IOSTM.cpp

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Digital Voice Modem - Modem Firmware
 * GPLv2 Open Source. Use is subject to license terms.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 *  Copyright (C) 2016 Jim McLaughlin, KI6ZUM
 *  Copyright (C) 2016,2017,2018 Andy Uribe, CA6JAU
 *  Copyright (C) 2017,2018 Jonathan Naylor, G4KLX
 *  Copyright (C) 2017-2018,2024 Bryan Biedenkapp, N2PLL
 *  Copyright (C) 2022 Natalie Moore
 *
 */
#include "Globals.h"
#include "IO.h"

// ---------------------------------------------------------------------------
//  Constants
// ---------------------------------------------------------------------------

#if defined(STM32F4XX) || defined(STM32F7XX)
/**
 * The STM32 factory-programmed UUID memory.
 * Three values of 32 bits each starting at this address
 * Use like this: STM32_UUID[0], STM32_UUID[1], STM32_UUID[2]
 */
#define STM32_UUID ((uint32_t *)0x1FFF7A10)

#if defined(STM32F4_PI)
/*
    Pin definitions for STM32F4 Pi Board:

    PTT      PB13   output
    COSLED   PB14   output
    LED      PB15   output
    COS      PC0    input

    DMR      PC8    output
    P25      PC9    output

    RX       PA0    analog input
    RSSI     PA7    analog input
    TX       PA4    analog output

    EXT_CLK  PA15   input
*/
#define PIN_COS GPIO_Pin_0
#define PORT_COS GPIOC
#define RCC_Per_COS RCC_AHB1Periph_GPIOC

#define PIN_PTT GPIO_Pin_13
#define PORT_PTT GPIOB
#define RCC_Per_PTT RCC_AHB1Periph_GPIOB

#define PIN_COSLED GPIO_Pin_14
#define PORT_COSLED GPIOB
#define RCC_Per_COSLED RCC_AHB1Periph_GPIOB

#define PIN_LED GPIO_Pin_15
#define PORT_LED GPIOB
#define RCC_Per_LED RCC_AHB1Periph_GPIOB

#define PIN_P25 GPIO_Pin_9
#define PORT_P25 GPIOC
#define RCC_Per_P25 RCC_AHB1Periph_GPIOC

#define PIN_DMR GPIO_Pin_8
#define PORT_DMR GPIOC
#define RCC_Per_DMR RCC_AHB1Periph_GPIOC

#define PIN_NXDN GPIO_Pin_9
#define PORT_NXDN GPIOB
#define RCC_Per_NXDN RCC_AHB1Periph_GPIOB

#define PIN_EXT_CLK GPIO_Pin_15
#define SRC_EXT_CLK GPIO_PinSource15
#define PORT_EXT_CLK GPIOA

#define PIN_RX GPIO_Pin_0
#define PIN_RX_CH ADC_Channel_0
#define PORT_RX GPIOA
#define RCC_Per_RX RCC_AHB1Periph_GPIOA

#define PIN_RSSI GPIO_Pin_7
#define PIN_RSSI_CH ADC_Channel_7
#define PORT_RSSI GPIOA
#define RCC_Per_RSSI RCC_AHB1Periph_GPIOA

#define PIN_TX GPIO_Pin_4
#define PIN_TX_CH DAC_Channel_1

#elif defined(STM32F7_PI)

/*
Pin definitions for STM32F722 Pi Board:

PTT      PB13   output
COSLED   PB14   output
LED      PB15   output
COS      PC0    input

DSTAR    PC7    output
DMR      PC8    output
YSF      PA8    output
P25      PC9    output
NXDN     PB1    output
POCSAG   PB12   output

RX       PA0    analog input
RSSI     PA7    analog input
TX       PA4    analog output

EXT_CLK  PA15   input
*/

#define PIN_COS GPIO_Pin_0
#define PORT_COS GPIOC
#define RCC_Per_COS RCC_AHB1Periph_GPIOC

#define PIN_PTT GPIO_Pin_13
#define PORT_PTT GPIOB
#define RCC_Per_PTT RCC_AHB1Periph_GPIOB

#define PIN_COSLED GPIO_Pin_14
#define PORT_COSLED GPIOB
#define RCC_Per_COSLED RCC_AHB1Periph_GPIOB

