From dae509f7c02c443ba58a662f659785c470c7b358 Mon Sep 17 00:00:00 2001
From: Tatsuya Fujita <tfujita@gmail.com>
Date: Sat, 7 Dec 2024 15:14:15 +0900
Subject: [PATCH] Workaround for "Sonic & Kuckles All  Emeralds"

---
 lib/fm/fm.cpp |  1 +
 src/common.h  |  1 +
 src/main.cpp  |  2 +-
 src/vgm.cpp   | 15 +++++++++------
 4 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/fm/fm.cpp b/lib/fm/fm.cpp
index 40d7b82..b37ca01 100644
--- a/lib/fm/fm.cpp
+++ b/lib/fm/fm.cpp
@@ -129,6 +129,7 @@ void FMChip::writeRaw(byte data, byte chipno, si5351Freq_t freq) {
   // 3.579MHz :  0.2794us * 32 = 8.94 us
   // 1.5MHz   :  0.66us   * 32 = 21.3 us
   WR_LOW;
+
   ets_delay_us((32000000 / freq));
 
   WR_HIGH;
diff --git a/src/common.h b/src/common.h
index ea3d474..9b13760 100644
--- a/src/common.h
+++ b/src/common.h
@@ -8,6 +8,7 @@
 
 #define USE_YM2612
 #define USE_SN76489
+#define USE_YM2203
 
 #define CHIP0_CLOCK CLK_0
 #define CHIP1_CLOCK CLK_1
diff --git a/src/main.cpp b/src/main.cpp
index 4ee129e..d359b9f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -64,7 +64,7 @@ void setup() {
   lcd.setFont(&fonts::Font2);
   lcd.println("NANO DRIVE 6");
   lcd.println("2024 Fujix@e2j.net");
-  lcd.printf("Firmware: 1.82\n\n");
+  lcd.printf("Firmware: 1.83\n\n");
 
   // PSRAM 初期化確認
   if (psramInit()) {
diff --git a/src/vgm.cpp b/src/vgm.cpp
index b826a75..81f6a97 100644
--- a/src/vgm.cpp
+++ b/src/vgm.cpp
@@ -80,13 +80,11 @@ bool VGM::ready() {
 
   // version
   version = get_ui32_at(8);
-
   // total # samples
   // totalSamples = get_ui32_at(0x18);
 
   // loop offset
   loopOffset = get_ui32_at(0x1c);
-
   // vg3 offset
   gd3Offset = get_ui32_at(0x14) + 0x14;
 
@@ -644,10 +642,15 @@ void VGM::vgmProcessMain() {
       break;
 
     case 0x50:  // SN76489 CHIP 1
-      if (SN76489_Freq0is0X400) {
-        FM.writeRaw(get_ui8(), 1, freq[chipSlot[CHIP_SN76489_0]]);
-      } else {
-        FM.write(get_ui8(), 1, freq[chipSlot[CHIP_SN76489_0]]);
+
+      // WORKAROUND FOR COMMAND TO UNDEFINED SN CHIP
+      // Sonic & Knuckles 30th song
+      if (freq[chipSlot[CHIP_SN76489_0]] != SI5351_UNDEFINED) {
+        if (SN76489_Freq0is0X400) {
+          FM.writeRaw(get_ui8(), 1, freq[chipSlot[CHIP_SN76489_0]]);
+        } else {
+          FM.write(get_ui8(), 1, freq[chipSlot[CHIP_SN76489_0]]);
+        }
       }
       break;
 #endif