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Made an attempt to get video output correct.

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This commit is contained in:
Thomas Harte 2016-01-11 22:08:30 -05:00
parent e93dbdb463
commit 72019d0ea3
2 changed files with 123 additions and 21 deletions
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141
Machines/Electron/Electron.cpp
View File

@ -20,9 +20,11 @@ static const int crt_cycles_per_line = crt_cycles_multiplier * cycles_per_line;
Machine::Machine() : Machine::Machine() :
_interruptControl(0), _interruptControl(0),
_frameCycles(0), _frameCycles(0),
_outputPosition(0) _outputPosition(0),
_currentOutputLine(0)
{ {
memset(_keyStates, 0, sizeof(_keyStates)); memset(_keyStates, 0, sizeof(_keyStates));
memset(_palette, 0xf, sizeof(_palette));
_crt = new Outputs::CRT(crt_cycles_per_line, 312, 1, 1); _crt = new Outputs::CRT(crt_cycles_per_line, 312, 1, 1);
_interruptStatus = 0x02; _interruptStatus = 0x02;
setup6502(); setup6502();
@ -125,11 +127,56 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
printf("Counter\n"); printf("Counter\n");
break; break;
case 0x7: case 0x7:
printf("Misc. control\n"); if(!isReadOperation(operation))
{
_screenMode = ((*value) >> 3)&7;
if(_screenMode == 7) _screenMode = 4;
switch(_screenMode)
{
case 0: case 1: case 2: _screenModeBaseAddress = 0x3000; break;
case 3: _screenModeBaseAddress = 0x4000; break;
case 4: case 5: _screenModeBaseAddress = 0x5800; break;
case 6: _screenModeBaseAddress = 0x6000; break;
}
printf("Misc. control\n");
}
break; break;
default: default:
update_display(); {
// printf("Palette\n"); if(!isReadOperation(operation))
{
update_display();
static const int registers[4][4] = {
{10, 8, 2, 0},
{14, 12, 6, 4},
{15, 13, 7, 5},
{11, 9, 3, 1},
};
const int index = (address >> 1)&3;
const uint8_t colour = ~(*value);
if(address&1)
{
_palette[registers[index][0]] = (_palette[registers[index][0]]&3) | ((colour >> 1)&4);
_palette[registers[index][1]] = (_palette[registers[index][1]]&3) | ((colour >> 0)&4);
_palette[registers[index][2]] = (_palette[registers[index][2]]&3) | ((colour << 1)&4);
_palette[registers[index][3]] = (_palette[registers[index][3]]&3) | ((colour << 2)&4);
_palette[registers[index][2]] = (_palette[registers[index][2]]&5) | ((colour >> 4)&2);
_palette[registers[index][3]] = (_palette[registers[index][3]]&5) | ((colour >> 3)&2);
}
else
{
_palette[registers[index][0]] = (_palette[registers[index][0]]&6) | ((colour >> 7)&1);
_palette[registers[index][1]] = (_palette[registers[index][1]]&6) | ((colour >> 6)&1);
_palette[registers[index][2]] = (_palette[registers[index][2]]&6) | ((colour >> 5)&1);
_palette[registers[index][3]] = (_palette[registers[index][3]]&6) | ((colour >> 4)&1);
_palette[registers[index][0]] = (_palette[registers[index][0]]&5) | ((colour >> 2)&2);
_palette[registers[index][1]] = (_palette[registers[index][1]]&5) | ((colour >> 1)&2);
}
}
}
break; break;
} }
} }
@ -176,6 +223,7 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
update_display(); update_display();
_frameCycles = 0; _frameCycles = 0;
_outputPosition = 0; _outputPosition = 0;
_currentOutputLine = 0;
} }
if(_frameCycles == 128*128) signal_interrupt(InterruptRealTimeClock); if(_frameCycles == 128*128) signal_interrupt(InterruptRealTimeClock);
if(_frameCycles == 284*128) signal_interrupt(InterruptDisplayEnd); if(_frameCycles == 284*128) signal_interrupt(InterruptDisplayEnd);
@ -247,10 +295,12 @@ inline void Machine::update_display()
{ {
// on lines prior to 28 or after or equal to 284, or on a line that is equal to 8 or 9 modulo 10 in a line-spaced mode, // on lines prior to 28 or after or equal to 284, or on a line that is equal to 8 or 9 modulo 10 in a line-spaced mode,
// the line is then definitely blank. // the line is then definitely blank.
if( bool isBlankLine =
(current_line < 28 || current_line >= 284) ((_screenMode == 3) || (_screenMode == 6)) ?