#define PIN_LED GPIO_Pin_15
#define PORT_LED GPIOB
#define RCC_Per_LED RCC_AHB1Periph_GPIOB

#define PIN_P25 GPIO_Pin_9
#define PORT_P25 GPIOC
#define RCC_Per_P25 RCC_AHB1Periph_GPIOC

#define PIN_NXDN GPIO_Pin_1
#define PORT_NXDN GPIOB
#define RCC_Per_NXDN RCC_AHB1Periph_GPIOB

#define PIN_POCSAG GPIO_Pin_12
#define PORT_POCSAG GPIOB
#define RCC_Per_POCSAG RCC_AHB1Periph_GPIOB

#define PIN_DSTAR GPIO_Pin_7
#define PORT_DSTAR GPIOC
#define RCC_Per_DSTAR RCC_AHB1Periph_GPIOC

#define PIN_DMR GPIO_Pin_8
#define PORT_DMR GPIOC
#define RCC_Per_DMR RCC_AHB1Periph_GPIOC

#define PIN_YSF GPIO_Pin_8
#define PORT_YSF GPIOA
#define RCC_Per_YSF RCC_AHB1Periph_GPIOA

#define PIN_EXT_CLK GPIO_Pin_15
#define SRC_EXT_CLK GPIO_PinSource15
#define PORT_EXT_CLK GPIOA

#define PIN_RX GPIO_Pin_0
#define PIN_RX_CH ADC_Channel_0
#define PORT_RX GPIOA
#define RCC_Per_RX RCC_AHB1Periph_GPIOA

#define PIN_RSSI GPIO_Pin_7
#define PIN_RSSI_CH ADC_Channel_7
#define PORT_RSSI GPIOA
#define RCC_Per_RSSI RCC_AHB1Periph_GPIOA

#define PIN_TX GPIO_Pin_4
#define PIN_TX_CH DAC_Channel_1

#elif defined(STM32F4_POG)
/*
    Pin definitions for STM32F4 POG Board:

    PTT      PB12   output
    COSLED   PB4    output
    LED      PB3    output
    COS      PB13   input

    DMR      PB5    output
    P25      PB8    output

    RX       PB0    analog input (ADC1_8)
    RSSI     PB1    analog input (ADC2_9)
    TX       PA4    analog output (DAC_OUT1)

    EXT_CLK  PA15   input
*/
#define PIN_COS GPIO_Pin_13
#define PORT_COS GPIOB
#define RCC_Per_COS RCC_AHB1Periph_GPIOB

#define PIN_PTT GPIO_Pin_12
#define PORT_PTT GPIOB
#define RCC_Per_PTT RCC_AHB1Periph_GPIOB

#define PIN_COSLED GPIO_Pin_4
#define PORT_COSLED GPIOB
#define RCC_Per_COSLED RCC_AHB1Periph_GPIOB

#define PIN_LED GPIO_Pin_3
#define PORT_LED GPIOB
#define RCC_Per_LED RCC_AHB1Periph_GPIOB

#define PIN_NXDN GPIO_Pin_9
#define PORT_NXDN GPIOB
#define RCC_Per_NXDN RCC_AHB1Periph_GPIOB

#define PIN_P25 GPIO_Pin_8
#define PORT_P25 GPIOB
#define RCC_Per_P25 RCC_AHB1Periph_GPIOB

#define PIN_DMR GPIO_Pin_5
#define PORT_DMR GPIOB
#define RCC_Per_DMR RCC_AHB1Periph_GPIOB

#define PIN_EXT_CLK GPIO_Pin_15
#define SRC_EXT_CLK GPIO_PinSource15
#define PORT_EXT_CLK GPIOA

#define PIN_RX GPIO_Pin_0
#define PIN_RX_CH ADC_Channel_8
#define PORT_RX GPIOB
#define RCC_Per_RX RCC_AHB1Periph_GPIOB

#define PIN_RSSI GPIO_Pin_1
#define PIN_RSSI_CH ADC_Channel_9
#define PORT_RSSI GPIOB
#define RCC_Per_RSSI RCC_AHB1Periph_GPIOB

