saleae-iec-analyser/source/C64SerialAnalyzer.cpp

#include "C64SerialAnalyzer.h"
#include "C64SerialAnalyzerSettings.h"
#include <AnalyzerChannelData.h>

C64SerialAnalyzer::C64SerialAnalyzer()
    : Analyzer2(), mSettings(new C64SerialAnalyzerSettings()),
      mSimulationInitilized(false) {
    SetAnalyzerSettings(mSettings.get());
}

C64SerialAnalyzer::~C64SerialAnalyzer() { KillThread(); }

void C64SerialAnalyzer::SetupResults() {
    mResults.reset(new C64SerialAnalyzerResults(this, mSettings.get()));
    SetAnalyzerResults(mResults.get());
    mResults->AddChannelBubblesWillAppearOn(mSettings->mDataChannel);
}

U64 C64SerialAnalyzer::AdvanceTo(U64 sample) {
    mData->AdvanceToAbsPosition(sample);
    mClock->AdvanceToAbsPosition(sample);
    //mAttention->AdvanceToAbsPosition(sample);

    return sample;
}

bool C64SerialAnalyzer::ReceiveByte() {
    // Advance until both clock and data lines are asserted.
    while (mData->GetBitState() == BIT_LOW ||
           mClock->GetBitState() == BIT_LOW) {
        AdvanceTo(std::min(mData->GetSampleOfNextEdge(),
                           mClock->GetSampleOfNextEdge()));
    }

    bool eoi = mData->GetSampleOfNextEdge() < mClock->GetSampleOfNextEdge();
    if (eoi) {
        // An EOI happened, go back to idle after finishing.
        mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::X,
                            mSettings->mClockChannel);
    }

    mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::Start,
                        mSettings->mDataChannel);
    U64 start_sample = AdvanceTo(mClock->GetSampleOfNextEdge());

    // Receive a byte
    U8 byte = 0;
    for (int i = 0; i < 8; i++) {
        AdvanceTo(mClock->GetSampleOfNextEdge());
        mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::Dot,
                            mSettings->mDataChannel);
        mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::UpArrow,
                            mSettings->mClockChannel);

        byte |= mData->GetBitState() << i;

        AdvanceTo(mClock->GetSampleOfNextEdge());
        mResults->AddMarker(mClock->GetSampleNumber(),
                            AnalyzerResults::DownArrow,
                            mSettings->mClockChannel);
    }

    // We have a byte to save
    Frame frame;
    frame.mData1 = byte;
    frame.mType = static_cast<U8>(mState);
    frame.mStartingSampleInclusive = start_sample;
    frame.mEndingSampleInclusive = mData->GetSampleNumber();

    mResults->AddFrame(frame);
    mResults->CommitResults();
    ReportProgress(frame.mEndingSampleInclusive);

    // Wait until data is high and back down.
    if (mData->GetBitState() == BIT_LOW) {
        AdvanceTo(mData->GetSampleOfNextEdge());
    }
    AdvanceTo(mData->GetSampleOfNextEdge());

    mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::Stop,
                        mSettings->mDataChannel);

    return eoi;
}

enum class FrameType {
    Attention,
    Talking,
};

void C64SerialAnalyzer::Update() {
    mResults->AddMarker(mClock->GetSampleNumber(), AnalyzerResults::Dot,
                        mSettings->mAttentionChannel);

    if (mState == State::Idle) {
        // Advance until both clock and data lines are asserted.
        while (mData->GetBitState() == BIT_HIGH ||
               mClock->GetBitState() == BIT_HIGH) {
            AdvanceTo(std::min(mData->GetSampleOfNextEdge(),
                               mClock->GetSampleOfNextEdge()));
        }

        // Check if attention was asserted.
        BitState old_attention = mAttention->GetBitState();
        mAttention->AdvanceToAbsPosition(mClock->GetSampleOfNextEdge());
        BitState new_attention = mAttention->GetBitState();

        if (new_attention == BIT_LOW) {
            mState = State::Attention;
        } else if (old_attention == BIT_LOW) {
            // If attention was low but is now high, check if talking continues.
            if (mData->GetSampleOfNextEdge() > mClock->GetSampleOfNextEdge()) {
                mState = State::Talking;
            } else {
                AdvanceTo(mAttention->GetSampleNumber());
            }
        } else {
            mState = State::Talking;
        }
    } else if (mState == State::Attention) {
        ReceiveByte();
        mState = State::Idle;
    } else if (mState == State::Talking) {
        bool eoi = ReceiveByte();

        if (eoi) {
            mState = State::Idle;
        }
    } else if (mState == State::TurnAround) {
    }
}

void C64SerialAnalyzer::WorkerThread() {
    mSampleRateHz = GetSampleRate();

    mAttention = GetAnalyzerChannelData(mSettings->mAttentionChannel);
    mData = GetAnalyzerChannelData(mSettings->mDataChannel);
    mClock = GetAnalyzerChannelData(mSettings->mClockChannel);

    mState = State::Idle;
    while (true) {
        Update();
        CheckIfThreadShouldExit();
    }
}

bool C64SerialAnalyzer::NeedsRerun() { return false; }

U32 C64SerialAnalyzer::GenerateSimulationData(
    U64 minimum_sample_index, U32 device_sample_rate,
    SimulationChannelDescriptor **simulation_channels) {
    if (mSimulationInitilized == false) {
        mSimulationDataGenerator.Initialize(GetSimulationSampleRate(),
                                            mSettings.get());
        mSimulationInitilized = true;
    }

    return mSimulationDataGenerator.GenerateSimulationData(
        minimum_sample_index, device_sample_rate, simulation_channels);
}

U32 C64SerialAnalyzer::GetMinimumSampleRateHz() {
    // return mSettings->mBitRate * 4;
    return 4000000;
}

const char *C64SerialAnalyzer::GetAnalyzerName() const { return "C64 Serial"; }

const char *GetAnalyzerName() { return "C64 Serial"; }

Analyzer *CreateAnalyzer() { return new C64SerialAnalyzer(); }

void DestroyAnalyzer(Analyzer *analyzer) { delete analyzer; }