Skip to content

Add Bitplane Control #40

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jul 2, 2024
Merged

Add Bitplane Control #40

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions README.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -314,8 +314,8 @@ Color values are specified by using HTML hex values such as `AABBCC` without the
leading `#`. There are currently 4 color values that can be set:

* `--color_0` specifies the background color. This defaults to `000000`.
* `--color_1` specifies bitplane 1 color. This defaults to `666666`.
* `--color_2` specifies bitplane 2 color. This defaults to `BBBBBB`.
* `--color_1` specifies bitplane 1 color. This defaults to `FF33CC`.
* `--color_2` specifies bitplane 2 color. This defaults to `33CCFF`.
* `--color_3` specifies bitplane 1 and 2 overlap color. This defaults to `FFFFFF`.

For Chip8 and SuperChip 8 programs, only the background color `color_0` (for pixels
Expand Down
170 changes: 95 additions & 75 deletions chip8/cpu.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -114,7 +114,7 @@ def __init__(
0x2: self.jump_to_subroutine, # 2nnn - CALL nnn
0x3: self.skip_if_reg_equal_val, # 3snn - SKE Vs, nn
0x4: self.skip_if_reg_not_equal_val, # 4snn - SKNE Vs, nn
0x5: self.skip_if_reg_equal_reg, # 5st0 - SKE Vs, Vt
0x5: self.save_skip_routines, # see subfunctions below
0x6: self.move_value_to_reg, # 6snn - LOAD Vs, nn
0x7: self.add_value_to_reg, # 7snn - ADD Vs, nn
0x8: self.execute_logical_instruction, # see subfunctions below
Expand All @@ -127,6 +127,12 @@ def __init__(
0xF: self.misc_routines, # see subfunctions below
}

self.save_skip_lookup = {
0x0: self.skip_if_reg_equal_reg, # 5xy0 - SKE Vx, Vy
0x2: self.store_subset_regs_in_memory, # 5xy2 - STORSUB x, y
0x3: self.read_subset_regs_in_memory, # 5xy3 - LOADSUB x, y
}

self.clear_routines = {
0xE0: self.clear_screen, # 00E0 - CLS
0xEE: self.return_from_subroutine, # 00EE - RTS
Expand Down Expand Up @@ -257,21 +263,25 @@ def keyboard_routines(self):
if self.memory[self.pc - 2] == 0xF0 and self.memory[self.pc - 1] == 0x00:
self.pc += 2

def save_skip_routines(self):
"""
Will execute either a register save or skip routine.
"""
operation = self.operand & 0x000F
try:
self.save_skip_lookup[operation]()
except KeyError:
raise UnknownOpCodeException(self.operand)

def misc_routines(self):
"""
Will execute one of the routines specified in misc_routines.
"""
operation = self.operand & 0x00FF
sub_operation = self.operand & 0x000F
if sub_operation == 0x2:
self.store_subset_regs_in_memory()
elif sub_operation == 0x3:
self.read_subset_regs_in_memory()
else:
try:
self.misc_routine_lookup[operation]()
except KeyError:
raise UnknownOpCodeException(self.operand)
try:
self.misc_routine_lookup[operation]()
except KeyError:
raise UnknownOpCodeException(self.operand)

def clear_return(self):
"""
Expand All @@ -282,7 +292,7 @@ def clear_return(self):
sub_operation = operation & 0x00F0
if sub_operation == 0x00C0:
num_lines = self.operand & 0x000F
self.screen.scroll_down(num_lines)
self.screen.scroll_down(num_lines, self.bitplane)
self.last_op = f"Scroll Down {num_lines:01X}"
else:
try:
Expand All @@ -296,7 +306,7 @@ def clear_screen(self):

Clears the screen
"""
self.screen.clear_screen()
self.screen.clear_screen(self.bitplane)
self.last_op = "CLS"

def return_from_subroutine(self):
Expand All @@ -318,7 +328,7 @@ def scroll_right(self):

Scrolls the screen right by 4 pixels.
"""
self.screen.scroll_right()
self.screen.scroll_right(self.bitplane)
self.last_op = "Scroll Right"

def scroll_left(self):
Expand All @@ -327,7 +337,7 @@ def scroll_left(self):

Scrolls the screen left by 4 pixels.
"""
self.screen.scroll_left()
self.screen.scroll_left(self.bitplane)
self.last_op = "Scroll Left"

def exit(self):
Expand Down Expand Up @@ -450,6 +460,58 @@ def skip_if_reg_equal_reg(self):
self.pc += 2
self.last_op = f"SKE V{x:01X}, V{y:01X}"

def store_subset_regs_in_memory(self):
"""
5xy2 - STORSUB [I], Vx, Vy

Store a subset of registers from x to y in memory starting at index.
The x and y calculation is as follows:

Bits: 15-12 11-8 7-4 3-0
F x y 2

If x is larger than y, then they will be stored in reverse order.
"""
x = (self.operand & 0x0F00) >> 8
y = (self.operand & 0x00F0) >> 4
pointer = 0
if y >= x:
for z in range(x, y+1):
self.memory[self.index + pointer] = self.v[z]
pointer += 1
else:
for z in range(x, y-1, -1):
self.memory[self.index + pointer] = self.v[z]
pointer += 1

self.last_op = f"STORSUB [I], {x:01X}, {y:01X}"

def read_subset_regs_in_memory(self):
"""
5xy3 - LOADSUB [I], Vx, Vy

Load a subset of registers from x to y in memory starting at index.
The x and y calculation is as follows:

