From 40b7e2512640952e8559829d9ae96a0762da778c Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Wed, 10 May 2023 00:55:04 +0300
Subject: [PATCH] Accurate emulation of SVBK, fixes audio in Flyeyes
 (unlicensed game)

---
 Core/memory.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Core/memory.c b/Core/memory.c
index 723cd18..b1f61c9 100644
--- a/Core/memory.c
+++ b/Core/memory.c
@@ -665,7 +665,8 @@ static uint8_t read_high_memory(GB_gameboy_t *gb, uint16_t addr)
                 if (!gb->cgb_mode) {
                     return 0xFF;
                 }
-                return gb->cgb_ram_bank | ~0x7;
+
+                return gb->io_registers[GB_IO_SVBK];
             case GB_IO_VBK:
                 if (!GB_is_cgb(gb)) {
                     return 0xFF;
@@ -1593,6 +1594,7 @@ static void write_high_memory(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
                     if (!gb->cgb_ram_bank) {
                         gb->cgb_ram_bank++;
                     }
+                    gb->io_registers[GB_IO_SVBK] = value | ~0x7;
                 }
                 return;
             case GB_IO_VBK: