VLM5030.cc

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/*
    vlm5030.c

    VLM5030 emulator

    Written by Tatsuyuki Satoh
    Based on TMS5220 simulator (tms5220.c)

  note:
    memory read cycle(==sampling rate) = 122.9u(440clock)
    interpolator (LC8109 = 2.5ms)      = 20 * samples(125us)
    frame time (20ms)                  =  4 * interpolator
    9bit DAC is composed of 5bit Physical and 3bitPWM.

  todo:
    Noise Generator circuit without 'rand()' function.

----------- command format (Analytical result) ----------

1)end of speech (8bit)
:00000011:

2)silent some frame (8bit)
:????SS01:

SS : number of silent frames
   00 = 2 frame
   01 = 4 frame
   10 = 6 frame
   11 = 8 frame

3)-speech frame (48bit)
function:   6th  :  5th   :   4th  :   3rd  :   2nd  : 1st    :
end     :   ---  :  ---   :   ---  :   ---  :   ---  :00000011:
silent  :   ---  :  ---   :   ---  :   ---  :   ---  :0000SS01:
speech  :11111122:22233334:44455566:67778889:99AAAEEE:EEPPPPP0:

EEEEE  : energy : volume 0=off,0x1f=max
PPPPP  : pitch  : 0=noize , 1=fast,0x1f=slow
111111 : K1     : 48=off
22222  : K2     : 0=off,1=+min,0x0f=+max,0x10=off,0x11=+max,0x1f=-min
                : 16 == special function??
3333   : K3     : 0=off,1=+min,0x07=+max,0x08=-max,0x0f=-min
4444   : K4     :
555    : K5     : 0=off,1=+min,0x03=+max,0x04=-max,0x07=-min
666    : K6     :
777    : K7     :
888    : K8     :
999    : K9     :
AAA    : K10    :

 ---------- chirp table information ----------

DAC PWM cycle == 88system clock , (11clock x 8 pattern) = 40.6KHz
one chirp     == 5 x PWM cycle == 440systemclock(8,136Hz)

chirp  0   : volume 10- 8 : with filter
chirp  1   : volume  8- 6 : with filter
chirp  2   : volume  6- 4 : with filter
chirp  3   : volume   4   : no filter ??
chirp  4- 5: volume  4- 2 : with filter
chirp  6-11: volume  2- 0 : with filter
chirp 12-..: vokume   0   : silent

 ---------- digial output information ----------
 when ME pin = high , some status output to A0..15 pins

  A0..8   : DAC output value (abs)
  A9      : DAC sign flag , L=minus,H=Plus
  A10     : energy reload flag (pitch pulse)
  A11..15 : unknown

  [DAC output value(signed 6bit)] = A9 ? A0..8 : -(A0..8)

*/

#include "VLM5030.hh"
#include "DeviceConfig.hh"
#include "XMLElement.hh"
#include "FileOperations.hh"
#include "Math.hh"
#include "cstd.hh"
#include "serialize.hh"
#include "random.hh"
#include "ranges.hh"
#include <cmath>
#include <cstring>

namespace openmsx {


// interpolator per frame
constexpr int FR_SIZE = 4;
// samples per interpolator
constexpr int IP_SIZE_SLOWER = 240 / FR_SIZE;
constexpr int IP_SIZE_SLOW   = 200 / FR_SIZE;
constexpr int IP_SIZE_NORMAL = 160 / FR_SIZE;
constexpr int IP_SIZE_FAST   = 120 / FR_SIZE;
constexpr int IP_SIZE_FASTER =  80 / FR_SIZE;

// phase value
enum {
        PH_RESET,
        PH_IDLE,
        PH_SETUP,
        PH_WAIT,
        PH_RUN,
        PH_STOP,
        PH_END
};