#define PIN_TX GPIO_Pin_4
#define PIN_TX_CH DAC_Channel_1

#elif defined(STM32F4_EDA_405) || defined(STM32F4_EDA_446)
/*
    Pin definitions for STM32F4 STM32-DVM-MTR2K & STM32-DVM-MASTR3:

    PTT      PB12   output
    COSLED   PB4    output
    LED      PB3    output
    COS      PB13   input

    DMR      PB5    output
    P25      PB8    output

    RX       PB0    analog input
    RSSI     PB1    analog input
    TX       PA4    analog output

    EXT_CLK  PA15   input
*/

#define PIN_COS GPIO_Pin_13
#define PORT_COS GPIOB
#define RCC_Per_COS RCC_AHB1Periph_GPIOB

#define PIN_PTT GPIO_Pin_12
#define PORT_PTT GPIOB
#define RCC_Per_PTT RCC_AHB1Periph_GPIOB

#define PIN_COSLED GPIO_Pin_4
#define PORT_COSLED GPIOB
#define RCC_Per_COSLED RCC_AHB1Periph_GPIOB

#define PIN_LED GPIO_Pin_3
#define PORT_LED GPIOB
#define RCC_Per_LED RCC_AHB1Periph_GPIOB

#define PIN_NXDN GPIO_Pin_9
#define PORT_NXDN GPIOB
#define RCC_Per_NXDN RCC_AHB1Periph_GPIOB

#define PIN_P25 GPIO_Pin_8
#define PORT_P25 GPIOB
#define RCC_Per_P25 RCC_AHB1Periph_GPIOB

#define PIN_DMR GPIO_Pin_5
#define PORT_DMR GPIOB
#define RCC_Per_DMR RCC_AHB1Periph_GPIOB

#define PIN_EXT_CLK GPIO_Pin_15
#define SRC_EXT_CLK GPIO_PinSource15
#define PORT_EXT_CLK GPIOA

#define PIN_RX GPIO_Pin_0
#define PIN_RX_CH ADC_Channel_8
#define PORT_RX GPIOB
#define RCC_Per_RX RCC_AHB1Periph_GPIOB

#define PIN_RSSI GPIO_Pin_1
#define PIN_RSSI_CH ADC_Channel_9
#define PORT_RSSI GPIOB
#define RCC_Per_RSSI RCC_AHB1Periph_GPIOB

#define PIN_TX GPIO_Pin_4
#define PIN_TX_CH DAC_Channel_1

#elif defined(STM32F4_DVMV1)
/*
    Pin definitions for STM32F4 DVMV1 Board:

    LEDs:
    HB      PB3     output  (also known as just "LED")
    COS     PB4     output
    DMR     PB5     output
    P25     PB8     output
    NXDN    PB9     output
    FM      PC12    output
    PTT     PC13    output

    GPIO:
    PTT      PB12   output
    COS      PB13   input   (also known as INHIBIT)

    Analog:
    RX       PB0    analog input (ADC1_8)
    RSSI     PB1    analog input (ADC2_9)
    TX       PA4    analog output (DAC_OUT1)

    EXT_CLK  PA15   input
*/

// LEDs

// PIN_LED is also known as the HB LED
#define PIN_LED GPIO_Pin_3
#define PORT_LED GPIOB
#define RCC_Per_LED RCC_AHB1Periph_GPIOB

#define PIN_COSLED GPIO_Pin_4
#define PORT_COSLED GPIOB
#define RCC_Per_COSLED RCC_AHB1Periph_GPIOB

#define PIN_DMR GPIO_Pin_5
#define PORT_DMR GPIOB
#define RCC_Per_DMR RCC_AHB1Periph_GPIOB

#define PIN_P25 GPIO_Pin_8
#define PORT_P25 GPIOB
#define RCC_Per_P25 RCC_AHB1Periph_GPIOB

#define PIN_NXDN GPIO_Pin_9
#define PORT_NXDN GPIOB
#define RCC_Per_NXDN RCC_AHB1Periph_GPIOB

#define PIN_FM GPIO_Pin_12
#define PORT_FM GPIOC
#define RCC_Per_FM RCC_AHB1Periph_GPIOC

