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Refactoring of MDx tone generator, adding support for AFSK encoding (not yet implemented) and reproduction of arbitrary audio streams.

replace/7114298ab9fc89922f8777525d4c5a7e93980b7f
Silvano Seva 2021-04-09 11:30:58 +02:00
rodzic 8045a9bcea
commit 311a89ac0f
4 zmienionych plików z 408 dodań i 203 usunięć
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6
meson.build
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@ -163,7 +163,7 @@ md3x0_src = src + stm32f405_src + ['platform/drivers/display/HX8353_MDx.cpp',
'platform/drivers/NVM/spiFlash_MDx.c',
'platform/drivers/NVM/nvmem_MD3x0.c',
'platform/drivers/ADC/ADC1_MDx.c',
'platform/drivers/tones/toneGenerator_MDx.c',
'platform/drivers/tones/toneGenerator_MDx.cpp',
'platform/drivers/baseband/SKY72310.c',
'platform/drivers/baseband/radio_MD3x0.c',
'platform/drivers/baseband/HR_C5000.c',
@ -181,7 +181,7 @@ mduv3x0_src = src + stm32f405_src + ['platform/drivers/display/HX8353_MDx.cpp',
'platform/drivers/NVM/spiFlash_MDx.c',
'platform/drivers/NVM/nvmem_MDUV3x0.c',
'platform/drivers/ADC/ADC1_MDx.c',
'platform/drivers/tones/toneGenerator_MDx.c',
'platform/drivers/tones/toneGenerator_MDx.cpp',
'platform/drivers/baseband/radio_UV3x0.c',
'platform/drivers/GPS/GPS_MDx.cpp',
'platform/targets/MD-UV3x0/platform.c',
@ -195,7 +195,7 @@ mduv3x0_def = def + stm32f405_def + {'PLATFORM_MDUV3x0': ''}
## TYT MD-9600
md9600_src = src + stm32f405_src + ['platform/targets/MD-9600/platform.c',
'platform/drivers/tones/toneGenerator_MDx.c']
'platform/drivers/tones/toneGenerator_MDx.cpp']
md9600_inc = inc + stm32f405_inc + ['platform/targets/MD-9600']
md9600_def = def + stm32f405_def + {'PLATFORM_MD9600': ''}

182
platform/drivers/tones/toneGenerator_MDx.c
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@ -1,182 +0,0 @@
/***************************************************************************
* Copyright (C) 2020 by Federico Amedeo Izzo IU2NUO, *
* Niccolò Izzo IU2KIN *
* Frederik Saraci IU2NRO *
* Silvano Seva IU2KWO *
* *
* 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 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 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 "toneGenerator_MDx.h"
#include <hwconfig.h>
#include <interfaces/gpio.h>
/*
* Sine table for PWM-based sinewave generation, containing 256 samples over one
* period of a 64Hz sinewave. This gives a PWM base frequency of 16.384kHz.
*/
static const uint8_t sineTable[] =
{
128,131,134,137,140,143,146,149,152,155,158,162,165,167,170,173,176,179,182,
185,188,190,193,196,198,201,203,206,208,211,213,215,218,220,222,224,226,228,
230,232,234,235,237,238,240,241,243,244,245,246,248,249,250,250,251,252,253,
253,254,254,254,255,255,255,255,255,255,255,254,254,254,253,253,252,251,250,
250,249,248,246,245,244,243,241,240,238,237,235,234,232,230,228,226,224,222,
220,218,215,213,211,208,206,203,201,198,196,193,190,188,185,182,179,176,173,
170,167,165,162,158,155,152,149,146,143,140,137,134,131,128,124,121,118,115,
112,109,106,103,100,97,93,90,88,85,82,79,76,73,70,67,65,62,59,57,54,52,49,47,
44,42,40,37,35,33,31,29,27,25,23,21,20,18,17,15,14,12,11,10,9,7,6,5,5,4,3,2,
2,1,1,1,0,0,0,0,0,0,0,1,1,1,2,2,3,4,5,5,6,7,9,10,11,12,14,15,17,18,20,21,23,
25,27,29,31,33,35,37,40,42,44,47,49,52,54,57,59,62,65,67,70,73,76,79,82,85,88,
90,93,97,100,103,106,109,112,115,118,121,124
};
/*
* Correction factor to compensate for the (slight) difference between the exact
* sampling frequency of the sine table and the PWM frequency generated by the
* timer. This difference causes a frequency error in the resulting output of
* both CTCSS and "beep" signals.