// speed parameter
// SPC SPB SPA
//  1   0   1  more slow (05h)     : 42ms   (150%) : 60sample
//  1   1   x  slow      (06h,07h) : 34ms   (125%) : 50sample
//  x   0   0  normal    (00h,04h) : 25.6ms (100%) : 40samplme
//  0   0   1  fast      (01h)     : 20.2ms  (75%) : 30sample
//  0   1   x  more fast (02h,03h) : 12.2ms  (50%) : 20sample
constexpr int VLM5030_speed_table[8] =
{
        IP_SIZE_NORMAL,
        IP_SIZE_FAST,
        IP_SIZE_FASTER,
        IP_SIZE_FASTER,
        IP_SIZE_NORMAL,
        IP_SIZE_SLOWER,
        IP_SIZE_SLOW,
        IP_SIZE_SLOW
};

// ROM Tables

// This is the energy lookup table

// sampled from real chip
static word energytable[0x20] =
{
          0,  2,  4,  6, 10, 12, 14, 18, //  0-7
         22, 26, 30, 34, 38, 44, 48, 54, //  8-15
         62, 68, 76, 84, 94,102,114,124, // 16-23
        136,150,164,178,196,214,232,254  // 24-31
};

// This is the pitch lookup table
constexpr byte pitchtable [0x20] =
{
        1,                               // 0     : random mode
        22,                              // 1     : start=22
        23, 24, 25, 26, 27, 28, 29, 30,  //  2- 9 : 1step
        32, 34, 36, 38, 40, 42, 44, 46,  // 10-17 : 2step
        50, 54, 58, 62, 66, 70, 74, 78,  // 18-25 : 4step
        86, 94, 102,110,118,126          // 26-31 : 8step
};

constexpr int16_t K1_table[] = {
        -24898,  -25672,  -26446,  -27091,  -27736,  -28252,  -28768,  -29155,
        -29542,  -29929,  -30316,  -30574,  -30832,  -30961,  -31219,  -31348,
        -31606,  -31735,  -31864,  -31864,  -31993,  -32122,  -32122,  -32251,
        -32251,  -32380,  -32380,  -32380,  -32509,  -32509,  -32509,  -32509,
         24898,   23995,   22963,   21931,   20770,   19480,   18061,   16642,
         15093,   13416,   11610,    9804,    7998,    6063,    3999,    1935,
             0,   -1935,   -3999,   -6063,   -7998,   -9804,  -11610,  -13416,
        -15093,  -16642,  -18061,  -19480,  -20770,  -21931,  -22963,  -23995
};
constexpr int16_t K2_table[] = {
             0,   -3096,   -6321,   -9417,  -12513,  -15351,  -18061,  -20770,
        -23092,  -25285,  -27220,  -28897,  -30187,  -31348,  -32122,  -32638,
             0,   32638,   32122,   31348,   30187,   28897,   27220,   25285,
         23092,   20770,   18061,   15351,   12513,    9417,    6321,    3096
};
constexpr int16_t K3_table[] = {
            0,   -3999,   -8127,  -12255,  -16384,  -20383,  -24511,  -28639,
        32638,   28639,   24511,   20383,   16254,   12255,    8127,    3999
};
constexpr int16_t K5_table[] = {
        0,   -8127,  -16384,  -24511,   32638,   24511,   16254,    8127
};

int VLM5030::getBits(unsigned sbit, unsigned bits)
{
        unsigned offset = address + (sbit / 8);
        unsigned data = rom[(offset + 0) & address_mask] +
                        rom[(offset + 1) & address_mask] * 256;
        data >>= (sbit & 7);
        data &= (0xFF >> (8 - bits));
        return data;
}

// get next frame
int VLM5030::parseFrame()
{
        // remember previous frame
        old_energy = new_energy;
        old_pitch = new_pitch;
        for (int i = 0; i <= 9; ++i) {
                old_k[i] = new_k[i];
        }
        // command byte check
        byte cmd = rom[address & address_mask];
        if (cmd & 0x01) {
                // extend frame
                new_energy = new_pitch = 0;
                ranges::fill(new_k, 0);
                ++address;
                if (cmd & 0x02) {
                        // end of speech
                        return 0;
                } else {
                        // silent frame
                        int nums = ((cmd >> 2) + 1) * 2;
                        return nums * FR_SIZE;
                }
        }
        // pitch
        new_pitch  = (pitchtable[getBits(1, 5)] + pitch_offset) & 0xff;
        // energy
        new_energy = energytable[getBits(6, 5)];

