/
fc_cpu.py
executable file
·1029 lines (904 loc) · 29.1 KB
/
fc_cpu.py
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from typing import List
import json
from utils import (
log,
bytes_to_int,
sign,
FlagByte,
)
from config import (
order_size,
order_code,
)
import copy
import fc_ppu
import fc_gamepad
import os
def log_to_json():
f = open('nestest初始化完成.log')
r = []
for line in f:
words = line.split()
PC = int(words[1], base=16)
op = words[2]
address = int(words[4], base=16)
A = int(words[5].split(':')[1], base=16)
X = int(words[6].split(':')[1], base=16)
Y = int(words[7].split(':')[1], base=16)
S = int(words[8].split(':')[1], base=16)
P = int(words[9].split(':')[1] + words[10], base=2)
d = {
'PC': PC,
'op': op,
'address': address,
'A': A,
'X': X,
'Y': Y,
'S': S,
'P': P,
}
r.append(d)
s = json.dumps(r)
f.close()
with open('nestest初始化完成.json', 'w') as f:
f.write(s)
class Checker:
def __init__(self, mode='ppu'):
if mode == 'cpu':
log_path = 'nestest_log.json'
elif mode == 'ppu':
log_path = 'nestest初始化完成.json'
log('Checker mode:', mode)
with open(log_path) as f:
j = f.read()
self.logs = json.loads(j)
self.line = 0
def check(self, cpu_info: dict):
record = self.logs[self.line]
# if info:
# print('now line========>', self.line)
# print(cpu_info)
# print(record)
assert record == cpu_info, (record, cpu_info)
self.next_line()
def next_line(self):
self.line += 1
class Cpu:
def __init__(self):
self.space = CpuSpace()
self.ppu = self.space.ppu
p = FlagByte(0b00100100)
self.registers = {
'A': 0,
'X': 0,
'Y': 0,
'PC': 0,
'S': 0xFD,
'P': p,
}
self.orders = order_code()
self.sizes = order_size()
self.IRQ_AD = 0xFFFE
self.NMI_AD = 0xFFFA
self._cur_value = None
self.info = False
self.checker = Checker(mode='cpu')
# 快速存档
def dumps(self):
c_registers = copy.copy(self.registers)
for key, value in c_registers.items():
if isinstance(value, FlagByte):
c_registers[key] = value.flag
d = {
'registers': c_registers,
}
c_registers = copy.copy(self.registers)
for key, value in c_registers.items():
if isinstance(value, FlagByte):
c_registers[key] = value.flag
d = {
'registers': c_registers,
}
allow_attr = []
for attr_name in allow_attr:
d[attr_name] = getattr(self, attr_name)
j = json.dumps(d)
with open('save/cpu_save.json', 'w') as f:
f.write(j)
self.space.dumps()
# 快速读档
def loads(self):
with open('save/cpu_save.json') as f:
data = f.read()
d = json.loads(data)
for name, value in d.items():
setattr(self, name, value)
registers = d['registers']
for name in registers.keys():
if name in ['P']:
value = FlagByte(registers[name])
else:
value = registers[name]
self.registers[name] = value
self.space.loads()
def run(self):
log('=====loop_5000====')
self.loop_5000()
def loop_logs(self):
self.registers['PC'] = 0xC000
for i in range(len(self.checker.logs)):
self.debug_run_order()
def loop_5000(self):
for i in range(5000):
self.run_order()
def loop_10000(self):
for i in range(10000):
self.run_order()
def loop_20000(self):
for i in range(20000):
self.run_order()
def debug_run_order(self):
self._cur_value = None
self.parse_order()
self.eval_ad()
cpu_info = {
'PC': self.PC,
'op': self.cur_order,
'address': self.cur_ad,
'A': self.A,
'X': self.X,
'Y': self.Y,
'P': self.registers['P'].flag,
'S': self.S,
}
self.checker.check(cpu_info)
# log('[info]PC', ff(self.PC), self.cur_order, self.ad_type, ff(self.cur_ad), 'A:', ff(self.A), 'X:', ff(self.X), 'Y:', ff(self.Y), 'S:', ff(self.S))
self.add_pc()
