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Speaking of Marble Madness, the glitched-text-box issue doesn't appear in my emulator, but there is another problem: a flickering on the top of the screen when the game starts.

I don't know the cause of the problem, but as I remember correctly, FCEUX doesn't produce any of the mentioned glitches.

https://wiki.nesdev.com/w/index.php/Emulator_tests Output at $6000 --------------- All text output is written starting at $6004, with a zero-byte terminator at the end. As more text is written, the terminator is moved forward, so an emulator can print the current text at any time. The test status i...

I don't understand something. In the second level of Battletoads, when I move the main character to the bottom of the screen, it becomes "immortal" because enemies always attack below the main character, despite his location. I've found, the problem is the time of rising the sprite overflo...

My emulator has passed all tests :o (not including nmi_and_irq and ppu_sprite_hit). I added the following lines into the write_mask function to pass 10-even_odd_timing: if ((mask ^ open_bus_data) & MASK_MASK_RENDERING_ENABLED) { if (scanline == 261 && clks == 339 && odd_frame) cl...

Hm. Now, I can't pass 3-nmi_and_irq.nes from cpu_interrupts_v2 and the last one from ppu_vbl_nmi (even_odd_timing). Does someone know, if APU works properly but not very accurate, can it cause my emulator to fail the nmi_and_irq test?

So, I've implemented some basics of the APU frame counter but it still doesn't work. Is it not enough for just running the tests? void write_frame_counter(unsigned v) noexcept { frame_counter_mode = FrameCounterMode(v >> 7); if ((inhibit_frame_irq = v & 0x40)) mem_pointers.cpu->set_irq(false); d...

My emulator supports all official instructions ( instr_test-v5 ) and basics of VBL handling ( ppu_vbl_nmi - single rom #1 ), but I have a problem with cpu_timing_test6 and branch_timing_tests test ROMs. Do they use any APU length counter? Because when my emulator executes these ROMs, they are stuck ...

Thank you for reply. Yes, I see. The problem was my emulator didn't correctly handle writing to LCDC. That was incorrect code: void GPU::write_lcd_control(unsigned value) noexcept { control = value; if (control & CONTROL_MASK_LCD_DISPLAY_ENABLE) { stat = (stat & ~STAT_MASK_MODE_FLAG) | STAT_...

Hello, I'm writing a Gameboy emulator and I ran into problems. Some time, each test rom (from cpu_instrs) that my emulator executes, writes to LCDC not during V-Blank period, which is bad. Are there knowledgeable people who can help me, is this problem of my emulator or not? UPDATE: I just have unde...