        // 10 K's
        new_k[9] = K5_table[getBits(11, 3)];
        new_k[8] = K5_table[getBits(14, 3)];
        new_k[7] = K5_table[getBits(17, 3)];
        new_k[6] = K5_table[getBits(20, 3)];
        new_k[5] = K5_table[getBits(23, 3)];
        new_k[4] = K5_table[getBits(26, 3)];
        new_k[3] = K3_table[getBits(29, 4)];
        new_k[2] = K3_table[getBits(33, 4)];
        new_k[1] = K2_table[getBits(37, 5)];
        new_k[0] = K1_table[getBits(42, 6)];

        address += 6;
        return FR_SIZE;
}

// decode and buffering data
void VLM5030::generateChannels(float** bufs, unsigned num)
{
        // Single channel device: replace content of bufs[0] (not add to it).
        if (phase == PH_IDLE) {
                bufs[0] = nullptr;
                return;
        }

        int buf_count = 0;

        // running
        if (phase == PH_RUN || phase == PH_STOP) {
                // playing speech
                while (num > 0) {
                        int current_val;
                        // check new interpolator or new frame
                        if (sample_count == 0) {
                                if (phase == PH_STOP) {
                                        phase = PH_END;
                                        sample_count = 1;
                                        goto phase_stop; // continue to end phase
                                }
                                sample_count = frame_size;
                                // interpolator changes
                                if (interp_count == 0) {
                                        // change to new frame
                                        interp_count = parseFrame(); // with change phase
                                        if (interp_count == 0 ) {
                                                // end mark found
                                                interp_count = FR_SIZE;
                                                sample_count = frame_size; // end -> stop time
                                                phase = PH_STOP;
                                        }
                                        // Set old target as new start of frame
                                        current_energy = old_energy;
                                        current_pitch = old_pitch;
                                        for (int i = 0; i <= 9; ++i) {
                                                current_k[i] = old_k[i];
                                        }
                                        // is this a zero energy frame?
                                        if (current_energy == 0) {
                                                target_energy = 0;
                                                target_pitch = current_pitch;
                                                for (int i = 0; i <= 9; ++i) {
                                                        target_k[i] = current_k[i];
                                                }
                                        } else {
                                                // normal frame
                                                target_energy = new_energy;
                                                target_pitch = new_pitch;
                                                for (int i = 0; i <= 9; ++i) {
                                                        target_k[i] = new_k[i];
                                                }
                                        }
                                }
                                // next interpolator
                                // Update values based on step values 25%, 50%, 75%, 100%
                                interp_count -= interp_step;
                                // 3,2,1,0 -> 1,2,3,4
                                int interp_effect = FR_SIZE - (interp_count % FR_SIZE);
                                current_energy = old_energy + (target_energy - old_energy) * interp_effect / FR_SIZE;
                                if (old_pitch > 1) {
                                        current_pitch = old_pitch + (target_pitch - old_pitch) * interp_effect / FR_SIZE;
                                }
                                for (int i = 0; i <= 9; ++i)
                                        current_k[i] = old_k[i] + (target_k[i] - old_k[i]) * interp_effect / FR_SIZE;
                        }
                        // calcrate digital filter
                        if (old_energy == 0) {
                                // generate silent samples here
                                current_val = 0x00;
                        } else if (old_pitch <= 1) {
                                // generate unvoiced samples here
                                current_val = random_bool() ?  int(current_energy)
                                                            : -int(current_energy);
                        } else {
                                // generate voiced samples here
                                current_val = (pitch_count == 0) ? current_energy : 0;
                        }