self.execute()
def run_order(self):
self._cur_value = None
self.parse_order()
self.eval_ad()
if self.info:
log('cur_order', self.cur_order)
log('ad_type', self.ad_type)
size = self.sizes[self.ad_type]
log('ad_args', self.space[self.PC + 1: self.PC + size])
log('cur_ad', self.cur_ad)
self.add_pc()
self.execute()
def load_prg_rom(self, data_prgrom: bytes):
# 暂时实现16kb
self.space[0x8000:0xC000] = data_prgrom[:16384]
self.space[0xC000:] = data_prgrom[-16384:]
# 加载PC
start_index = bytes_to_int(self.space[0xFFFC:0xFFFC + 2])
self.PC = start_index
self.space[0x2002] = 0b10100000
def load_chr_rom(self, data_chrrom: bytes):
self.space.ppu.space[0x0000:0x1FFF] = data_chrrom
@property
def cur_value(self):
if self._cur_value is None:
self._cur_value = self.space[self.cur_ad]
value = self._cur_value
return value
@property
def PC(self):
return self.registers['PC']
@PC.setter
def PC(self, value: int):
self.registers['PC'] = value % 65536
@property
def X(self):
return self.registers['X']
@X.setter
def X(self, value: int):
self.registers['X'] = value % 256
@property
def Y(self):
return self.registers['Y']
@Y.setter
def Y(self, value: int):
self.registers['Y'] = value % 256
@property
def A(self):
return self.registers['A']
@A.setter
def A(self, value: int):
self.registers['A'] = value % 256
@property
def S(self):
return self.registers['S']
@S.setter
def S(self, value: int):
self.registers['S'] = value % 256
def add_pc(self):
order = self.space[self.PC]
_, ad_type = self.orders[order]
size = self.sizes[ad_type]
self.PC += size
def parse_order(self):
order = self.space[self.PC]
order_name, ad_type = self.orders[order]
self.ad_type = ad_type
self.cur_order = order_name
def eval_ad(self):
ad_type = self.ad_type
size = self.sizes[ad_type]
ad_args = self.space[self.PC + 1: self.PC + size]
if ad_type == 'ABS':
# 绝对地址
cur_ad = bytes_to_int(ad_args)
elif ad_type == 'IMM':
# 直接赋值 cur_ad供log用
cur_ad = bytes_to_int(ad_args)
self._cur_value = cur_ad
elif ad_type == 'ZPG':
# 零页地址
cur_ad = bytes_to_int(ad_args)
elif ad_type == 'IMP':
# 内部定义,不需要外部值
cur_ad = -1
elif ad_type == 'REL':
# 间接地址 需要正负号 考虑地址溢出
offset = bytes_to_int(ad_args, signed=True)
size = self.sizes[self.ad_type]
ad = self.PC + size + offset & 0xffff
cur_ad = ad
# value = self.space[cur_ad]
elif ad_type == 'ABX':
# 考虑地址溢出
y = self.X
base_ad = bytes_to_int(ad_args)
cur_ad = (base_ad + y) & 0xffff
# value = self.space[cur_ad]
elif ad_type == 'ABY':
# 考虑 地址溢出
y = self.Y
base_ad = bytes_to_int(ad_args)
cur_ad = (base_ad + y) % 65536
# value = self.space[cur_ad]
elif ad_type == 'ZPX':
# 考虑零页溢出
offset = bytes_to_int(ad_args)
cur_ad = (self.X + offset) % 256
# value = self.space[cur_ad]
elif ad_type == 'ZPY':
# 考虑零页溢出
offset = bytes_to_int(ad_args)
cur_ad = (self.Y + offset) % 256
elif ad_type == 'INX':
# 间接系列,存在bug. order ($xxFF)无法正常工作.
base_ad = (ad_args[0] + self.X) & 0xff
low = (base_ad) & 0xff
high = (base_ad + 1) & 0xff
real_ad = [self.space[low], self.space[high]]
cur_ad = bytes_to_int(real_ad)
elif ad_type == 'INY':
# 间接系列,存在bug. order ($xxFF)无法正常工作.
base_ad = ad_args[0]
if base_ad % 256 == 255:
real_ad = [self.space[base_ad], self.space[base_ad - 255]]
else:
real_ad = self.space[base_ad: base_ad + 2]
cur_ad = (bytes_to_int(real_ad) + self.Y) % 65536
# value = self.space[cur_ad]
elif ad_type == 'IND':