* To compensate for this, simply multiply the target frequency by this
* correction factor.
*/
const float freqCorrFactor = 16384.0f/16406.25;
const uint32_t baseSineFreq = 64;
uint32_t toneTableIndex = 0; /* Current sine table index for CTCSS generator */
uint32_t toneTableIncr = 0; /* CTCSS sine table index increment per tick */
uint32_t beepTableIndex = 0; /* Current sine table index for "beep" generator */
uint32_t beepTableIncr = 0; /* "beep" sine table index increment per tick */
uint32_t beepTimerCount = 0; /* Downcounter for timed "beep" */
/* Name-mangled function name, for C++ compatibility */
void __attribute__((used)) _Z15TIM3_IRQHandlerv()
{
toneTableIndex += toneTableIncr;
beepTableIndex += beepTableIncr;
TIM3->CCR2 = sineTable[(toneTableIndex >> 16) & 0xFF];
TIM3->CCR3 = sineTable[(beepTableIndex >> 16) & 0xFF];
TIM3->SR = 0;
if(beepTimerCount > 0)
{
beepTimerCount--;
if(beepTimerCount == 0)
{
TIM3->CCER &= ~TIM_CCER_CC3E;
}
}
/* Shutdown timer if both compare channels are inactive */
if((TIM3->CCER & (TIM_CCER_CC2E | TIM_CCER_CC3E)) == 0)
{
TIM3->CR1 &= ~TIM_CR1_CEN;
}
}
void toneGen_init()
{
/*
* Configure GPIOs:
* - CTCSS output is on PC7 (on MD380), that is TIM3-CH2, AF2
* - "beep" output is on PC8 (on MD380), that is TIM3-CH3, AF2
*/
gpio_setMode(CTCSS_OUT, ALTERNATE);
gpio_setMode(BEEP_OUT, ALTERNATE);
gpio_setAlternateFunction(CTCSS_OUT, 2);
gpio_setAlternateFunction(BEEP_OUT, 2);
/*
* Timer configuration:
* - APB1 frequency = 42MHz but timer run at twice of this frequency: with
* 1:20 prescaler we have Ftick = 4.2MHz
* - ARR = 255 (8-bit PWM), gives an update rate of 16.406kHz
* - Nominal update rate is 16.384kHz -> error = +22.25Hz
*/
RCC->APB1ENR |= RCC_APB1ENR_TIM3EN;
__DSB();
TIM3->ARR = 0xFF;
TIM3->PSC = 19;
TIM3->CCMR1 = TIM_CCMR1_OC2M_2 /* CH2 in PWM mode 1, preload enabled */
| TIM_CCMR1_OC2M_1
| TIM_CCMR1_OC2PE;
TIM3->CCMR2 = TIM_CCMR2_OC3M_2 /* The same for CH3 */
| TIM_CCMR2_OC3M_1
| TIM_CCMR2_OC3PE;
TIM3->DIER |= TIM_DIER_UIE; /* Interrupt on counter update */
TIM3->CR1 |= TIM_CR1_ARPE; /* Enable auto preload on reload */
NVIC_SetPriority(TIM3_IRQn, 10);
NVIC_EnableIRQ(TIM3_IRQn);
}
void toneGen_terminate()
{
RCC->APB1ENR &= ~RCC_APB1ENR_TIM3EN;
__DSB();
gpio_setMode(CTCSS_OUT, INPUT);
gpio_setMode(BEEP_OUT, INPUT);
}
void toneGen_setToneFreq(float toneFreq)
{
/*
* Convert to 16.16 fixed point number, then divide by the frequency of
* sinewave stored in the PWM table
*/
float dividend = toneFreq * freqCorrFactor * 65536.0f;
toneTableIncr = ((uint32_t) dividend)/baseSineFreq;
}
void toneGen_toneOn()
{
TIM3->CCER |= TIM_CCER_CC2E;
TIM3->CR1 |= TIM_CR1_CEN;
}
void toneGen_toneOff()
{
TIM3->CCER &= ~TIM_CCER_CC2E;
}
void toneGen_setBeepFreq(float beepFreq)
{
float dividend = beepFreq * freqCorrFactor * 65536.0f;
beepTableIncr = ((uint32_t) dividend)/baseSineFreq;
}
void toneGen_beepOn()
{
TIM3->CCER |= TIM_CCER_CC3E;
TIM3->CR1 |= TIM_CR1_CEN;
}
void toneGen_beepOff()
{
TIM3->CCER &= ~TIM_CCER_CC3E;
}
void toneGen_timedBeep(uint16_t duration)
{
/*
* Duration is in milliseconds, while counter update rate is 16.406kHz.