#define PIN_PTTLED GPIO_Pin_13
#define PORT_PTTLED GPIOC
#define RCC_Per_PTTLED RCC_AHB1Periph_GPIOC

// GPIO

#define PIN_PTT GPIO_Pin_12
#define PORT_PTT GPIOB
#define RCC_Per_PTT RCC_AHB1Periph_GPIOB

#define PIN_COS GPIO_Pin_13
#define PORT_COS GPIOB
#define RCC_Per_COS RCC_AHB1Periph_GPIOB

#define PIN_EXT_CLK GPIO_Pin_15
#define SRC_EXT_CLK GPIO_PinSource15
#define PORT_EXT_CLK GPIOA

// Analog

#define PIN_RX GPIO_Pin_0
#define PIN_RX_CH ADC_Channel_8
#define PORT_RX GPIOB
#define RCC_Per_RX RCC_AHB1Periph_GPIOB

#define PIN_RSSI GPIO_Pin_1
#define PIN_RSSI_CH ADC_Channel_9
#define PORT_RSSI GPIOB
#define RCC_Per_RSSI RCC_AHB1Periph_GPIOB

#define PIN_TX GPIO_Pin_4
#define PIN_TX_CH DAC_Channel_1

// SPI

#define SPI_APB_CLK_INIT RCC_APB2PeriphClockCmd
#define SPI_APB_CLK RCC_APB2Periph_SPI1

#define SPI_GPIO_AF GPIO_AF_SPI1

#define SPI_PERIPH SPI1

#define PIN_SPI_SCK GPIO_Pin_5
#define PORT_SPI_SCK GPIOA
#define RCC_Per_SCK RCC_AHB1Periph_GPIOA
#define SRC_SPI_SCK GPIO_PinSource5

#define PIN_SPI_MISO GPIO_Pin_6
#define PORT_SPI_MISO GPIOA
#define RCC_Per_MISO RCC_AHB1Periph_GPIOA
#define SRC_SPI_MISO GPIO_PinSource6

#define PIN_SPI_MOSI GPIO_Pin_7
#define PORT_SPI_MOSI GPIOA
#define RCC_Per_MOSI RCC_AHB1Periph_GPIOA
#define SRC_SPI_MOSI GPIO_PinSource7

// Digipot Chip Selects
#define PIN_CS_TXPOT GPIO_Pin_0
#define PORT_CS_TXPOT GPIOA
#define RCC_Per_TXPOT RCC_AHB1Periph_GPIOA

#define PIN_CS_RXPOT GPIO_Pin_1
#define PORT_CS_RXPOT GPIOA
#define RCC_Per_RXPOT RCC_AHB1Periph_GPIOA

#define PIN_CS_RSPOT GPIO_Pin_2
#define PORT_CS_RSPOT GPIOA
#define RCC_Per_RSPOT RCC_AHB1Periph_GPIOA

#else
#error "Only STM32F4_PI, STM32F4_POG, STM32F4_EDA_405, STM32F4_EDA_446, or STM32F4_DVMV1 is supported, others need to be defined!"
#endif

const uint16_t DC_OFFSET = 2048U;

// Sampling frequency
#define SAMP_FREQ 24000

// ---------------------------------------------------------------------------
//  Global Functions
// ---------------------------------------------------------------------------

extern "C"
{
    void TIM2_IRQHandler()
    {
        if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
        {
            TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
            io.interrupt();
        }
    }
}

// ---------------------------------------------------------------------------
//  Public Class Members
// ---------------------------------------------------------------------------

/* Hardware interrupt handler. */

void IO::interrupt()
{
    uint8_t control = MARK_NONE;
    uint16_t sample = DC_OFFSET;
    uint16_t rawRSSI = 0U;

    m_txBuffer.get(sample, control);

    // Send the value to the DAC
    DAC_SetChannel1Data(DAC_Align_12b_R, sample);

    // Read value from ADC1 and ADC2
    if ((ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) == RESET))
    {
        // shouldn't be still in reset at this point so null the sample value?
        sample = 0U;
    }
    else
    {
        sample = ADC_GetConversionValue(ADC1);
#if defined(SEND_RSSI_DATA)
        rawRSSI = ADC_GetConversionValue(ADC2);
#endif
    }