                        // Lattice filter here
                        int u[11];
                        u[10] = current_val;
                        for (int i = 9; i >= 0; --i) {
                                u[i] = u[i + 1] - ((current_k[i] * x[i]) / 32768);
                        }
                        for (int i = 9; i >= 1; --i) {
                                x[i] = x[i - 1] + ((current_k[i - 1] * u[i - 1]) / 32768);
                        }
                        x[0] = u[0];

                        // clipping, buffering
                        bufs[0][buf_count] = Math::clip<-511, 511>(u[0]);
                        ++buf_count;
                        --sample_count;
                        ++pitch_count;
                        if (pitch_count >= current_pitch) {
                                pitch_count = 0;
                        }
                        --num;
                }
        // return;
        }
phase_stop:
        switch (phase) {
        case PH_SETUP:
                if (sample_count <= num) {
                        sample_count = 0;
                        // pin_BSY = true;
                        phase = PH_WAIT;
                } else {
                        sample_count -= num;
                }
                break;
        case PH_END:
                if (sample_count <= num) {
                        sample_count = 0;
                        pin_BSY = false;
                        phase = PH_IDLE;
                } else {
                        sample_count -= num;
                }
        }
        // silent buffering
        while (num > 0) {
                bufs[0][buf_count++] = 0;
                --num;
        }
}

float VLM5030::getAmplificationFactorImpl() const
{
        return 1.0f / (1 << 9);
}

// setup parameteroption when RST=H
void VLM5030::setupParameter(byte param)
{
        // latch parameter value
        parameter = param;

        // bit 0,1 : 4800bps / 9600bps , interporator step
        if (param & 2) {          // bit 1 = 1 , 9600bps
                interp_step = 4;  // 9600bps : no interporator
        } else if (param & 1) {   // bit1 = 0 & bit0 = 1 , 4800bps
                interp_step = 2;  // 4800bps : 2 interporator
        } else {                  // bit1 = bit0 = 0 : 2400bps
                interp_step = 1;  // 2400bps : 4 interporator
        }

        // bit 3,4,5 : speed (frame size)
        frame_size = VLM5030_speed_table[(param >> 3) & 7];

        // bit 6,7 : low / high pitch
        if (param & 0x80) {        // bit7=1 , high pitch
                pitch_offset = -8;
        } else if (param & 0x40) { // bit6=1 , low pitch
                pitch_offset = 8;
        } else {
                pitch_offset = 0;
        }
}

void VLM5030::reset()
{
        phase = PH_RESET;
        address = 0;
        vcu_addr_h = 0;
        pin_BSY = false;

        old_energy = old_pitch = 0;
        new_energy = new_pitch = 0;
        current_energy = current_pitch = 0;
        target_energy = target_pitch = 0;
        memset(old_k, 0, sizeof(old_k));
        memset(new_k, 0, sizeof(new_k));
        memset(current_k, 0, sizeof(current_k));
        memset(target_k, 0, sizeof(target_k));
        interp_count = sample_count = pitch_count = 0;
        memset(x, 0, sizeof(x));
        // reset parameters
        setupParameter(0x00);
}

// get BSY pin level
bool VLM5030::getBSY(EmuTime::param time) const
{
        const_cast<VLM5030*>(this)->updateStream(time);
        return pin_BSY;
}

// latch control data
void VLM5030::writeData(byte data)
{
        latch_data = data;
}

void VLM5030::writeControl(byte data, EmuTime::param time)
{
        updateStream(time);
        setRST((data & 0x01) != 0);
        setVCU((data & 0x04) != 0);
        setST ((data & 0x02) != 0);
}

// set RST pin level : reset / set table address A8-A15
void VLM5030::setRST(bool pin)
{
        if (pin_RST) {
                if (!pin) { // H -> L : latch parameters
                        pin_RST = false;
                        setupParameter(latch_data);
                }
        } else {
                if (pin) { // L -> H : reset chip
                        pin_RST = true;
                        if (pin_BSY) {
                                reset();
                        }
                }
        }
}

// set VCU pin level : ?? unknown
void VLM5030::setVCU(bool pin)
{
        // direct mode / indirect mode
        pin_VCU = pin;
}

