6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-12-27 01:31:42 +00:00
Code Issues Projects Releases Wiki Activity

Attempted switching back to a square wave for the composite video and otherwise implementing what's necessary to get to that flashing cursor — the 6560 returns its scan line and the timing bits of the 6522 are appearing.

Browse Source
This commit is contained in:
Thomas Harte 2016-06-08 22:15:24 -04:00
parent 581eace478
commit e99055bedb
3 changed files with 68 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

60
Components/6522/6522.hpp
View File

@ -16,28 +16,74 @@ namespace MOS {
template <class T> class MOS6522 {
public:
MOS6522() : _data_direction{0, 0} {}
MOS6522() :
_data_direction{0, 0},
_timer_is_running{false, false}
{}
void set_register(int address, uint8_t value)
{
printf("6522: %d <- %02x\n", address, value);
// switch(address)
// {
// case 0x11: _auxiliary_control_register = value; break;
// }
address &= 0xf;
switch(address)
{
// Timer 1
case 0x06: case 0x04: _interval_timer_latch[0] = (_interval_timer_latch[0]&0xff00) | value; break;
case 0x05: case 0x07:
_interval_timer_latch[0] = (_interval_timer_latch[0]&0x00ff) | (uint16_t)(value << 8);
// TODO: clear interrupt flag
if(address == 0x05)
{
_interval_timer[0] = _interval_timer_latch[0];
_timer_is_running[0] = true;
}
break;
// Timer 2
case 0x08: _interval_timer_latch[1] = value; break;
case 0x09:
// TODO: clear interrupt flag
_interval_timer[1] = _interval_timer_latch[1] | (uint16_t)(value << 8);
_timer_is_running[1] = true;
break;
case 0x11: _auxiliary_control_register = value; break;
}
}
uint8_t get_register(int address)
{
printf("6522: %d\n", address);
address &= 0xf;
switch(address)
{
// Timer 1
case 0x04:
// TODO: clear interrupt flag
return _interval_timer[0] & 0x00ff;
case 0x05: return _interval_timer[0] >> 8;
case 0x06: return _interval_timer_latch[0] & 0x00ff;
case 0x07: return _interval_timer_latch[0] >> 8;
}
return 0xff;
}
void run_for_cycles(unsigned int number_of_cycles)
{
_interval_timer[0] -= number_of_cycles;
_interval_timer[1] -= number_of_cycles;
// TODO: interrupts, potentially reload of the first timer, other status effects
}
private:
uint16_t _interval_timers[2];
uint16_t _interval_timer[2], _interval_timer_latch[2];
uint8_t _shift_register;
uint8_t _input_latches[2];
uint8_t _input_latch[2];
uint8_t _data_direction[2];
bool _timer_is_running[2];
uint8_t _interrupt_flag_register, _interrupt_enable_register;
uint8_t _peripheral_control_register, _auxiliary_control_register;
};

12
Components/6560/6560.cpp
View File

@ -56,12 +56,14 @@ MOS6560::MOS6560() :
"uint iPhase = c & 7u;"
"float phaseOffset = 6.283185308 * float(iPhase + 8u) / 8.0;" // TODO: appropriate phaseOffset
"return mix(step(1, c) * y, step(2, c) * sin(phase + phaseOffset), amplitude);" // TODO: square wave (step(3.141592654, mod(phase + phaseOffset, 6.283185308))?)
// sin(phase + phaseOffset)
"return mix(step(1, c) * y, step(2, c) * step(3.141592654, mod(phase + phaseOffset, 6.283185308)) * 2.0, amplitude);" // TODO: square wave (step(3.141592654, mod(phase + phaseOffset, 6.283185308))?)
"}");
}
void MOS6560::set_register(int address, uint8_t value)
{
address &= 0xf;
_registers[address] = value;
switch(address)
{
@ -114,7 +116,13 @@ void MOS6560::set_register(int address, uint8_t value)
uint8_t MOS6560::get_register(int address)
{
return _registers[address];
address &= 0xf;
switch(address)
{
default: return _registers[address];
case 0x03: return ((_vertical_counter >> 1) & 0x80) | (_registers[3] & 0x7f);
case 0x04: return _vertical_counter & 0xff;
}
}

8
Machines/Vic-20/Vic20.cpp
View File

@ -12,7 +12,9 @@
using namespace Vic20;
Machine::Machine()
Machine::Machine() :
_userPortVIA(new UserPortVIA()),
_keyboardVIA(new KeyboardVIA())
{
set_reset_line(true);
}
@ -58,10 +60,10 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
{
_keyboardVIA->set_register(address - 0x9120, *value);
}
// TODO: the 6522
}
_userPortVIA->run_for_cycles(1);
_keyboardVIA->run_for_cycles(1);
return 1;
}