    // trigger next ADC1
    ADC_ClearFlag(ADC1, ADC_FLAG_EOC);
    ADC_SoftwareStartConv(ADC1);

    m_rxBuffer.put(sample, control);
    m_rssiBuffer.put(rawRSSI);

    m_watchdog++;
}

/* Gets the CPU type the firmware is running on. */

uint8_t IO::getCPU() const
{
    return CPU_TYPE_STM32;
}

/* Gets the unique identifier for the air interface. */

void IO::getUDID(uint8_t *buffer)
{
    ::memcpy(buffer, (void *)STM32_UUID, 12U);
}

/* */

void IO::resetMCU()
{
    DEBUG1("reset - bye-bye");

    delayInt(250);

    setLEDInt(false);
    setCOSInt(false);
    setDMRInt(false);
    setP25Int(false);
    setNXDNInt(false);

    delayInt(250);

    NVIC_SystemReset();
}

#if SPI_ENABLED
/* Sends a byte over SPI */

void IO::SPI_Write(uint8_t *bytes, uint8_t length)
{
    // Write the first byte
    SPI_I2S_SendData(SPI_PERIPH, bytes[0]);
    // DEBUG2("IO::SPI_Write() ", bytes[0]);
    if (length <= 1)
    {
        return;
    }
    // Write the remaining bytes once the TX buffer is ready
    for (int i = 1; i < length; i++)
    {
        while (SPI_I2S_GetFlagStatus(SPI_PERIPH, SPI_I2S_FLAG_BSY) == SET)
            ;
        SPI_I2S_SendData(SPI_PERIPH, bytes[i]);
        // DEBUG2("IO::SPI_Write() ", bytes[i]);
    }
    // Wait for the final byte to finish
    while (SPI_I2S_GetFlagStatus(SPI_PERIPH, SPI_I2S_FLAG_BSY) == SET)
        ;
}

/* Receives a byte from SPI */

uint16_t IO::SPI_Read()
{
    // while (SPI_I2S_GetFlagStatus(SPI_PERIPH, SPI_I2S_FLAG_RXNE) == RESET);
    uint8_t byte = SPI_I2S_ReceiveData(SPI_PERIPH);
    DEBUG2("IO::SPI_Read() ", byte);
    return byte;
}

#endif

#if DIGIPOT_ENABLED
/* Sends the digipot set value command over SPI (chip select must be set first) */

void IO::SetDigipot(uint8_t value)
{
    uint8_t bytes[2];
    bytes[0] = 0b00010001; // write command to pot 0
    bytes[1] = value;
    SPI_Write(bytes, 2);
}

/* */

void IO::SetTxDigipot(uint8_t value)
{
    // Set CS for TX pot to low
    GPIO_WriteBit(PORT_CS_TXPOT, PIN_CS_TXPOT, Bit_RESET);
    SetDigipot(value);
    GPIO_WriteBit(PORT_CS_TXPOT, PIN_CS_TXPOT, Bit_SET);
}

/* */

void IO::SetRxDigipot(uint8_t value)
{
    // Set CS for RX pot to low
    GPIO_WriteBit(PORT_CS_RXPOT, PIN_CS_RXPOT, Bit_RESET);
    SetDigipot(value);
    GPIO_WriteBit(PORT_CS_RXPOT, PIN_CS_RXPOT, Bit_SET);
}

/* */

void IO::SetRsDigipot(uint8_t value)
{
    // Set CS for TX pot to low
    GPIO_WriteBit(PORT_CS_RSPOT, PIN_CS_RSPOT, Bit_RESET);
    SetDigipot(value);
    GPIO_WriteBit(PORT_CS_RSPOT, PIN_CS_RSPOT, Bit_SET);
}

#endif

// ---------------------------------------------------------------------------
//  Private Class Members
// ---------------------------------------------------------------------------

/* Initializes hardware interrupts. */

void IO::initInt()
{
    GPIO_InitTypeDef GPIO_InitStruct;
    GPIO_StructInit(&GPIO_InitStruct);
    GPIO_InitStruct.GPIO_Speed = GPIO_Fast_Speed;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;

    // PTT pin
    RCC_AHB1PeriphClockCmd(RCC_Per_PTT, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_PTT;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_PTT, &GPIO_InitStruct);

