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with Ada.Command_Line;
with Ada.Numerics.Discrete_Random;
with Ada.Text_IO;
with Sf;
with Sf.Audio;
with Sf.Audio.Sound;
with Sf.Audio.SoundBuffer;
with ISA;
with CPU;
with Video;
procedure Ada_Chip is
package Random_Byte is new Ada.Numerics.Discrete_Random (ISA.Byte);
Random_Generator : Random_Byte.Generator;
State : CPU.Instance;
Delay_Timer : Natural := 0;
Sound_Timer : Natural := 0;
procedure Draw_Sprite (VX, VY : ISA.Register_Index; N : ISA.Byte) is
use ISA;
X : constant Byte := State.Registers (VX);
Y : constant Byte := State.Registers (VY);
Row : aliased Byte;
Row_Pixels : Pixel with Address => Row'Address;
VF : Byte := 0;
begin
for I in 0 .. N - 1 loop
Row := State.Memory (State.Address_Register + Address (I));
for J in 0 .. 7 loop
if Row_Pixels (7 - J) then
if Video.Toggle_Pixel
(Sf.sfUint32 ((X + Byte (J)) mod Video.Width),
Sf.sfUint32 ((Y + I) mod Video.Height))
then
VF := 1;
end if;
end if;
end loop;
end loop;
State.Registers (15) := VF;
end Draw_Sprite;
procedure Run_Flow (ins : ISA.Opcode) is
begin
case ins.Value is
when ISA.Clear_Screen => Video.Clear_Screen;
when ISA.Ret => CPU.Ret (State);
when others => begin
Ada.Text_IO.Put_Line ("Machine code calls are unsupported!");
delay 1.0;
Video.Finish;
end;
end case;
end Run_Flow;
procedure Run_Input (ins : ISA.Opcode) is
use ISA;
Key : constant Video.Key := Video.Key
(State.Registers (X_Register (ins)) mod 16);
begin
case Input_Class'Enum_Val (To_Byte (ins)) is
when Key_Down =>
if Video.Key_Down (Key) then
CPU.Skip (State);
end if;
when Key_Up =>
if Video.Key_Up (Key) then
CPU.Skip (State);
end if;
end case;
end Run_Input;
procedure Run_Misc (ins : ISA.Opcode) is
use ISA;
X : constant Register_Index := X_Register (ins);
begin
case Misc_Class'Enum_Val (To_Byte (ins)) is
when Get_Delay => State.Registers (X) := Byte (Delay_Timer);
when Get_Key => State.Registers (X) := Byte (Video.Next_Key);
when Set_Delay => Delay_Timer := Natural (State.Registers (X));
when Set_Sound => Sound_Timer := Natural (State.Registers (X));
when Reg_Store => CPU.Reg_Store (State, X);
when Reg_Load => CPU.Reg_Load (State, X);
when Add_Address => State.Address_Register :=
State.Address_Register + Address (State.Registers (X));
when Get_Font =>
State.Address_Register := Address (State.Registers (X) mod 16) * 5;
when Get_BCD => begin
State.Memory (State.Address_Register) :=
State.Registers (X) / 100;
State.Memory (State.Address_Register + 1) :=
State.Registers (X) / 10 mod 10;
State.Memory (State.Address_Register + 2) :=
State.Registers (X) mod 10;
end;
end case;
end Run_Misc;
procedure Run_Step is
use ISA;
ins : constant Opcode := CPU.Get_Opcode (State);
XI : constant Register_Index := X_Register (ins);
YI : constant Register_Index := Y_Register (ins);
X : constant Byte := State.Registers (XI);
Y : constant Byte := State.Registers (YI);
begin
case ins.Class is
when Flow => Run_Flow (ins);
when Jump => CPU.Jump (State, Address (ins.Value));
when Call => CPU.Call (State, Address (ins.Value));
when Set_Register => State.Registers (XI) := To_Byte (ins);
when Add => State.Registers (XI) := X + To_Byte (ins);
when Math => CPU.Math (State, XI, YI, To_Byte (ins) mod 16);
when Set_Address => State.Address_Register := Address (ins.Value);
when Draw_Sprite => Draw_Sprite (XI, YI, To_Byte (ins) mod 16);
when Input => Run_Input (ins);
when Misc => Run_Misc (ins);
when Jump_Relative =>
CPU.Jump (State,
Address (State.Registers (0)) + Address (ins.Value));
when Equal =>
if X = To_Byte (ins) then
CPU.Skip (State);
end if;
when Not_Equal =>
if X /= To_Byte (ins) then
CPU.Skip (State);
end if;
when Compare =>
if X = Y then
CPU.Skip (State);
end if;
when Not_Compare =>
if X /= Y then
CPU.Skip (State);
end if;
when Random =>
State.Registers (XI) :=
Random_Byte.Random (Random_Generator) mod To_Byte (ins);
end case;
end Run_Step;
Steps_Per_Frame : constant := 8;
Beep_Sound : constant Sf.Audio.sfSound_Ptr := Sf.Audio.Sound.create;
Beep_Sound_Buffer : constant Sf.Audio.sfSoundBuffer_Ptr :=
Sf.Audio.SoundBuffer.createFromFile ("beep.ogg");
begin
if Ada.Command_Line.Argument_Count /= 1 then
Ada.Text_IO.Put_Line ("usage: adachip <.c8 file>");
else
Video.Initialize;
Random_Byte.Reset (Random_Generator);
CPU.Load_File (State, Ada.Command_Line.Argument (1));
Sf.Audio.Sound.setBuffer (Beep_Sound, Beep_Sound_Buffer);
while Video.Is_Running loop
Video.Display;
Video.Poll_Events;
if Delay_Timer > 0 then
Delay_Timer := Delay_Timer - 1;
end if;
if Sound_Timer > 0 then
Sf.Audio.Sound.play (Beep_Sound);
Sound_Timer := Sound_Timer - 1;
end if;
for I in 0 .. Steps_Per_Frame loop
Run_Step;
end loop;
end loop;
Sf.Audio.Sound.destroy (Beep_Sound);
end if;
end Ada_Chip;
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