# 间接系列,存在bug. order ($xxFF)无法正常工作.
base_ad = bytes_to_int(ad_args)
if base_ad % 256 == 255:
real_ad = [self.space[base_ad], self.space[base_ad - 255]]
else:
real_ad = self.space[base_ad: base_ad + 2]
cur_ad = bytes_to_int(real_ad)
else:
print('未实现的寻址', ad_type)
raise Exception('未实现的寻址', ad_type)
self.cur_ad = cur_ad
def execute(self):
order_func = getattr(self, self.cur_order)
order_func()
def JMP(self):
self.PC = self.cur_ad
def LDX(self):
self.X = self.cur_value
self.check_z_flag(self.X)
self.check_n_flag(self.X)
def LDA(self):
self.A = self.cur_value
self.check_z_flag(self.A)
self.check_n_flag(self.A)
def STX(self):
self.space[self.cur_ad] = self.X
def STA(self):
# if (self.X) == 0x20:
# log('right stx', self.X, self.cur_ad)
self.space[self.cur_ad] = self.A
def STY(self):
self.space[self.cur_ad] = self.Y
def JSR(self):
value = self.PC - 1
self.stack_push(value, size=2)
self.PC = self.cur_ad
def NOP(self):
pass
def SEC(self):
self.registers['P'][0] = 1
def SEC(self):
self.registers['P'][0] = 1
def BCS(self):
carry_flag = self.registers['P'][6]
if carry_flag:
self.PC = self.cur_value
def BCS(self):
# Branch if Carry Set
carry_flag = self.registers['P'][0]
if carry_flag is 1:
self.PC = self.cur_ad
def BCC(self):
# Branch if Carry clear
carry_flag = self.registers['P'][0]
if carry_flag is 0:
self.PC = self.cur_ad
def CLC(self):
self.registers['P'][0] = 0
def BEQ(self):
# Branch if Zero Set
zero_flag = self.registers['P'][1]
if zero_flag is 1:
self.PC = self.cur_ad
def BNE(self):
# Branch if Zero Clear
zero_flag = self.registers['P'][1]
if zero_flag == 0:
self.PC = self.cur_ad
def BIT(self):
value = self.cur_value
a = self.A
r = a & value
self.check_z_flag(r)
m_flag = FlagByte(value)
self.registers['P'][7] = m_flag[7]
self.registers['P'][6] = m_flag[6]
def BVS(self):
# Branch if V Set
v_flag = self.registers['P'][6]
if v_flag is 1:
self.PC = self.cur_ad
def BVC(self):
# Branch if V clear
v_flag = self.registers['P'][6]
if v_flag is 0:
self.PC = self.cur_ad
def BPL(self):
# Branch if V n_flag is clear
n_flag = self.registers['P'][7]
if n_flag is 0:
self.PC = self.cur_ad
def RTS(self):
# 直接存+1后地址不好么
value = self.stack_pop(size=2)
self.PC = value + 1
def SEI(self):
# 设置P中的Interrupt Disable为1
self.registers['P'][2] = 1
def SED(self):
# 设置P中的Set Decimal Flag为1
self.registers['P'][3] = 1
def PHP(self):
# 复制一份P,并依据指令修改后推入stack
p = copy.copy(self.registers['P'])
p[4] = 1
p[5] = 1
self.stack_push(p.flag)
def PLA(self):
# 从stack pull 1字节
value = self.stack_pop()
self.check_z_flag(value)
self.check_n_flag(value)
self.A = value
def AND(self):
# 'And' memory with A
r = self.A & self.cur_value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def CMP(self):
# 'And' memory with A, then A = memory_value
r = self.A - self.cur_value
if r >= 0:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
self.check_z_flag(r)
self.check_n_flag(r)
def CLD(self):
# 清除P中的d flag
self.registers['P'][3] = 0
def PHA(self):
# 从A装的值 push stack
value = self.A
self.stack_push(value)
def PLP(self):
# 从stack pop 8位 装载至p
# warnning 4/5位保持原样
value = self.stack_pop()
new_p = FlagByte(value)
old_p = self.registers['P']
new_p[4] = old_p[4]
new_p[5] = old_p[5]
self.registers['P'] = new_p
def BMI(self):
# 如果n_flag为1,跳转
n_flag = self.registers['P'][7]
if n_flag == 1:
self.PC = self.cur_ad
def ORA(self):
# 'Or' memory with A
r = self.A | self.cur_value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def CLV(self):
# 清除P中的V_flag
self.registers['P'][6] = 0
