6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-12-25 03:32:01 +00:00
Code Issues Projects Releases Wiki Activity

Some minor optimisations and timing tweaks. Nothing of substance.

Browse Source
This commit is contained in:
Thomas Harte 2016-03-10 19:58:50 -05:00
parent df3fff51c7
commit 20ac630e4d
2 changed files with 28 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
Machines/Electron/Electron.cpp
View File

@ -101,7 +101,7 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
if(isReadOperation(operation)) if(isReadOperation(operation))
{ {
*value = _interrupt_status; *value = _interrupt_status;
_interrupt_status &= ~0x02; _interrupt_status &= ~PowerOnReset;
} }
else else
{ {
@ -283,8 +283,8 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
// } // }
unsigned int start_of_graphics = get_first_graphics_cycle(); unsigned int start_of_graphics = get_first_graphics_cycle();
const unsigned int real_time_clock_interrupt_time = start_of_graphics + 99*128; const unsigned int real_time_clock_interrupt_time = start_of_graphics + 128*128;
const unsigned int display_end_interrupt_time = start_of_graphics + 257*128 + 64; const unsigned int display_end_interrupt_time = start_of_graphics + 264*128;
if(_fieldCycles < real_time_clock_interrupt_time && _fieldCycles + cycles >= real_time_clock_interrupt_time) if(_fieldCycles < real_time_clock_interrupt_time && _fieldCycles + cycles >= real_time_clock_interrupt_time)
{ {

38
Processors/6502/CPU6502.hpp
View File

@ -545,9 +545,15 @@ template <class T> class Processor {
OperationMoveToNextProgram OperationMoveToNextProgram
}; };
// These plus program below act to give the compiler permission to update these values
// without touching the class storage (i.e. it explicitly says they need be completely up
// to date in this stack frame only); which saves some complicated addressing
unsigned int scheduleProgramsReadPointer = _scheduleProgramsReadPointer;
unsigned int scheduleProgramProgramCounter = _scheduleProgramProgramCounter;
#define checkSchedule(op) \ #define checkSchedule(op) \
if(!_scheduledPrograms[_scheduleProgramsReadPointer]) {\ if(!_scheduledPrograms[scheduleProgramsReadPointer]) {\
_scheduleProgramsReadPointer = _scheduleProgramsWritePointer = _scheduleProgramProgramCounter = 0;\ scheduleProgramsReadPointer = _scheduleProgramsWritePointer = scheduleProgramProgramCounter = 0;\
if(_reset_line_is_enabled)\ if(_reset_line_is_enabled)\
schedule_program(get_reset_program());\ schedule_program(get_reset_program());\
else\ else\
@ -561,25 +567,26 @@ template <class T> class Processor {
} }
checkSchedule(); checkSchedule();
_cycles_left_to_run += number_of_cycles; number_of_cycles += _cycles_left_to_run;
const MicroOp *program = _scheduledPrograms[scheduleProgramsReadPointer];
while(_cycles_left_to_run > 0) { while(number_of_cycles > 0) {
while (_ready_is_active && _cycles_left_to_run > 0) { while (_ready_is_active && number_of_cycles > 0) {
_cycles_left_to_run -= static_cast<T *>(this)->perform_bus_operation(BusOperation::Ready, _busAddress, _busValue); number_of_cycles -= static_cast<T *>(this)->perform_bus_operation(BusOperation::Ready, _busAddress, _busValue);
} }
while (!_ready_is_active && _cycles_left_to_run > 0) { while (!_ready_is_active && number_of_cycles > 0) {
if (_nextBusOperation != BusOperation::None) { if (_nextBusOperation != BusOperation::None) {
_irq_request_history[0] = _irq_request_history[1]; _irq_request_history[0] = _irq_request_history[1];
_irq_request_history[1] = _irq_line_is_enabled && !_interruptFlag; _irq_request_history[1] = _irq_line_is_enabled && !_interruptFlag;
_cycles_left_to_run -= static_cast<T *>(this)->perform_bus_operation(_nextBusOperation, _busAddress, _busValue); number_of_cycles -= static_cast<T *>(this)->perform_bus_operation(_nextBusOperation, _busAddress, _busValue);
_nextBusOperation = BusOperation::None; _nextBusOperation = BusOperation::None;
} }
const MicroOp cycle = _scheduledPrograms[_scheduleProgramsReadPointer][_scheduleProgramProgramCounter]; const MicroOp cycle = program[scheduleProgramProgramCounter];
_scheduleProgramProgramCounter++; scheduleProgramProgramCounter++;
#define read_op(val, addr) _nextBusOperation = BusOperation::ReadOpcode; _busAddress = addr; _busValue = &val #define read_op(val, addr) _nextBusOperation = BusOperation::ReadOpcode; _busAddress = addr; _busValue = &val
#define read_mem(val, addr) _nextBusOperation = BusOperation::Read; _busAddress = addr; _busValue = &val #define read_mem(val, addr) _nextBusOperation = BusOperation::Read; _busAddress = addr; _busValue = &val
@ -616,10 +623,11 @@ template <class T> class Processor {
break; break;
case OperationMoveToNextProgram: case OperationMoveToNextProgram:
_scheduledPrograms[_scheduleProgramsReadPointer] = NULL; _scheduledPrograms[scheduleProgramsReadPointer] = NULL;
_scheduleProgramsReadPointer = (_scheduleProgramsReadPointer+1)&3; scheduleProgramsReadPointer = (scheduleProgramsReadPointer+1)&3;
_scheduleProgramProgramCounter = 0; scheduleProgramProgramCounter = 0;
checkSchedule(); checkSchedule();
program = _scheduledPrograms[scheduleProgramsReadPointer];
break; break;
#define push(v) \ #define push(v) \
@ -1035,6 +1043,10 @@ template <class T> class Processor {
_ready_is_active = true; _ready_is_active = true;
} }
} }
_cycles_left_to_run = number_of_cycles;
_scheduleProgramsReadPointer = scheduleProgramsReadPointer;
_scheduleProgramProgramCounter = scheduleProgramProgramCounter;
} }
} }