    // COSLED pin
    RCC_AHB1PeriphClockCmd(RCC_Per_COSLED, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_COSLED;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_COSLED, &GPIO_InitStruct);

    // LED pin
    RCC_AHB1PeriphClockCmd(RCC_Per_LED, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_LED;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_LED, &GPIO_InitStruct);

    // Init the input pins PIN_COS
    RCC_AHB1PeriphClockCmd(RCC_Per_COS, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_COS;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN;
    GPIO_Init(PORT_COS, &GPIO_InitStruct);

    // DMR pin
    RCC_AHB1PeriphClockCmd(RCC_Per_DMR, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_DMR;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_DMR, &GPIO_InitStruct);

    // P25 pin
    RCC_AHB1PeriphClockCmd(RCC_Per_P25, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_P25;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_P25, &GPIO_InitStruct);

    // NXDN pin
    RCC_AHB1PeriphClockCmd(RCC_Per_NXDN, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_NXDN;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_NXDN, &GPIO_InitStruct);

    // DVM-V1 LEDs
    #if defined(STM32F4_DVMV1)
    
    // FM pin (never actually used since we don't do FM)
    RCC_AHB1PeriphClockCmd(RCC_Per_FM, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_FM;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_FM, &GPIO_InitStruct);

    // PTT LED pin (separate from the actual PTT pin for ESD reasons)
    RCC_AHB1PeriphClockCmd(RCC_Per_PTTLED, ENABLE);
    GPIO_InitStruct.GPIO_Pin = PIN_PTTLED;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_Init(PORT_PTTLED, &GPIO_InitStruct);
    
    #endif

#if SPI_ENABLED
    // Init SPI Clock
    SPI_APB_CLK_INIT(SPI_APB_CLK, ENABLE);

    // Init AHB1 GPIO CLocks
    RCC_AHB1PeriphClockCmd(RCC_Per_SCK | RCC_Per_MISO | RCC_Per_MOSI | RCC_Per_TXPOT | RCC_Per_RXPOT | RCC_Per_RSPOT, ENABLE);

    // Init Alternate Functions
    GPIO_PinAFConfig(PORT_SPI_SCK, SRC_SPI_SCK, SPI_GPIO_AF);
    GPIO_PinAFConfig(PORT_SPI_MISO, SRC_SPI_MISO, SPI_GPIO_AF);
    GPIO_PinAFConfig(PORT_SPI_MOSI, SRC_SPI_MOSI, SPI_GPIO_AF);

    // Init GPIO Pins
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Low_Speed;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;

    // Init SCK
    GPIO_InitStruct.GPIO_Pin = PIN_SPI_SCK;
    GPIO_Init(PORT_SPI_SCK, &GPIO_InitStruct);

    // Init MOSI
    GPIO_InitStruct.GPIO_Pin = PIN_SPI_MOSI;
    GPIO_Init(PORT_SPI_MOSI, &GPIO_InitStruct);

    // Init MISO
    GPIO_InitStruct.GPIO_Pin = PIN_SPI_MISO;
    GPIO_Init(PORT_SPI_MISO, &GPIO_InitStruct);

    // Init CS Pins
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;

    // Init CS for TX Pot
    GPIO_InitStruct.GPIO_Pin = PIN_CS_TXPOT;
    GPIO_Init(PORT_CS_TXPOT, &GPIO_InitStruct);

    // Init CS for RX Pot
    GPIO_InitStruct.GPIO_Pin = PIN_CS_RXPOT;
    GPIO_Init(PORT_CS_RXPOT, &GPIO_InitStruct);

    // Init CS for RSSI Pot
    GPIO_InitStruct.GPIO_Pin = PIN_CS_RSPOT;
    GPIO_Init(PORT_CS_RSPOT, &GPIO_InitStruct);

#endif
}

/* Starts hardware interrupts. */

void IO::startInt()
{
    if ((ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) != RESET))
        io.interrupt();

    // Init the ADC
    GPIO_InitTypeDef GPIO_InitStruct;
    ADC_InitTypeDef ADC_InitStructure;
    ADC_CommonInitTypeDef ADC_CommonInitStructure;

