -1:
break;
}
}
void abort() {
running_ = -1;
HAL_DAC_Stop_DMA(&hdac1, DAC_CHANNEL_1);
HAL_TIM_Base_Stop(&htim7);
ptt_->off();
pos_ = 0;
// Drain the queue.
while (osMessageGet(dacOutputQueueHandle_, 0).status == osEventMessage);
}
};
}} // mobilinkd::tnc
#endif // MOBILINKD__TNC__AFSK_MODULATOR_HPP_