class Chip8(object):
def __init__(self):
self.debug = False
# program counter
self.pc = 0
# register used to store memory address, 16-bit
self.I = None
# Initialize the Arithmetic logic unit
self.opcode_executor = OpcodeExecutor(self)
# 8-bit storage
self.sound_timer = None
self.is_running = False
# 8-bit storage
self.delay_timer = None
# 8-bit storage
self.stack_pointer = None
# set of hex characters for representing
# some characters
self.hex_chars = [
0xF0,
0x90,
0x90,
0x90,
0xF0, # 0
0x20,
0x60,
0x20,
0x20,
0x70, # 1
0xF0,
0x10,
0xF0,
0x80,
0xF0, # 2
0xF0,
0x10,
0xF0,
0x10,
0xF0, # 3
0x90,
0x90,
0xF0,
0x10,
0x10, # 4
0xF0,
0x80,
0xF0,
0x10,
0xF0, # 5
0xF0,
0x80,
0xF0,
0x90,
0xF0, # 6
0xF0,
0x10,
0x20,
0x40,
0x40, # 7
0xF0,
0x90,
0xF0,
0x90,
0xF0, # 8
0xF0,
0x90,
0xF0,
0x10,
0xF0, # 9
0xF0,
0x90,
0xF0,
0x90,
0x90, # A
0xE0,
0x90,
0xE0,
0x90,
0xE0, # B
0xF0,
0x80,
0x80,
0x80,
0xF0, # C
0xE0,
0x90,
0x90,
0x90,
0xE0, # D
0xF0,
0x80,
0xF0,
0x80,
0xF0, # E
0xF0,
0x80,
0xF0,
0x80,
0x80 # F
]
def initialize(self):
self.pc = 0x200
self.step = 0
self.I = 0
self.keys = [0 for i in xrange(16)]
self.sound_timer = 0
self.memory = [0 for i in xrange(4095)]
self.delay_timer = 0
self.stack_pointer = 0
self.display_width = 64
self.display_height = 32
self.draw_flag = False
self.display = [
0 for i in xrange(self.display_width * self.display_height)
]
# registers 8-bit
self.Vx = [0 for i in xrange(16)]
# 16-bit long stack
self.stack = []
for i, chars in enumerate(self.hex_chars):
self.memory[i] = chars
def load_program(self, program):
"""
Load the program into memory
"""
self.log("Load the program into memory")
for i, chars in enumerate(program):
self.memory[0x200 + i] = chars
def log(self, msg):
if self.debug:
print msg
def clear_screen(self):
"""
Clear the display
"""
self.log("Clear the display")
self.renderer.clear_display()
for i, j in enumerate(self.display):
self.display[i] = 0
def set_renderer(self, renderer):
"""
Set the display output
"""
self.renderer = renderer
def set_display(self, dx, dy):
"""
Handle the logic for setting the display
"""
self.log("Set the display")
if dx > self.display_width:
dx -= self.display_width
elif dx < 0:
dx += self.display_width
if dy > self.display_height:
dy -= self.display_height
elif dy < 0:
dy += self.display_height
self.display[dx + (dy * self.display_width)] ^= 1
def key_pressed(self, key):
self.keys[key] = True
def key_realeased(self, key):
self.keys[key] = False
def continue_cycle(self, key):
"""
Continue cycle after pause
"""
self.Vx[self.x] = key
self.emulate_cpu()
def stop_cycle(self):
self.is_running = False
def emulate_cpu(self):
self.log("Emulate Cpu")
self.is_running = True
while True:
if self.is_running:
self.start_cycle()
if self.draw_flag:
self.renderer.draw_graphics(self.display)
self.draw_flag = False
if self.delay_timer > 0:
self.delay_timer -= 1
if self.sound_timer > 0:
self.sound_timer -= 1
def start_cycle(self):
"""
Start the cpu execution cycle, this is the point where
the opcodes are analyzed
"""
self.log("Start cycle")
opcode = (self.memory[self.pc] << 8) | self.memory[self.pc + 1]
self.x = (opcode & 0x0f00) >> 8
self.y = (opcode & 0x00f0) >> 4
self.pc += 2
self.opcode_executor.execute_opcode(opcode, self.x, self.y)
def __init__(self):
self.debug = False
# program counter
self.pc = 0
# register used to store memory address, 16-bit
self.I = None
# Initialize the Arithmetic logic unit
self.opcode_executor = OpcodeExecutor(self)
# 8-bit storage
self.sound_timer = None
self.is_running = False
# 8-bit storage
self.delay_timer = None
# 8-bit storage
self.stack_pointer = None
# set of hex characters for representing
# some characters
self.hex_chars = [
0xF0,
0x90,
0x90,
0x90,
0xF0, # 0
0x20,
0x60,
0x20,
0x20,
0x70, # 1
0xF0,
0x10,
0xF0,
0x80,
0xF0, # 2
0xF0,
0x10,
0xF0,
0x10,
0xF0, # 3
0x90,
0x90,
0xF0,
0x10,
0x10, # 4
0xF0,
0x80,
0xF0,
0x10,
0xF0, # 5
0xF0,
0x80,
0xF0,
0x90,
0xF0, # 6
0xF0,
0x10,
0x20,
0x40,
0x40, # 7
0xF0,
0x90,
0xF0,
0x90,
0xF0, # 8
0xF0,
0x90,
0xF0,
0x10,
0xF0, # 9
0xF0,
0x90,
0xF0,
0x90,
0x90, # A
0xE0,
0x90,
0xE0,
0x90,
0xE0, # B
0xF0,
0x80,
0x80,
0x80,
0xF0, # C
0xE0,
0x90,
0x90,
0x90,
0xE0, # D
0xF0,
0x80,
0xF0,
0x80,
0xF0, # E
0xF0,
0x80,
0xF0,
0x80,
0x80 # F
]
