irdcat / wasm-invaders

Space invaders arcade machine emulator (intel8080 cpu & peripherials) compiled to WebAssembly

wasm-invaders's Issues

TEST8080.COM fails during testing SBI instruction

PC: 026A AF: F056 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 0 P: 1 AC: 1 Z: 1 S: 0} Cycles: 545     

SBI F1

PC: 026C AF: FF86 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 0 P: 1 AC: 0 Z: 0 S: 1} Cycles: 552     

SBI E

PC: 026E AF: F193 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 1 P: 0 AC: 1 Z: 0 S: 1} Cycles: 559     

CPI F0

PC: 0270 AF: F112 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 0 P: 0 AC: 1 Z: 0 S: 0} Cycles: 566     

JZ 276

PC: 0273 AF: F112 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 0 P: 0 AC: 1 Z: 0 S: 0} Cycles: 576

ASM code:

SBII:   SBI 0F1H    ;A=F0H-0F1H-CARRY(0)=FFH,C=1
        SBI 00EH    ;A=FFH-OEH-CARRY(1)=F0H,C=0
        CPI 0F0H
        JZ  ANII    ;TEST "SBI"
        CALL    CPUER

Update Readme with information about finished emulator

Implement ability to import/export hi-score data

Hi-score made during run instance of an emulator are stored in RAM at address 20F4.
Before drawing status bar, game copies existing hi-score from address 1BF4.

So functionality should work in that way:

• To import hi-score, value should be stored at address 1BF4.
• To export hi-score, value should be taken from 20F4.

Improvements to UI

Arithmetic instructions with register operand are adding too much cycles to the counter

PC: 05B3 AF: 5556 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 0 P: 1 AC: 1 Z: 1 S: 0} Cycles: 4622    

ORA A

PC: 05B4 AF: 5506 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 0 P: 1 AC: 0 Z: 0 S: 0} Cycles: 4633

ORA A should add 4 cycles instead of 11.

Get rid of c++ exceptions

Rather than throwing exception, display message inside document

Switch to CMake build system

TST8080 fails on SHLD and LHLD instructions test.

Black screen after emulator startup

Main loop seems to go without problems, however there's nothing on the screen.

DAA instruction does not work properly

PC: 05B4 AF: 5506 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 0 P: 1 AC: 0 Z: 0 S: 0} Cycles: 4633    

DAA

PC: 05B5 AF: 0046 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 0 P: 1 AC: 0 Z: 1 S: 0} Cycles: 4637    

CPI 55

PC: 05B7 AF: 0083 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 1 P: 0 AC: 0 Z: 0 S: 1} Cycles: 4644

ASM code:

        DAA
        CPI 055H
        CNZ CPUER   ;TEST "DAA"

Github pages

DAA instruction works improperly when both flags are set

PC: 05BD AF: 1013 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 1 P: 0 AC: 1 Z: 0 S: 0} Cycles: 3854    

DAA

PC: 05BE AF: 7707 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 1 P: 1 AC: 0 Z: 0 S: 0} Cycles: 3858    

CPI 76

PC: 05C0 AF: 7712 BC: FFFF DE: 3333 HL: DDDD SP: 07BD Flags: { C: 0 P: 0 AC: 1 Z: 0 S: 0} Cycles: 3865    

CNZ 6A0

PC: 06A0 AF: 7712 BC: FFFF DE: 3333 HL: DDDD SP: 07BB Flags: { C: 0 P: 0 AC: 1 Z: 0 S: 0} Cycles: 3882

ASM code

        DAA
        CPI 076H
        CNZ CPUER   ;TEST "DAA"

Exception is thrown after pushing SDL_QUIT event to the event queue.

Following exception can be found in the browser console.