// || (((current_line - 28)%10) > 7) ((current_line < 28 || current_line >= 277) || (((current_line - 28)%10) > 7)) :
) ((current_line < 28 || current_line >= 284));
if(isBlankLine)
{ {
if(line_position == 9) if(line_position == 9)
{ {
@ -276,19 +326,67 @@ inline void Machine::update_display()
if(line_position >= 24 && line_position < 104) if(line_position >= 24 && line_position < 104)
{ {
if(_currentLine) if(_currentLine && ((_screenMode < 4) || !(line_position&1)))
{ {
if(!(line_position&1)) if(_currentScreenAddress&32768)
{ {
uint8_t pixels = _ram[_currentScreenAddress]; _currentScreenAddress = _screenModeBaseAddress + (_currentScreenAddress&32767);
_currentScreenAddress += 8; }
int output_ptr = (line_position - 24) << 3; uint8_t pixels = _ram[_currentScreenAddress];
_currentScreenAddress = _currentScreenAddress+8;
int output_ptr = (line_position - 24) << 3;
for(int c = 0; c < 16; c+=2) switch(_screenMode)
{ {
_currentLine[output_ptr + c] = _currentLine[output_ptr + c + 1] = (pixels&0x80) ? 0 : 7; case 0:
pixels <<= 1; case 3:
} for(int c = 0; c < 8; c++)
{
uint8_t colour = (pixels&0x80) >> 4;
_currentLine[output_ptr + c] = _palette[colour];
pixels <<= 1;
}
break;
case 1:
for(int c = 0; c < 8; c += 2)
{
uint8_t colour = ((pixels&0x80) >> 4) | ((pixels&0x08) >> 2);
_currentLine[output_ptr + c + 0] = _currentLine[output_ptr + c + 1] = _palette[colour];
pixels <<= 1;
}
break;
case 2:
for(int c = 0; c < 8; c += 4)
{
uint8_t colour = ((pixels&0x80) >> 4) | ((pixels&0x20) >> 3) | ((pixels&0x08) >> 2) | ((pixels&0x02) >> 1);
_currentLine[output_ptr + c + 0] = _currentLine[output_ptr + c + 1] =
_currentLine[output_ptr + c + 2] = _currentLine[output_ptr + c + 3] = _palette[colour];
pixels <<= 1;
}
break;
case 5:
for(int c = 0; c < 16; c += 4)
{
uint8_t colour = ((pixels&0x80) >> 4) | ((pixels&0x08) >> 2);
_currentLine[output_ptr + c + 0] = _currentLine[output_ptr + c + 1] =
_currentLine[output_ptr + c + 2] = _currentLine[output_ptr + c + 3] = _palette[colour];
pixels <<= 1;
}
break;
default:
case 4:
case 6:
for(int c = 0; c < 16; c += 2)
{
uint8_t colour = (pixels&0x80) >> 4;
_currentLine[output_ptr + c] = _currentLine[output_ptr + c + 1] = _palette[colour];
pixels <<= 1;
}
break;
} }
} }
_outputPosition++; _outputPosition++;
@ -296,9 +394,10 @@ inline void Machine::update_display()
if(line_position == 104) if(line_position == 104)
{ {
if(!((current_line - 27)&7)) _currentOutputLine++;
if(!(_currentOutputLine&7))
{ {
_startLineAddress += 40*8 - 7; _startLineAddress += ((_screenMode < 4) ? 80 : 40)*8 - 7;
} }
else else
_startLineAddress++; _startLineAddress++;
@ -320,7 +419,7 @@ const char *Machine::get_signal_decoder()
"vec4 sample(vec2 coordinate)\n" "vec4 sample(vec2 coordinate)\n"
"{\n" "{\n"
"float texValue = texture(texID, srcCoordinatesVarying).r;\n" "float texValue = texture(texID, srcCoordinatesVarying).r;\n"
"return vec4( step(mod(texValue, 8.0/256.0), 4.0/256.0), step(mod(texValue, 4.0/256.0), 2.0/256.0), step(mod(texValue, 2.0/256.0), 1.0/256.0), 1.0);\n" "return vec4( step(4.0/256.0, mod(texValue, 8.0/256.0)), step(2.0/256.0, mod(texValue, 4.0/256.0)), step(1.0/256.0, mod(texValue, 2.0/256.0)), 1.0);\n"
"}"; "}";
} }

3
Machines/Electron/Electron.hpp
View File

@ -130,11 +130,14 @@ class Machine: public CPU6502::Processor<Machine> {
uint8_t _palette[16]; uint8_t _palette[16];
uint8_t _keyStates[14]; uint8_t _keyStates[14];
ROMSlot _activeRom; ROMSlot _activeRom;
uint8_t _screenMode;
uint16_t _screenModeBaseAddress;
Outputs::CRT *_crt; Outputs::CRT *_crt;
int _frameCycles, _outputPosition; int _frameCycles, _outputPosition;
uint16_t _startScreenAddress, _startLineAddress, _currentScreenAddress; uint16_t _startScreenAddress, _startLineAddress, _currentScreenAddress;
int _currentOutputLine;
uint8_t *_currentLine; uint8_t *_currentLine;
inline void update_display(); inline void update_display();