def EOR(self):
r = self.A ^ self.cur_value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def ADC(self):
"""
emm 看婉仪的吧
"""
# r = A + M + c_flay
result = self.A + self.cur_value + self.registers['P'][0]
signed_a = sign(self.A)
signed_value = sign(self.cur_value)
signed_result = signed_a + signed_value + self.registers['P'][0]
if result > 255:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
if signed_result < -127 or signed_result > 128:
self.registers['P'][6] = 1
else:
self.registers['P'][6] = 0
set_value = result % 256
self.check_z_flag(set_value)
self.check_n_flag(set_value)
self.A = set_value
def LDY(self):
# set Y from memory
value = self.cur_value
self.check_z_flag(value)
self.check_n_flag(value)
self.Y = value
def LDX(self):
# set Y from memory
value = self.cur_value
self.check_z_flag(value)
self.check_n_flag(value)
self.X = value
def CPY(self):
r = self.Y - self.cur_value
if r >= 0:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
self.check_z_flag(r)
self.check_n_flag(r)
def CPX(self):
r = self.X - self.cur_value
if r >= 0:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
self.check_z_flag(r)
self.check_n_flag(r)
def SBC(self):
# A = A - M - (1-C)
# 从累加器减去存储器和进位标志C,结果送累加器A.
result = self.A - self.cur_value - (1 - self.registers['P'][0])
signed_a = sign(self.A)
signed_value = sign(self.cur_value)
signed_result = signed_a - signed_value - (1 - self.registers['P'][0])
# signed_result = signed_a - signed_value - self.registers['P'][0]
if result < 0 or result > 255:
self.registers['P'][0] = 0
else:
self.registers['P'][0] = 1
if signed_result < -127 or signed_result > 128:
self.registers['P'][6] = 1
else:
self.registers['P'][6] = 0
set_value = result % 256
self.check_z_flag(set_value)
self.check_n_flag(set_value)
self.A = set_value
def INY(self):
self.Y += 1
self.check_z_flag(self.Y)
self.check_n_flag(self.Y)
def INX(self):
self.X += 1
self.check_z_flag(self.X)
self.check_n_flag(self.X)
def INC(self):
# Increment Memory
# 头疼的溢出问题
value = (self.space[self.cur_ad] + 1) % 256
self.check_z_flag(value)
self.check_n_flag(value)
self.space[self.cur_ad] = value
def DEY(self):
self.Y -= 1
self.check_z_flag(self.Y)
self.check_n_flag(self.Y)
def DEX(self):
self.X -= 1
self.check_z_flag(self.X)
self.check_n_flag(self.X)
def DEC(self):
# Increment Memory
# 头疼的溢出问题
value = (self.space[self.cur_ad] - 1) % 256
self.check_z_flag(value)
self.check_n_flag(value)
self.space[self.cur_ad] = value
def TAY(self):
self.Y = self.A
self.check_z_flag(self.Y)
self.check_n_flag(self.Y)
def TAX(self):
self.X = self.A
self.check_z_flag(self.X)
self.check_n_flag(self.X)
def TYA(self):
self.A = self.Y
self.check_z_flag(self.A)
self.check_n_flag(self.A)
def TXA(self):
self.A = self.X
self.check_z_flag(self.A)
self.check_n_flag(self.A)
def TSX(self):
self.X = self.S
self.check_z_flag(self.X)
self.check_n_flag(self.X)
def TXS(self):
# 不影响p
self.S = self.X
def RTI(self):
# 从栈中先提取8位p, z
p = self.stack_pop()
new_p = FlagByte(p)
old_p = self.registers['P']
new_p[4] = old_p[4]
new_p[5] = old_p[5]
self.registers['P'] = new_p
pc = self.stack_pop(size=2)
self.PC = pc
def LSR(self):
# A 或内存的值,右移一位。原bit_0 放置到c_flag
if self.ad_type == "IMP":
bit_0 = self.A & 1
value = self.A >> 1
self.A = value
else:
bit_0 = self.cur_value & 1
value = self.cur_value >> 1
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_0
self.check_z_flag(value)
self.check_n_flag(value)
def ASL(self):
