mirror of
https://github.com/TomHarte/CLK.git
synced 2024-10-15 20:24:07 +00:00
66 lines
1.8 KiB
C++
66 lines
1.8 KiB
C++
|
//
|
||
|
// 65816Implementation.hpp
|
||
|
// Clock Signal
|
||
|
//
|
||
|
// Created by Thomas Harte on 23/09/2020.
|
||
|
// Copyright © 2020 Thomas Harte. All rights reserved.
|
||
|
//
|
||
|
|
||
|
#ifndef WDC65816Implementation_h
|
||
|
#define WDC65816Implementation_h
|
||
|
|
||
|
class ProcessorStorage {
|
||
|
public:
|
||
|
ProcessorStorage();
|
||
|
|
||
|
enum MicroOp: uint8_t {
|
||
|
/// Fetches a byte from the program counter to the instruction buffer and increments the program counter.
|
||
|
CycleFetchIncrementPC,
|
||
|
/// Fetches a byte from the data address to the data buffer and increments the data address.
|
||
|
CycleFetchIncrementData,
|
||
|
/// Stores a byte to the data address from the data buffer and increments the data address.
|
||
|
CycleStoreIncrementData,
|
||
|
|
||
|
/// Skips the next micro-op if in emulation mode.
|
||
|
OperationSkipIf8,
|
||
|
|
||
|
/// Sets the data address by copying the final two bytes of the instruction buffer.
|
||
|
OperationConstructAbsolute,
|
||
|
|
||
|
/// Performs whatever operation goes with this program.
|
||
|
OperationPerform,
|
||
|
|
||
|
/// Complete this set of micr-ops.
|
||
|
OperationMoveToNextProgram
|
||
|
};
|
||
|
|
||
|
enum Operation: uint8_t {
|
||
|
ADC, AND, BIT, CMP, CPX, CPY, EOR, LDA, LDX, LDY, ORA, SBC,
|
||
|
|
||
|
STA, STX, STY, STZ,
|
||
|
};
|
||
|
|
||
|
struct Instruction {
|
||
|
size_t program_offset;
|
||
|
Operation operation;
|
||
|
};
|
||
|
Instruction instructions[256];
|
||
|
|
||
|
private:
|
||
|
std::vector<MicroOp> micro_ops_;
|
||
|
|
||
|
size_t install_ops(std::initializer_list<MicroOp> ops) {
|
||
|
// Just copy into place and return the index at which copying began.
|
||
|
const size_t index = micro_ops_.size();
|
||
|
micro_ops_.insert(micro_ops_.end(), ops.begin(), ops.end());
|
||
|
return index;
|
||
|
}
|
||
|
|
||
|
void set_instruction(uint8_t opcode, size_t micro_ops, Operation operation) {
|
||
|
instructions[opcode].program_offset = micro_ops;
|
||
|
instructions[opcode].operation = operation;
|
||
|
}
|
||
|
};
|
||
|
|
||
|
#endif /* WDC65816Implementation_h */
|