// set ST pin level  : set table address A0-A7 / start speech
void VLM5030::setST(bool pin)
{
        if (pin_ST == pin) {
                // pin level unchanged
                return;
        }
        if (!pin) {
                // H -> L
                pin_ST = false;
                if (pin_VCU) {
                        // direct access mode & address High
                        vcu_addr_h = (int(latch_data) << 8) + 0x01;
                } else {
                        // check access mode
                        if (vcu_addr_h) {
                                // direct access mode
                                address = (vcu_addr_h & 0xff00) + latch_data;
                                vcu_addr_h = 0;
                        } else {
                                // indirect access mode
                                int table = (latch_data & 0xfe) + ((int(latch_data) & 1) << 8);
                                address = ((rom[(table + 0) & address_mask]) << 8) |
                                            rom[(table + 1) & address_mask];
                        }
                        // reset process status
                        sample_count = frame_size;
                        interp_count = FR_SIZE;
                        // clear filter
                        // start after 3 sampling cycle
                        phase = PH_RUN;
                }
        } else {
                // L -> H
                pin_ST = true;
                // setup speech, BSY on after 30ms?
                phase = PH_SETUP;
                sample_count = 1; // wait time for busy on
                pin_BSY = true;
        }
}


static XMLElement getRomConfig(const std::string& name, const std::string& romFilename)
{
        XMLElement voiceROMconfig(name);
        voiceROMconfig.addAttribute("id", "name");
        auto& romElement = voiceROMconfig.addChild("rom");
        romElement.addChild( // load by sha1sum
                "sha1", "4f36d139ee4baa7d5980f765de9895570ee05f40");
        romElement.addChild( // load by predefined filename in software rom's dir
                "filename", strCat(FileOperations::stripExtension(romFilename), "_voice.rom"));
        romElement.addChild( // or hardcoded filename in ditto dir
                "filename", "keyboardmaster/voice.rom");
        return voiceROMconfig;
}

constexpr auto INPUT_RATE = unsigned(cstd::round(3579545 / 440.0));

VLM5030::VLM5030(const std::string& name_, const std::string& desc,
                 const std::string& romFilename, const DeviceConfig& config)
        : ResampledSoundDevice(config.getMotherBoard(), name_, desc, 1, INPUT_RATE, false)
        , rom(name_ + " ROM", "rom", DeviceConfig(config, getRomConfig(name_, romFilename)))
{
        // reset input pins
        pin_RST = pin_ST = pin_VCU = false;
        latch_data = 0;

        reset();
        phase = PH_IDLE;

        address_mask = rom.getSize() - 1;

        registerSound(config);
}

VLM5030::~VLM5030()
{
        unregisterSound();
}

template<typename Archive>
void VLM5030::serialize(Archive& ar, unsigned /*version*/)
{
        ar.serialize("address_mask",   address_mask,
                     "frame_size",     frame_size,
                     "pitch_offset",   pitch_offset,
                     "current_energy", current_energy,
                     "current_pitch",  current_pitch,
                     "current_k",      current_k,
                     "x",              x,
                     "address",        address,
                     "vcu_addr_h",     vcu_addr_h,
                     "old_k",          old_k,
                     "new_k",          new_k,
                     "target_k",       target_k,
                     "old_energy",     old_energy,
                     "new_energy",     new_energy,
                     "target_energy",  target_energy,
                     "old_pitch",      old_pitch,
                     "new_pitch",      new_pitch,
                     "target_pitch",   target_pitch,
                     "interp_step",    interp_step,
                     "interp_count",   interp_count,
                     "sample_count",   sample_count,
                     "pitch_count",    pitch_count,
                     "latch_data",     latch_data,
                     "parameter",      parameter,
                     "phase",          phase,
                     "pin_BSY",        pin_BSY,
                     "pin_ST",         pin_ST,
                     "pin_VCU",        pin_VCU,
                     "pin_RST",        pin_RST);
}

INSTANTIATE_SERIALIZE_METHODS(VLM5030);

} // namespace openmsx