# A 或内存的值,左移一位。原bit_7 放置到c_flag
if self.ad_type == "IMP":
bit_7 = (self.A >> 7) & 1
value = (self.A << 1) % 256
self.A = value
else:
bit_7 = (self.cur_value >> 7) & 1
value = (self.cur_value << 1) % 256
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_7
self.check_z_flag(value)
self.check_n_flag(value)
def ROR(self):
# 右移动1位, 原C位站bit_7,原bit_0站c位
c = self.registers['P'][0]
if self.ad_type == "IMP":
bit_0 = self.A & 1
value = (self.A >> 1) % 128 + (c << 7)
self.A = value
else:
bit_0 = self.cur_value & 1
value = (self.cur_value >> 1) % 128 + (c << 7)
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_0
self.check_z_flag(value)
self.check_n_flag(value)
def ROL(self):
# 左移动1位, c_flag站bit_0, 原bit_7去c_flag
c = self.registers['P'][0]
if self.ad_type == "IMP":
bit_7 = (self.A >> 7) & 1
value = (self.A << 1) % 256 + c
self.A = value
else:
bit_7 = (self.cur_value >> 7) & 1
value = (self.cur_value << 1) % 256 + c
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_7
self.check_z_flag(value)
self.check_n_flag(value)
def LAX(self):
self.A = self.cur_value
self.X = self.A
self.check_z_flag(self.A)
self.check_n_flag(self.A)
def SAX(self):
self.space[self.cur_ad] = self.A & self.X
def DCP(self):
# Decrement memory then Compare with A
# DEC + CMP
self.space[self.cur_ad] = (self.space[self.cur_ad] - 1) % 256
c = self.A - self.space[self.cur_ad]
if c >= 0:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
self.check_z_flag(c)
self.check_n_flag(c)
def ISB(self):
# Increment memory then Subtract with Carry
# INC + SBC
self.space[self.cur_ad] = (self.space[self.cur_ad] + 1) % 256
result = self.A - self.space[self.cur_ad] - (1 - self.registers['P'][0])
signed_a = sign(self.A)
signed_value = sign(self.space[self.cur_ad])
signed_result = signed_a - signed_value - (1 - self.registers['P'][0])
if result < 0 or result > 255:
self.registers['P'][0] = 0
else:
self.registers['P'][0] = 1
if signed_result < -127 or signed_result > 128:
self.registers['P'][6] = 1
else:
self.registers['P'][6] = 0
set_value = result % 256
self.check_z_flag(set_value)
self.check_n_flag(set_value)
self.A = set_value
def SLO(self):
# Shift Left then 'Or' -
# ASL + ORA
# 由于要和累加器计算, 所以没有单字节指令SLO A, 没有IMP
bit_7 = (self.cur_value >> 7) & 1
value = (self.cur_value << 1) % 256
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_7
r = self.A | value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def RLA(self):
# Rotate Left then 'And'
# ROL + AND
# 同样用到了A, 也没有IMP的情况
c = self.registers['P'][0]
bit_7 = (self.cur_value >> 7) & 1
value = (self.cur_value << 1) % 256 + c
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_7
r = self.A & value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def SRE(self):
# Shift Right then "Exclusive-Or"
# LSR + EOR
# 同样用到了A, 也没有IMP的情况
bit_0 = self.cur_value & 1
value = self.cur_value >> 1
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_0
r = self.A ^ value
self.check_z_flag(r)
self.check_n_flag(r)
self.A = r
def RRA(self):
# Rotate Right then Add with Carry
# ROR + ADC
# 同样用到了A, 也没有IMP的情况
c = self.registers['P'][0]
bit_0 = self.cur_value & 1
value = (self.cur_value >> 1) % 128 + (c << 7)
self.space[self.cur_ad] = value
self.registers['P'][0] = bit_0
result = self.A + value + self.registers['P'][0]
signed_a = sign(self.A)
signed_value = sign(value)
signed_result = signed_a + signed_value + self.registers['P'][0]
if result > 255:
self.registers['P'][0] = 1
else:
self.registers['P'][0] = 0
if signed_result < -127 or signed_result > 128:
