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There's finally a loop in here, at least.

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This commit is contained in:
Thomas Harte 2017-05-15 22:25:52 -04:00
parent df80c37adb
commit 50bb4f0142
2 changed files with 64 additions and 5 deletions
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6
Processors/MicroOpScheduler.hpp
View File

@ -41,6 +41,12 @@ template <class T> class MicroOpScheduler {
scheduled_programs_[schedule_programs_write_pointer_] = program;
schedule_programs_write_pointer_ = (schedule_programs_write_pointer_+1)&3;
}
inline void move_to_next_program() {
scheduled_programs_[schedule_programs_read_pointer_] = NULL;
schedule_programs_read_pointer_ = (schedule_programs_read_pointer_+1)&3;
schedule_program_program_counter_ = 0;
}
};
}

63
Processors/Z80/Z80.hpp
View File

@ -10,6 +10,7 @@
#define Z80_hpp
#include <cstdint>
#include <cstdio>
#include "../MicroOpScheduler.hpp"
#include "../RegisterSizes.hpp"
@ -61,19 +62,29 @@ enum Flag: uint8_t {
@c None is reserved for internal use. It will never be requested from a subclass.
*/
enum BusOperation {
ReadOpcode,
ReadOpcode = 0,
Read, Write,
Input, Output,
Interrupt,
BusRequest, BusAcknowledge,
// BusRequest, BusAcknowledge,
None
};
struct MachineCycle {
BusOperation operation;
const uint16_t *address;
uint8_t *value;
};
struct MicroOp {
enum {
BusOperation,
DecodeOperation,
MoveToNextProgram
} type;
void *source;
void *destination;
MachineCycle machine_cycle;
};
/*!
@ -95,19 +106,58 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
RegisterPair ix_, iy_, pc_, sp_;
uint8_t carry_flag_, sign_result_, bit5_result_, half_carry_flag_, bit3_result_, parity_overflow_flag_, subtract_flag_;
int number_of_cycles_;
uint8_t operation_;
constexpr static int cycles_by_bus_operation[6] = {
4,
3, 3,
3, 3,
3
};
public:
/*!
Runs the Z80 for a supplied number of cycles.
@discussion Subclasses must implement @c perform_bus_operation(BusOperation operation, uint16_t address, uint8_t *value) .
The Z80 will call that method for all bus accesses.
@discussion Subclasses must implement @c perform_machine_cycle(MachineCycle *cycle) .
If it is a read operation then @c value will be seeded with the value 0xff.
@param number_of_cycles The number of cycles to run the Z80 for.
*/
void run_for_cycles(int number_of_cycles) {
// TODO (!)
static const MicroOp fetch_decode_execute[] = {
{ MicroOp::BusOperation, nullptr, nullptr, {ReadOpcode, &pc_.full, &operation_}},
{ MicroOp::DecodeOperation },
{ MicroOp::MoveToNextProgram }
};
schedule_program(fetch_decode_execute);
MicroOp *operation = &scheduled_programs_[schedule_programs_read_pointer_][schedule_program_program_counter_];
number_of_cycles_ += number_of_cycles;
while(1) {
switch(operation->type) {
case MicroOp::BusOperation:
if(number_of_cycles_ < cycles_by_bus_operation[operation->type]) {
return;
}
perform_machine_cycle(&operation->machine_cycle);
break;
case MicroOp::MoveToNextProgram:
move_to_next_program();
operation--;
schedule_program_program_counter_--;
break;
default:
printf("Unhandled Z80 operation %d\n", operation->type);
return;
}
operation++;
schedule_program_program_counter_++;
}
}
/*!
@ -117,6 +167,9 @@ template <class T> class Processor: public MicroOpScheduler<MicroOp> {
*/
void flush() {}
void perform_machine_cycle(const MachineCycle *cycle) {
}
/*!
Gets the flags register.