* Thus, the value for downcounter is (duration * 16.406)/1000.
*/
beepTimerCount = (duration * 16406)/1000;
TIM3->CCER |= TIM_CCER_CC3E;
TIM3->CR1 |= TIM_CR1_CEN;
}

339
platform/drivers/tones/toneGenerator_MDx.cpp 100644
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@ -0,0 +1,339 @@
/***************************************************************************
* Copyright (C) 2020 by Federico Amedeo Izzo IU2NUO, *
* Niccolò Izzo IU2KIN *
* Frederik Saraci IU2NRO *
* Silvano Seva IU2KWO *
* *
* 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 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 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 "toneGenerator_MDx.h"
#include <miosix.h>
#include <hwconfig.h>
#include <interfaces/gpio.h>
#include <kernel/scheduler/scheduler.h>
#include <interfaces/delays.h>
#include <stdio.h>
/*
* Sine table for PWM-based sinewave generation, containing 256 samples over one
* period of a 35Hz sinewave. This gives a PWM base frequency of 8.96kHz.
*/
static const uint8_t sineTable[] =
{
128,131,134,137,140,143,146,149,152,155,158,162,165,167,170,173,176,179,182,
185,188,190,193,196,198,201,203,206,208,211,213,215,218,220,222,224,226,228,
230,232,234,235,237,238,240,241,243,244,245,246,248,249,250,250,251,252,253,
253,254,254,254,255,255,255,255,255,255,255,254,254,254,253,253,252,251,250,
250,249,248,246,245,244,243,241,240,238,237,235,234,232,230,228,226,224,222,
220,218,215,213,211,208,206,203,201,198,196,193,190,188,185,182,179,176,173,
170,167,165,162,158,155,152,149,146,143,140,137,134,131,128,124,121,118,115,
112,109,106,103,100,97,93,90,88,85,82,79,76,73,70,67,65,62,59,57,54,52,49,47,
44,42,40,37,35,33,31,29,27,25,23,21,20,18,17,15,14,12,11,10,9,7,6,5,5,4,3,2,
2,1,1,1,0,0,0,0,0,0,0,1,1,1,2,2,3,4,5,5,6,7,9,10,11,12,14,15,17,18,20,21,23,
25,27,29,31,33,35,37,40,42,44,47,49,52,54,57,59,62,65,67,70,73,76,79,82,85,
88,90,93,97,100,103,106,109,112,115,118,121,124
};
static const uint32_t baseSineFreq = 35;
uint32_t toneTableIndex = 0; /* Current sine table index for CTCSS generator */
uint32_t toneTableIncr = 0; /* CTCSS sine table index increment per tick */
uint32_t beepTableIndex = 0; /* Current sine table index for "beep" generator */
uint32_t beepTableIncr = 0; /* "beep" sine table index increment per tick */
uint32_t beepTimerCount = 0; /* Downcounter for timed "beep" */
uint8_t beepVolume = 0; /* "beep" volume level */
bool tonesLocked = false; /* If true tone channel is in use by FSK/playback */
using namespace miosix;
Thread *dmaWaiting = 0;
/*
* TIM14 interrupt handler, used to manage generation of CTCSS and "beep" tones.
*/
void __attribute__((used)) TIM8_TRG_COM_TIM14_IRQHandler()
{
TIM14->SR = 0;
toneTableIndex += toneTableIncr;
beepTableIndex += beepTableIncr;
TIM3->CCR2 = sineTable[(toneTableIndex >> 16) & 0xFF];
if(!tonesLocked)
{
TIM3->CCR3 = (sineTable[(beepTableIndex >> 16) & 0xFF] * beepVolume) >> 8;
}
if(beepTimerCount > 0)
{
beepTimerCount--;
if(beepTimerCount == 0)
{
TIM3->CCER &= ~TIM_CCER_CC3E;
}
}
/* Shutdown timers if both compare channels are inactive */
if((TIM3->CCER & (TIM_CCER_CC2E | TIM_CCER_CC3E)) == 0)
{
TIM3->CR1 &= ~TIM_CR1_CEN;
TIM14->CR1 &= ~TIM_CR1_CEN;
}
}
/*
* DMA1 Stream2 interrupt handler, for audio playback and FSK modulation.