    GPIO_StructInit(&GPIO_InitStruct);
    ADC_CommonStructInit(&ADC_CommonInitStructure);
    ADC_StructInit(&ADC_InitStructure);

    // Enable ADC1 clock
    RCC_AHB1PeriphClockCmd(RCC_Per_RX, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
    // Enable ADC1 GPIO
    GPIO_InitStruct.GPIO_Pin = PIN_RX;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(PORT_RX, &GPIO_InitStruct);
#if defined(SEND_RSSI_DATA)
    // Enable ADC2 clock
    RCC_AHB1PeriphClockCmd(RCC_Per_RSSI, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC2, ENABLE);
    // Enable ADC2 GPIO
    GPIO_InitStruct.GPIO_Pin = PIN_RSSI;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(PORT_RSSI, &GPIO_InitStruct);
#endif
    // Init ADCs in dual mode (RSSI), div clock by two
#if defined(SEND_RSSI_DATA)
    ADC_CommonInitStructure.ADC_Mode = ADC_DualMode_RegSimult;
#else
    ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
#endif
    ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
    ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
    ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
    ADC_CommonInit(&ADC_CommonInitStructure);

    // Init ADC1 and ADC2: 12bit, single-conversion
    ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanConvMode = DISABLE;
    ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
    ADC_InitStructure.ADC_ExternalTrigConvEdge = 0;
    ADC_InitStructure.ADC_ExternalTrigConv = 0;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfConversion = 1;

    ADC_Init(ADC1, &ADC_InitStructure);

    ADC_EOCOnEachRegularChannelCmd(ADC1, ENABLE);
    ADC_RegularChannelConfig(ADC1, PIN_RX_CH, 1, ADC_SampleTime_3Cycles);

    // Enable ADC1
    ADC_Cmd(ADC1, ENABLE);
#if defined(SEND_RSSI_DATA)
    ADC_Init(ADC2, &ADC_InitStructure);

    ADC_EOCOnEachRegularChannelCmd(ADC2, ENABLE);
    ADC_RegularChannelConfig(ADC2, PIN_RSSI_CH, 1, ADC_SampleTime_3Cycles);

    // Enable ADC2
    ADC_Cmd(ADC2, ENABLE);
#endif
    // Init the DAC
    DAC_InitTypeDef DAC_InitStructure;

    GPIO_StructInit(&GPIO_InitStruct);
    DAC_StructInit(&DAC_InitStructure);

    // GPIOA clock enable
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    // DAC Periph clock enable
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);

    // GPIO CONFIGURATION of DAC Pin
    GPIO_InitStruct.GPIO_Pin = PIN_TX;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;
    DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
    DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
    DAC_Init(PIN_TX_CH, &DAC_InitStructure);
    DAC_Cmd(PIN_TX_CH, ENABLE);

    // Init the timer
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

#if defined(EXTERNAL_OSC) && !(defined(STM32F4_PI))
    // Configure a GPIO as external TIM2 clock source
    GPIO_PinAFConfig(PORT_EXT_CLK, SRC_EXT_CLK, GPIO_AF_TIM2);
    GPIO_InitStruct.GPIO_Pin = PIN_EXT_CLK;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_Init(PORT_EXT_CLK, &GPIO_InitStruct);
#endif

    TIM_TimeBaseInitTypeDef timerInitStructure;
    TIM_TimeBaseStructInit(&timerInitStructure);

    // TIM2 output frequency
#if defined(EXTERNAL_OSC) && !(defined(STM32F4_PI))
    timerInitStructure.TIM_Prescaler = (uint16_t)((EXTERNAL_OSC / (2 * SAMP_FREQ)) - 1);
    timerInitStructure.TIM_Period = 1;
#else
    timerInitStructure.TIM_Prescaler = (uint16_t)((SystemCoreClock / (6 * SAMP_FREQ)) - 1);
    timerInitStructure.TIM_Period = 2;
#endif

    timerInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    timerInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    timerInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &timerInitStructure);

#if defined(EXTERNAL_OSC) && !(defined(STM32F4_PI))
    // Enable external clock
    TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0x00);
#else
    // Enable internal clock
    TIM_InternalClockConfig(TIM2);
#endif