Uncaught TypeError: Cannot read properties of undefined (reading 'deleteTexture')
    at _emscripten_glDeleteTextures (wasm-invaders.js:6202:15)
    at imports.<computed> (wasm-invaders.js:8814:35)
    at GLES2_DestroyTexture (wasm-invaders.wasm:0x11cc16)
    at SDL_DestroyTexture (wasm-invaders.wasm:0x109922)
    at decltype(std::declval<void (*&)(SDL_Texture*)>()(std::declval<SDL_Texture*>())) std::__2::__invoke[abi:v15006]<void (*&)(SDL_Texture*), SDL_Texture*>(void (*&)(SDL_Texture*), SDL_Texture*&&) (wasm-invaders.wasm:0x70942)
    at void std::__2::__invoke_void_return_wrapper<void, true>::__call<void (*&)(SDL_Texture*), SDL_Texture*>(void (*&)(SDL_Texture*), SDL_Texture*&&) (wasm-invaders.wasm:0x70757)
    at std::__2::__function::__alloc_func<void (*)(SDL_Texture*), std::__2::allocator<void (*)(SDL_Texture*)>, void (SDL_Texture*)>::operator()[abi:v15006](SDL_Texture*&&) (wasm-invaders.wasm:0x6eae5)
    at std::__2::__function::__func<void (*)(SDL_Texture*), std::__2::allocator<void (*)(SDL_Texture*)>, void (SDL_Texture*)>::operator()(SDL_Texture*&&) (wasm-invaders.wasm:0x6e912)
    at std::__2::__function::__value_func<void (SDL_Texture*)>::operator()[abi:v15006](SDL_Texture*&&) const (wasm-invaders.wasm:0x4df17)
    at std::__2::function<void (SDL_Texture*)>::operator()(SDL_Texture*) const (wasm-invaders.wasm:0x4da58)

Cpu incorrectly jumps to address 0xDC18

Instead it should jump back to 0x18DC to CALL DrawStatus subroutine

init:
LD      SP,$2400            ; Set stack pointer just below screen
LD      B,$00               ; Count 256 bytes
CALL    $01E6               ; Copy ROM to RAM
CALL    DrawStatus          ; Print scores and credits

Replace emscripten generated UI with custom one

Playing audio in the emulator

Find workaround for broken sound effects

Workaround have to be found for following problems:

• Explosion after player dies is played twice
• Shooting sound is played two or even three times depending on how long projectile is in the air
• Original hardware seemed to allow overlapping of ufo flying sound to a certain extent

It probably has something to do how original hardware handled specific sounds.

CPI 0 instruction in TEST8080.COM does not reset Carry flag.

According to the execution log, carry flag is not reset after executing CPI 0.

// State before execution
PC: 0237 AF: F597 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 1 P: 1 AC: 1 Z: 0 S: 1} Cycles: 402     

CPI 0

// State after execution
PC: 0239 AF: F587 BC: 0009 DE: 0000 HL: 0000 SP: 07BD Flags: { C: 1 P: 1 AC: 0 Z: 0 S: 1} Cycles: 409

ASM code fragment:

;
;TEST ACCUMULATOR IMMEDIATE INSTRUCTIONS
;
AIMM:   CPI 0   ;A=F5H,C=0,Z=0
        JC  CPIE    ;TEST "CPI" FOR RE-SET CARRY
        JZ  CPIE    ;TEST "CPI" FOR RE-SET ZERO
        CPI 0F5H    ;A=F5H,C=0,Z=1
        JC  CPIE    ;TEST "CPI" FOR RE-SET CARRY ("ADI")
        JNZ CPIE    ;TEST "CPI" FOR RE-SET ZERO
        CPI 0FFH    ;A=F5H,C=1,Z=0
        JZ  CPIE    ;TEST "CPI" FOR RE-SET ZERO
        JC  ACII    ;TEST "CPI" FOR SET CARRY
CPIE:   CALL    CPUER

Introduce Unit Tests

Multiple display bugs after passing initial Title Screen

Shooting sound is played twice if projectile flies long enough

All pixels are incorrectly rendered red

Should be red, white and green depending on the coordinate of the pixel

Cpu is stuck in the loop of the ClearScreen procedure

Cpu seems to be stuck in the procedure

ClearScreen:
LD      HL,$2400            ; Screen coordinate
LD      (HL),$00            ; Clear it
INC     HL                  ; Next byte
LD      A,H                 ; Have we done ...
CP      $40                 ; ... all the screen?
JP      NZ,$1A5F            ; No ... keep going
RET                         ; Out