*/
void __attribute__((used)) DMA_Handler()
{
DMA1->LIFCR |= DMA_LIFCR_CTCIF2 | DMA_LIFCR_CTEIF2;
if(dmaWaiting == 0) return;
dmaWaiting->IRQwakeup();
if(dmaWaiting->IRQgetPriority()>Thread::IRQgetCurrentThread()->IRQgetPriority())
Scheduler::IRQfindNextThread();
dmaWaiting = 0;
}
void __attribute__((naked)) DMA1_Stream2_IRQHandler()
{
saveContext();
asm volatile("bl _Z11DMA_Handlerv");
restoreContext();
}
void toneGen_init()
{
/*
* Configure GPIOs:
* - CTCSS output is on PC7 (on MD380), that is TIM3-CH2, AF2
* - "beep" output is on PC8 (on MD380), that is TIM3-CH3, AF2
*/
gpio_setMode(CTCSS_OUT, ALTERNATE);
gpio_setMode(BEEP_OUT, ALTERNATE);
gpio_setAlternateFunction(CTCSS_OUT, 2);
gpio_setAlternateFunction(BEEP_OUT, 2);
/*
* TIM3 configuration:
* - APB1 frequency = 42MHz but timer run at twice of this frequency: with
* 1:3 prescaler we have Ftick = 28MHz
* - ARR = 255 (8-bit PWM), gives a PWM frequency of 109.375kHz
*/
RCC->APB1ENR |= RCC_APB1ENR_TIM3EN;
__DSB();
TIM3->ARR = 0xFF;
TIM3->PSC = 2;
TIM3->CCMR1 = TIM_CCMR1_OC2M_2 /* CH2 in PWM mode 1, preload enabled */
| TIM_CCMR1_OC2M_1
| TIM_CCMR1_OC2PE;
TIM3->CCMR2 = TIM_CCMR2_OC3M_2 /* The same for CH3 */
| TIM_CCMR2_OC3M_1
| TIM_CCMR2_OC3PE;
TIM3->CR1 |= TIM_CR1_ARPE; /* Enable auto preload on reload */
/*
* TIM14 configuration:
* - APB1 frequency = 42MHz but timer run at twice of this frequency.
* - ARR = 9375 gives an update rate of 8.96kHz
*/
RCC->APB1ENR |= RCC_APB1ENR_TIM14EN;
__DSB();
TIM14->PSC = 0; /* 1:1 prescaler */
TIM14->ARR = 9375;
TIM14->CNT = 0;
TIM14->EGR = TIM_EGR_UG; /* Update registers */
TIM14->DIER = TIM_DIER_UIE; /* Interrupt on counter update */
NVIC_SetPriority(TIM8_TRG_COM_TIM14_IRQn, 10);
NVIC_EnableIRQ(TIM8_TRG_COM_TIM14_IRQn);
}
void toneGen_terminate()
{
RCC->APB1ENR &= ~(RCC_APB1ENR_TIM3EN |
RCC_APB1ENR_TIM14EN |
RCC_APB1ENR_TIM7EN);
RCC->AHB1ENR &= ~RCC_AHB1ENR_DMA1EN;
__DSB();
dmaWaiting->wakeup();
gpio_setMode(CTCSS_OUT, INPUT);
gpio_setMode(BEEP_OUT, INPUT);
}
void toneGen_setToneFreq(float toneFreq)
{
/*
* Convert to 16.16 fixed point number, then divide by the frequency of
* sinewave stored in the PWM table
*/
float dividend = toneFreq * 65536.0f;
toneTableIncr = ((uint32_t) dividend)/baseSineFreq;
}
void toneGen_toneOn()
{
TIM3->CCER |= TIM_CCER_CC2E;
TIM3->CR1 |= TIM_CR1_CEN;
TIM14->CR1 |= TIM_CR1_CEN;
}
void toneGen_toneOff()
{
TIM3->CCER &= ~TIM_CCER_CC2E;
}
void toneGen_beepOn(const float beepFreq, const uint8_t volume,
const uint32_t duration)
{
{
/* Do not generate "beep" if the PWM channel is busy, critical section */
FastInterruptDisableLock dLock;
if(tonesLocked) return;
}
float dividend = beepFreq * 65536.0f;
beepTableIncr = ((uint32_t) dividend)/baseSineFreq;
beepVolume = volume;
/*
* Duration is in milliseconds, while counter update rate is 8.96kHz.
