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Implemented a catch for loading the data portion of files.

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This commit is contained in:
Thomas Harte 2017-05-07 22:22:59 -04:00
parent 2807e3134f
commit 7b43ae0a92
1 changed files with 24 additions and 26 deletions
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50
Machines/Commodore/Vic-20/Vic20.cpp
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@ -148,7 +148,30 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
*value = 0x0c; // i.e. NOP abs
} else if(address == 0xf90b) {
printf("Tape receive\n");
uint8_t x = (uint8_t)get_value_of_register(CPU6502::Register::X);
if(x == 0xe) {
Storage::Tape::Commodore::Parser parser;
std::unique_ptr<Storage::Tape::Commodore::Data> data = parser.get_next_data(tape_->get_tape());
uint16_t start_address, end_address;
start_address = (uint16_t)(user_basic_memory_[0xc1] | (user_basic_memory_[0xc2] << 8));
end_address = (uint16_t)(user_basic_memory_[0xae] | (user_basic_memory_[0xaf] << 8));
uint8_t *data_ptr = data->data.data();
while(start_address != end_address) {
processor_write_memory_map_[start_address >> 10][start_address & 0x3ff] = *data_ptr;
data_ptr++;
start_address++;
}
user_basic_memory_[0x90] |= 0x40;
uint8_t flags = (uint8_t)get_value_of_register(CPU6502::Register::Flags);
flags &= ~(uint8_t)(CPU6502::Flag::Carry | CPU6502::Flag::Interrupt);
set_value_of_register(CPU6502::Register::Flags, flags);
set_value_of_register(CPU6502::Register::ProgramCounter, 0xfccf + 1);
*value = 0x08;
}
}
}
} else {
@ -172,31 +195,6 @@ unsigned int Machine::perform_bus_operation(CPU6502::BusOperation operation, uin
tape_->run_for_cycles(1);
if(c1540_) c1540_->run_for_cycles(1);
// If using fast tape then:
// if the PC hits 0xf98e, the ROM's tape loading routine, then begin zero cost processing;
// if the PC heads into RAM
//
// Where 'zero cost processing' is taken to be taking the 6560 off the bus (because I know it's
// expensive, and not relevant) then running the tape, the CPU and both 6522s as usual but not
// counting cycles towards the processing budget. So the limit is the host machine.
//
// Note the additional test above for PC hitting 0xf92f, which is a loop in the ROM that waits
// for an interesting interrupt. Up there the fast tape hack goes even further in also cutting
// the CPU out of the action.
/* if(use_fast_tape_hack_ && tape_->has_tape()) {
if(address == 0xf98e && operation == CPU6502::BusOperation::ReadOpcode) {
is_running_at_zero_cost_ = true;
set_clock_is_unlimited(true);
}
if(
(address < 0xe000 && operation == CPU6502::BusOperation::ReadOpcode) ||
tape_->get_tape()->is_at_end()
) {
is_running_at_zero_cost_ = false;
set_clock_is_unlimited(false);
}
}*/
return 1;
}