git.y1.nz

commit f5965fda2263ab6e15d9a7342d7343d3c91e0b98
parent 3d87c5c92a3bb48d35f909286d224d8268d778a1
Author: Lior Halphon <LIJI32@gmail.com>
Date:   Mon, 22 Dec 2025 22:46:05 +0200

Handle an edge case more accurately

Diffstat:
M
Core/apu.c
8
++++----

1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/Core/apu.c b/Core/apu.c
@@ -1365,10 +1365,6 @@ static void prepare_noise_start(GB_gameboy_t *gb)
             if ((gb->io_registers[GB_IO_NR43] & 0xf0) == 0x10 && (gb->apu.noise_channel.counter & 1)) {
                 instant_step = true;
             }
-            if (gb->apu.noise_channel.did_step_counter) {
-                gb->apu.noise_channel.counter++;
-                gb->apu.noise_channel.counter &= 0x3FFF;
-            }
             /* TODO: needs further research, the conditions are very odd. What if NR43 changes before stepping? */
             if ((gb->io_registers[GB_IO_NR43] & 0xf0) == 0x10 && !gb->apu.noise_channel.did_step_counter) {
                 div_1_glitch = true;
@@ -1418,6 +1414,10 @@ static void prepare_noise_start(GB_gameboy_t *gb)
             else if (divisor > 1 && (!gb->cgb_double_speed || gb->model > GB_MODEL_CGB_C)) {
                 gb->apu.noise_channel.counter_countdown -= 4;
             }
+            /* TODO: This quirk seems way too specific */
+            else if (divisor == 1 && gb->apu.is_active[GB_NOISE] && !(gb->io_registers[GB_IO_NR43] & 0xf0)) {
+                gb->apu.noise_channel.counter_countdown -= 4;
+            }
         }
         else if (gb->cgb_double_speed && gb->model <= GB_MODEL_CGB_C) {
             gb->apu.noise_channel.counter_countdown += 2;

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