Bits: 15-12 11-8 7-4 3-0
F x y 2

If x is larger than y, then they will be loaded in reverse order.
"""
x = (self.operand & 0x0F00) >> 8
y = (self.operand & 0x00F0) >> 4
pointer = 0
if y >= x:
for z in range(x, y+1):
self.v[z] = self.memory[self.index + pointer]
pointer += 1
else:
for z in range(x, y-1, -1):
self.v[z] = self.memory[self.index + pointer]
pointer += 1

self.last_op = f"LOADSUB [I], {x:01X}, {y:01X}"

def move_value_to_reg(self):
"""
6xnn - LOAD Vx, nn
Expand Down Expand Up @@ -781,19 +843,28 @@ def draw_sprite(self):
self.v[0xF] = 0

if num_bytes == 0:
self.draw_extended(x_pos, y_pos)
if self.bitplane == 3:
self.draw_extended(x_pos, y_pos, 1)
self.draw_extended(x_pos, y_pos, 2)
else:
self.draw_extended(x_pos, y_pos, self.bitplane)
self.last_op = f"DRAWEX"
else:
self.draw_normal(x_pos, y_pos, num_bytes)
if self.bitplane == 3:
self.draw_normal(x_pos, y_pos, num_bytes, 1)
self.draw_normal(x_pos, y_pos, num_bytes, 2)
else:
self.draw_normal(x_pos, y_pos, num_bytes, self.bitplane)
self.last_op = f"DRAW V{x_source:01X}, V{y_source:01X}"

def draw_normal(self, x_pos, y_pos, num_bytes):
def draw_normal(self, x_pos, y_pos, num_bytes, bitplane):
"""
Draws a sprite on the screen while in NORMAL mode.

:param x_pos: the X position of the sprite
:param y_pos: the Y position of the sprite
:param num_bytes: the number of bytes to draw
:param bitplane: the bitplane to draw to
"""
for y_index in range(num_bytes):
color_byte = self.memory[self.index + y_index]
Expand All @@ -806,13 +877,13 @@ def draw_normal(self, x_pos, y_pos, num_bytes):
if not self.clip_quirks or (self.clip_quirks and x_coord < self.screen.get_width()):
x_coord = x_coord % self.screen.get_width()
turned_on = (color_byte & mask) > 0
current_on = self.screen.get_pixel(x_coord, y_coord)
current_on = self.screen.get_pixel(x_coord, y_coord, bitplane)
self.v[0xF] |= 1 if turned_on and current_on else 0
self.screen.draw_pixel(x_coord, y_coord, turned_on ^ current_on)
self.screen.draw_pixel(x_coord, y_coord, turned_on ^ current_on, bitplane)
mask = mask >> 1
self.screen.update()

def draw_extended(self, x_pos, y_pos):
def draw_extended(self, x_pos, y_pos, bitplane):
"""
Draws a sprite on the screen while in EXTENDED mode. Sprites in this
mode are assumed to be 16x16 pixels. This means that two bytes will
Expand All @@ -821,6 +892,7 @@ def draw_extended(self, x_pos, y_pos):

:param x_pos: the X position of the sprite
:param y_pos: the Y position of the sprite
:param bitplane: the bitplane to draw to
"""
for y_index in range(16):
for x_byte in range(2):
Expand All @@ -834,9 +906,9 @@ def draw_extended(self, x_pos, y_pos):
if not self.clip_quirks or (self.clip_quirks and x_coord < self.screen.get_width()):
x_coord = x_coord % self.screen.get_width()
turned_on = (color_byte & mask) > 0
current_on = self.screen.get_pixel(x_coord, y_coord)
current_on = self.screen.get_pixel(x_coord, y_coord, bitplane)
self.v[0xF] += 1 if turned_on and current_on else 0
self.screen.draw_pixel(x_coord, y_coord, turned_on ^ current_on)
self.screen.draw_pixel(x_coord, y_coord, turned_on ^ current_on, bitplane)
mask = mask >> 1
else:
self.v[0xF] += 1
Expand Down Expand Up @@ -873,58 +945,6 @@ def set_bitplane(self):
self.bitplane = (self.operand & 0x0F00) >> 8
self.last_op = f"BITPLANE {self.bitplane:01X}"

def store_subset_regs_in_memory(self):
"""
Fxy2 - STORSUB [I], Vx, Vy

Store a subset of registers from x to y in memory starting at index.
The x and y calculation is as follows:

Bits: 15-12 11-8 7-4 3-0
F x y 2

If x is larger than y, then they will be stored in reverse order.
"""
x = (self.operand & 0x0F00) >> 8
y = (self.operand & 0x00F0) >> 4
pointer = 0
if y >= x:
for z in range(x, y+1):
self.memory[self.index + pointer] = self.v[z]
pointer += 1
else:
for z in range(x, y-1, -1):
self.memory[self.index + pointer] = self.v[z]
pointer += 1

self.last_op = f"STORSUB [I], {x:01X}, {y:01X}"

def read_subset_regs_in_memory(self):
"""
Fxy3 - LOADSUB [I], Vx, Vy

Load a subset of registers from x to y in memory starting at index.
The x and y calculation is as follows:

Bits: 15-12 11-8 7-4 3-0
F x y 2

If x is larger than y, then they will be loaded in reverse order.
"""
x = (self.operand & 0x0F00) >> 8
y = (self.operand & 0x00F0) >> 4
pointer = 0
if y >= x:
for z in range(x, y+1):
self.v[z] = self.memory[self.index + pointer]
pointer += 1
else:
for z in range(x, y-1, -1):
self.v[z] = self.memory[self.index + pointer]
pointer += 1

self.last_op = f"LOADSUB [I], {x:01X}, {y:01X}"

def move_delay_timer_into_reg(self):
"""
Fx07 - LOAD Vx, DELAY
Expand Down
Loading
Loading