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//#include "stdafx.h"
#include "TZXBlockStandardSpeedData.h"
#include "TZXFile.h"
#include <stdlib.h>
#include <stdio.h>
TZXBlockStandardSpeedData::TZXBlockStandardSpeedData()
{
m_nBlockID = TZX_BLOCKID_STANDARD_SPEED_DATA;
m_pData = NULL;
m_nLengthOfData = 0;
m_nPauseAfterBlockInMS = 0;
}
TZXBlockStandardSpeedData::~TZXBlockStandardSpeedData()
{
if (m_pData) free(m_pData);
}
char *TZXBlockStandardSpeedData::GetDescription()
{
snprintf((char *)m_szToStringDescription, MAX_STRING_LENGTH, "Standard Speed Data Block: %d bytes. Delay = %d ms", m_nLengthOfData, m_nPauseAfterBlockInMS);
return m_szToStringDescription;
}
void TZXBlockStandardSpeedData::GenerateAudio(TZXAudioGenerator *pAudioGenerator, TZXFile *pTZXFile)
{
// Store the offset location for the current block
m_nAudioBufferOffsetLocation = pAudioGenerator->GetCurrentLength();
// What type of stadard block are we, header or data?
// Get the flag byte...
int dataType = m_pData[0];
if (dataType == 0)
{
// It's a header block...
// Generate the standard header pilot pulse
pAudioGenerator->SetAmp(false); // Make sure the pilot always starts on a false.
for (int i = 0; i <= TZX_PILOT_PULSES_HEADER; i++)
{
pAudioGenerator->GeneratePulse(TZX_PILOT_PULSE_LENGTH);
}
}
else {
// It's a data block
// Generate the standard data pilot pulse
pAudioGenerator->SetAmp(false); // Make sure the pilot always starts on a false.
for (int i = 0; i <= TZX_PILOT_PULSES_DATA; i++)
{
pAudioGenerator->GeneratePulse(TZX_PILOT_PULSE_LENGTH);
}
}
// Generate the two sync pulses
pAudioGenerator->GeneratePulse(TZX_FIRST_SYNC_PULSE_LENGTH);
pAudioGenerator->GeneratePulse(TZX_SECOND_SYNC_PULSE_LENGTH);
// Generate the actual data
for (int i = 0; i < m_nLengthOfData; i++)
{
for (int n = 7; n >= 0; n--)
{
char mask = 1 << n;
char bitset = m_pData[i] & mask;
if (bitset)
{
// Write a one bit
pAudioGenerator->GeneratePulse(TZX_ONE_BIT_LENGTH);
pAudioGenerator->GeneratePulse(TZX_ONE_BIT_LENGTH);
}
else {
// Write a zero bit
pAudioGenerator->GeneratePulse(TZX_ZERO_BIT_LENGTH);
pAudioGenerator->GeneratePulse(TZX_ZERO_BIT_LENGTH);
}
}
}
// Add any delay at the end of the block
if (m_nPauseAfterBlockInMS) pAudioGenerator->AddSilence(m_nPauseAfterBlockInMS);
}
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