* Thus, the value for downcounter is (duration * 8960)/1000.
*/
beepTimerCount = (duration * 8960)/1000;
TIM3->CCER |= TIM_CCER_CC3E;
TIM3->CR1 |= TIM_CR1_CEN;
TIM14->CR1 |= TIM_CR1_CEN;
}
void toneGen_beepOff()
{
/*
* Prevent disabling of tones if PWM channel is occupied by FSK/playback.
* Locking interrupts to avoid race conditions.
*/
FastInterruptDisableLock dLock;
if(tonesLocked) return;
TIM3->CCER &= ~TIM_CCER_CC3E;
}
void toneGen_encodeAFSK1200(const uint8_t* buf, const size_t len)
{
(void) buf;
(void) len;
}
void toneGen_playAudioStream(const uint16_t* buf, const size_t len,
const uint32_t sampleRate)
{
if((buf == NULL) || (len == 0) || (sampleRate == 0)) return;
{
/* Critical section to avoid race conditions on "tonesLocked" */
FastInterruptDisableLock dLock;
tonesLocked = true;
beepTimerCount = 0;
}
RCC->AHB1ENR |= RCC_AHB1ENR_DMA1EN;
RCC->APB1ENR |= RCC_APB1ENR_TIM7EN;
__DSB();
/*
* Timebase for triggering of DMA transfers.
* Bus frequency is 84MHz.
*/
uint32_t ratio = (84000000/sampleRate) - 1;
TIM7->CNT = 0;
TIM7->PSC = 0;
TIM7->ARR = ratio;
TIM7->EGR = TIM_EGR_UG;
TIM7->DIER = TIM_DIER_UDE;
/*
* DMA stream for sample transfer
*/
DMA1_Stream2->NDTR = len;
DMA1_Stream2->PAR = ((uint32_t) &(TIM3->CCR3));
DMA1_Stream2->M0AR = ((uint32_t) buf);
DMA1_Stream2->CR = DMA_SxCR_CHSEL_0 /* Channel 1 */
| DMA_SxCR_PL /* Very high priority */
| DMA_SxCR_MSIZE_0 /* 16 bit source size */
| DMA_SxCR_PSIZE_0 /* 16 bit destination size */
| DMA_SxCR_MINC /* Increment source pointer */
| DMA_SxCR_DIR_0 /* Memory to peripheral */
| DMA_SxCR_TCIE /* Transfer complete interrupt */
| DMA_SxCR_TEIE /* Transfer error interrupt */
| DMA_SxCR_EN; /* Enable transfer */
NVIC_ClearPendingIRQ(DMA1_Stream2_IRQn);
NVIC_SetPriority(DMA1_Stream2_IRQn, 10);
NVIC_EnableIRQ(DMA1_Stream2_IRQn);
/* Enable compare channel */
TIM3->CCR3 = 0;
TIM3->CCER |= TIM_CCER_CC3E;
TIM3->CR1 |= TIM_CR1_CEN;
/* Start timer */
TIM7->CR1 = TIM_CR1_CEN;
/*
* Put the calling thread in waiting status until transfer completes
*/
{
FastInterruptDisableLock dLock;
dmaWaiting = Thread::IRQgetCurrentThread();
do
{
Thread::IRQwait();
{
FastInterruptEnableLock eLock(dLock);
Thread::yield();
}
} while(dmaWaiting);
}
/* End of transfer, turn off TIM7 and DMA */
TIM7->CR1 = 0;
TIM3->CCER &= ~TIM_CCER_CC3E;
RCC->AHB1ENR &= ~RCC_AHB1ENR_DMA1EN;
RCC->APB1ENR &= ~RCC_APB1ENR_TIM7EN;
__DSB();
/* Finally, unlock tones */
FastInterruptDisableLock dLock;
tonesLocked = false;
}
bool toneGen_toneStatus()
{
/*
* Tone section is busy whenever CC3E bit in TIM3 CCER register is set.