    // Enable TIM2
    TIM_Cmd(TIM2, ENABLE);
    // Enable TIM2 interrupt
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);

    NVIC_InitTypeDef nvicStructure;
    nvicStructure.NVIC_IRQChannel = TIM2_IRQn;
    nvicStructure.NVIC_IRQChannelPreemptionPriority = 0;
    nvicStructure.NVIC_IRQChannelSubPriority = 1;
    nvicStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&nvicStructure);

#if defined(SPI_ENABLED)
    SPI_InitTypeDef SPI_Initstruct;
    SPI_Initstruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
    SPI_Initstruct.SPI_Mode = SPI_Mode_Master;
    SPI_Initstruct.SPI_DataSize = SPI_DataSize_8b;
    // MCP41010 uses rising edge clock, low clock idle (0,0)
    SPI_Initstruct.SPI_CPOL = SPI_CPOL_Low;
    SPI_Initstruct.SPI_CPHA = SPI_CPHA_1Edge;
    SPI_Initstruct.SPI_NSS = SPI_NSS_Soft;
    SPI_Initstruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_64;
    SPI_Initstruct.SPI_FirstBit = SPI_FirstBit_MSB;
    SPI_Init(SPI_PERIPH, &SPI_Initstruct);
    SPI_Cmd(SPI_PERIPH, ENABLE);
#endif

    GPIO_ResetBits(PORT_COSLED, PIN_COSLED);
    GPIO_SetBits(PORT_LED, PIN_LED);
}

/*  */

bool IO::getCOSInt()
{
    return GPIO_ReadInputDataBit(PORT_COS, PIN_COS) == Bit_SET;
}

/*  */

void IO::setLEDInt(bool on)
{
    GPIO_WriteBit(PORT_LED, PIN_LED, on ? Bit_SET : Bit_RESET);
}

/*  */

void IO::setPTTInt(bool on)
{
    GPIO_WriteBit(PORT_PTT, PIN_PTT, on ? Bit_SET : Bit_RESET);
    #if defined(STM32F4_DVMV1)
    // We tie the PTT LED to PTT on the V1
    setPTTLEDInt(on);
    #endif
}

/*  */

void IO::setCOSInt(bool on)
{
    GPIO_WriteBit(PORT_COSLED, PIN_COSLED, on ? Bit_SET : Bit_RESET);
}

/*  */

void IO::setDMRInt(bool on)
{
    GPIO_WriteBit(PORT_DMR, PIN_DMR, on ? Bit_SET : Bit_RESET);
}

/*  */

void IO::setP25Int(bool on)
{
    GPIO_WriteBit(PORT_P25, PIN_P25, on ? Bit_SET : Bit_RESET);
}

/*  */

void IO::setNXDNInt(bool on)
{
    GPIO_WriteBit(PORT_NXDN, PIN_NXDN, on ? Bit_SET : Bit_RESET);
}

/*  */

#if defined(STM32F4_DVMV1)

void IO::setFMInt(bool on)
{
    GPIO_WriteBit(PORT_FM, PIN_FM, on ? Bit_SET : Bit_RESET);
}

void IO::setPTTLEDInt(bool on)
{
    GPIO_WriteBit(PORT_PTTLED, PIN_PTTLED, on ? Bit_SET : Bit_RESET);
}

#endif

void IO::delayInt(unsigned int dly)
{
    unsigned int loopsPerMillisecond = (SystemCoreClock / 1000) / 3;

    for (; dly > 0; dly--)
    {
        asm volatile // this routine waits (approximately) one millisecond
            (
                "mov r3, %[loopsPerMillisecond] \n\t" // load the initial loop counter
                "loop: \n\t"
                "subs r3, #1 \n\t"
                "bne loop \n\t"

                :                                                // empty output list
                : [loopsPerMillisecond] "r"(loopsPerMillisecond) // input to the asm routine
                : "r3", "cc"                                     // clobber list
            );
    }
}

/*  */

void *IO::txThreadHelper(void *arg)
{
    return NULL;
}

/*  */

void IO::interruptRx()
{
    /* stub */
}

/*  */

void *IO::rxThreadHelper(void *arg)
{
    return NULL;
}

#endif // defined(STM32F4XX)