6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-12-23 20:29:42 +00:00
Code Issues Projects Releases Wiki Activity

Made attempt to run at zero cost while processing tape input.

Browse Source
This commit is contained in:
Thomas Harte 2016-09-11 17:34:02 -04:00
parent eeec516fa6
commit e54a2326a3
2 changed files with 12 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
Machines/Commodore/Vic-20/Vic20.cpp
View File

@ -15,7 +15,8 @@
using namespace Commodore::Vic20;
Machine::Machine() :
_rom(nullptr)
_rom(nullptr),
_is_running_at_zero_cost(false)
{
// create 6522s, serial port and bus
_userPortVIA.reset(new UserPortVIA);
@ -115,7 +116,7 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
// }
// run the phase-1 part of this cycle, in which the VIC accesses memory
_mos6560->run_for_cycles(1);
if(!_is_running_at_zero_cost) _mos6560->run_for_cycles(1);
// run the phase-2 part of the cycle, which is whatever the 6502 said it should be
if(isReadOperation(operation))
@ -165,7 +166,14 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
}
_tape.run_for_cycles(1);
if(_c1540) _c1540->run_for_cycles(1);
return 1;
if(_use_fast_tape_hack && operation == CPU6502::BusOperation::ReadOpcode)
{
if(address == 0xF98E) _is_running_at_zero_cost = true;
if(address == 0xff56) _is_running_at_zero_cost = false;
}
return _is_running_at_zero_cost ? 0 : 1;
}
#pragma mark - 6522 delegate

1
Machines/Commodore/Vic-20/Vic20.hpp
View File

@ -334,6 +334,7 @@ class Machine:
// Tape
Tape _tape;
bool _use_fast_tape_hack, _should_automatically_load_media;
bool _is_running_at_zero_cost;
// Disk
std::shared_ptr<::Commodore::C1540::Machine> _c1540;