* Lock interrupts before reading the register to avoid race conditions.
*/
FastInterruptDisableLock dLock;
return (TIM3->CCER & TIM_CCER_CC3E) ? true : false;
}

84
platform/drivers/tones/toneGenerator_MDx.h
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@ -22,12 +22,27 @@
#define TONE_GENERATOR_H
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* Tone generator for MDxx380 family, used for both CTCSS tones and user
* interface "beeps".
* This driver uses TIM3 of STM32F405 mcu in PWM mode to generate sinewaves
* using a precomputed sine table.
* Tone generator for MDx family, used primarily for CTCSS tones and user
* interface "beeps". It also provides a means to encode AFSK/4FSK data and to
* reproduce arbitrary audio samples.
*
* WARNING: this driver implements a priority mechanism between "beeps", FSK
* modulation and audio playback. A request for FSK modulation or audio playback
* always interrupts the generation of a "beep" tone and generation of "beep"
* tones is disabled when FSK modulation or audio playback is active.
*
* This driver uses the following peripherals of the STM32F405 MCU:
* - TIM3 as high-frequency PWM timebase.
* - TIM14 as timebase for CTCSS and "beeps" through a sine table.
* - TIM7 and DMA1_Stream2 for AFSK, 4FSK and playback of audio streams.
*/
/**
@ -42,9 +57,10 @@ void toneGen_terminate();
/**
* Set frequency for CTCSS tone generation.
*
* @param toneFreq: CTCSS tone frequency.
*/
void toneGen_setToneFreq(float toneFreq);
void toneGen_setToneFreq(const float toneFreq);
/**
* Activate generation of CTCSS tone.
@ -57,26 +73,58 @@ void toneGen_toneOn();
void toneGen_toneOff();
/**
* Set frequency for user interface "beep".
* @param beepFreq: frequency of "beep" tone.
* Activate generation of a "beep" tone, with a given duration.
* Audio is sent both to the speaker and to the rtx baseband IC.
*
* @param beepFreq: frequency of "beep" tone in Hz.
* @param volume: "beep" output volume, range 0 - 255.
* @param duration: tone duration in milliseconds, zero for infinite duration.
*/
void toneGen_setBeepFreq(float beepFreq);
void toneGen_beepOn(const float beepFreq, const uint8_t volume,
const uint32_t duration);
/**
* Activate generation of "beep" tone.
*/
void toneGen_beepOn();
/**
* Terminate generation of "beep" tone.
* Terminate generation of "beep" tone, irrespectively of its duration.
*/
void toneGen_beepOff();
/**
* Activate generation of "beep" tone with automatic termination after a given
* amount of time.
* @param duration: duration of "beep" tone, in milliseconds.
* Encode a given data stream using Bell 202 scheme at 1200 baud, sending the
* audio stream to both the speaker and the rtx baseband IC.
* This function blocks the execution flow until all data has been sent.
*
* @param buf: pointer to a buffer containing data to be encoded.
* @param len: length of the data buffer.
*/
void toneGen_timedBeep(uint16_t duration);
void toneGen_encodeAFSK1200(const uint8_t *buf, const size_t len);
/**
* Reproduce an audio stream, sending audio stream to both the speaker and the
* rtx baseband IC.
* This function blocks the execution flow until all data has been sent.
*
* WARNING: the underlying peripheral accepts ONLY 16 bit transfers, while the
* PWM resolution is 8 bit. Thus, the sample buffer MUST be of uint16_t elements
* and, when filling it with data, one must remember that the upper 8 bit are
* DISCARDED.
*
* @param buf: pointer to a buffer containing the audio samples.
* @param len: length of the data buffer.
* @param sampleRate: sample rate of the audio stream in samples per second.
*/
void toneGen_playAudioStream(const uint16_t *buf, const size_t len,
const uint32_t sampleRate);
/**
* Get the current status of the "beep"/AFSK/audio generator stage.
*
* @return true if the tone generator is busy.
*/
bool toneGen_toneStatus();
#ifdef __cplusplus
}
#endif
#endif /* TONE_GENERATOR_H */