self.registers['P'][6] = 1
else:
self.registers['P'][6] = 0
set_value = result % 256
self.check_z_flag(set_value)
self.check_n_flag(set_value)
self.A = set_value
def NMI(self):
# 即要等到这次 NMI 执行结束之后,才能引起下一次 NMI
# self.space[0x2000][7] = 0
# 这个不是汇编指令,但暂时也放在这里。
self.stack_push(self.PC, size=2)
P = copy.copy(self.registers['P'])
P[4] = 0
p = P.flag
self.stack_push(p)
pc_bytes = self.space[self.NMI_AD: self.NMI_AD + 2]
pc = bytes_to_int(pc_bytes)
self.PC = pc
# def BRK(self):
# # 没有log测试
# # 强行PC + 1 指令要求
# self.PC += 1
# pc_h = self.PC // 256
# pc_l = self.PC % 256
# p = self.registers['P'].flag
# self.stack_push(pc_h)
# self.stack_push(pc_l)
# self.stack_push(p)
# low = self.space[self.IRQ_AD]
# high = self.space[self.IRQ_AD+1]
# self.PC = high * 256 + low
def check_z_flag(self, value):
if value == 0:
self.registers['P'][1] = 1
else:
self.registers['P'][1] = 0
def check_n_flag(self, value):
a7 = FlagByte(value)[7]
if a7 == 1:
self.registers['P'][7] = 1
else:
self.registers['P'][7] = 0
def stack_push(self, value, size=1):
# S其实是个偏移量,栈空间存从第一页开始
s = self.S + 256
if size == 1:
self.space[s] = value
elif size == 2:
bs = value.to_bytes(2, byteorder='little')
self.space[s - 1] = bs[0]
self.space[s] = bs[1]
self.S -= size
def stack_pop(self, size=1):
# S其实是个偏移量,栈空间存从第一页开始
s = self.S + 256
if size == 1:
value = self.space[s + 1]
if size == 2:
bs = self.space[s + 1:s + 3]
value = bytes_to_int(bs)
self.S += size
return value
def check_NMI(self):
PPUCTRL = self.space[0x2000]
if PPUCTRL >> 7 == 1:
log('NMI')
self.NMI()
class CpuSpace:
def __init__(self, size=64):
self.space = [0] * size * 1024
self.ppu = fc_ppu.PPU()
self.gamepad = fc_gamepad.Gamepad()
def __getitem__(self, index):
space = self.space
ppu = self.ppu
gamepad = self.gamepad
if isinstance(index, int):
if index == 0x2000:
# 返回 FlagByte
r = ppu.get_PPUCTRL()
elif index == 0x2002:
r = ppu.get_PPUSTATUS()
elif index in [0x2005, 0x2006]:
raise IndexError("index not allow get.only set")
elif index == 0x2007:
r = ppu.get_PPUDATA()
elif index == 0x4016:
r = gamepad.cpu_load()
else:
r = space[index]
elif isinstance(index, slice):
start = index.start
stop = index.stop
r = space[start:stop]
else:
raise IndexError("index error")
return r
def __setitem__(self, index, value):
space = self.space
ppu = self.ppu
if isinstance(index, int):
if index == 0x2000:
# 此处只改变值。位操作,需要另外实现。
ppu.set_PPUCTRL(value)
elif index == 0x2002:
ppu.set_PPUSTATUS(value)
elif index == 0x2006:
ppu.set_PPUADDR(value)
elif index == 0x2007:
ppu.set_PPUDATA(value)
elif index == 0x4014:
# 涉及cpu空间,不方便封在ppu里
ppu.registers['OAMDMA'] = value
copy_data = space[value * 0x100 : (value+1) * 0x100]
self.ppu.OAM = copy_data
elif index == 0x4016:
# CPU不会修改手柄的按键状态
pass
else:
space[index] = value
elif isinstance(index, slice):
start = index.start
stop = index.stop
space[start:stop] = value
else:
raise IndexError("index error")
def dumps(self):
d = {}
allow_attr = ['space']
for attr_name in allow_attr:
d[attr_name] = getattr(self, attr_name)
j = json.dumps(d)
with open('save/cpu_space_save.json', 'w') as f:
f.write(j)
def loads(self):
with open('save/cpu_space_save.json') as f:
data = f.read()
d = json.loads(data)
for name, value in d.items():
setattr(self, name, value)
def load_nes(name='nestest.nes'):
path = os.path.join('nes', name)
with open(path, 'rb') as f:
b = f.read()
prg_rom_size = b[4] # 单位16kb
chr_rom_size = b[5] # 单位8kb
flag6 = b[6]
flag7 = b[7]
# 8-15: byte 保留用, 应该为0. 其实有些在用了, 目前不管