From 075f758e4dd65d7886d8e5f363cd7a05dfd49231 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 27 Mar 2022 22:04:01 -0500
Subject: [PATCH] Namco 163 refinements

---
 papers/format.md             |  9 +++++++++
 src/engine/engine.h          |  4 ++--
 src/engine/instrument.cpp    | 12 ++++++++++++
 src/engine/instrument.h      |  4 ++--
 src/engine/platform/n163.cpp |  2 +-
 src/gui/insEdit.cpp          | 11 ++++-------
 6 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/papers/format.md b/papers/format.md
index d61e94d43..dd4bcce2d 100644
--- a/papers/format.md
+++ b/papers/format.md
@@ -29,6 +29,7 @@ furthermore, an `or reserved` indicates this field is always present, but is res
 
 the format versions are:
 
+- 73: Furnace dev73
 - 72: Furnace dev72
 - 71: Furnace dev71
 - 70: Furnace dev70
@@ -515,6 +516,14 @@ size | description
      | - 480 bytes
  2?? | note sample × 120
      | - 240 bytes
+ --- | **Namco 163 data** (>=73)
+  4  | initial waveform
+  1  | wave position
+  1  | wave length
+  1  | wave mode:
+     | - bit 1: update on change
+     | - bit 0: load on playback
+  1  | reserved
 ```
 
 # wavetable
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 24c3e1352..0751941ee 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -42,8 +42,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev72"
-#define DIV_ENGINE_VERSION 72
+#define DIV_VERSION "dev73"
+#define DIV_ENGINE_VERSION 73
 
 // for imports
 #define DIV_VERSION_MOD 0xff01
diff --git a/src/engine/instrument.cpp b/src/engine/instrument.cpp
index 6556bfea9..f3cf9f591 100644
--- a/src/engine/instrument.cpp
+++ b/src/engine/instrument.cpp
@@ -387,6 +387,11 @@ void DivInstrument::putInsData(SafeWriter* w) {
   }
 
   // N163
+  w->writeI(n163.wave);
+  w->writeC(n163.wavePos);
+  w->writeC(n163.waveLen);
+  w->writeC(n163.waveMode);
+  w->writeC(0); // reserved
 }
 
 DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
@@ -743,6 +748,13 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
   }
 
   // N163
+  if (version>=73) {
+    n163.wave=reader.readI();
+    n163.wavePos=(unsigned char)reader.readC();
+    n163.waveLen=(unsigned char)reader.readC();
+    n163.waveMode=(unsigned char)reader.readC();
+    reader.readC(); // reserved
+  }
   return DIV_DATA_SUCCESS;
 }
 
diff --git a/src/engine/instrument.h b/src/engine/instrument.h
index a69800a1f..9d51670c1 100644
--- a/src/engine/instrument.h
+++ b/src/engine/instrument.h
@@ -392,8 +392,8 @@ struct DivInstrumentN163 {
   DivInstrumentN163():
     wave(-1),
     wavePos(0),
-    waveLen(0),
-    waveMode(0) {}
+    waveLen(32),
+    waveMode(3) {}
 };
 
 struct DivInstrument {
diff --git a/src/engine/platform/n163.cpp b/src/engine/platform/n163.cpp
index 42b55e907..14c2d12db 100644
--- a/src/engine/platform/n163.cpp
+++ b/src/engine/platform/n163.cpp
@@ -34,7 +34,7 @@
     rWriteMask(0x78-(c<<3)+(a&7),v,m) \
   }
 
-#define CHIP_FREQBASE (15*65536)
+#define CHIP_FREQBASE (15*32768)
 
 const char* regCheatSheetN163[]={
   "FreqL7", "40",
diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index da5b0e519..4d707f81f 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -2043,19 +2043,16 @@ void FurnaceGUI::drawInsEdit() {
           }
           ImGui::EndTabItem();
         }
-        if (ins->type==DIV_INS_N163) if (ImGui::BeginTabItem("N163")) {
-          ImGui::Text("Initial waveform");
-          if (ImGui::InputInt("##WAVE",&ins->n163.wave,1,10)) { PARAMETER
+        if (ins->type==DIV_INS_N163) if (ImGui::BeginTabItem("Namco 163")) {
+          if (ImGui::InputInt("Waveform##WAVE",&ins->n163.wave,1,10)) { PARAMETER
             if (ins->n163.wave<0) ins->n163.wave=0;
             if (ins->n163.wave>=e->song.waveLen) ins->n163.wave=e->song.waveLen-1;
           }
-          ImGui::Text("Initial waveform position in RAM");
-          if (ImGui::InputInt("##WAVEPOS",&ins->n163.wavePos,1,16)) { PARAMETER
+          if (ImGui::InputInt("Offset##WAVEPOS",&ins->n163.wavePos,1,16)) { PARAMETER
             if (ins->n163.wavePos<0) ins->n163.wavePos=0;
             if (ins->n163.wavePos>255) ins->n163.wavePos=255;
           }
-          ImGui::Text("Initial waveform length in RAM");
-          if (ImGui::InputInt("##WAVELEN",&ins->n163.waveLen,4,16)) { PARAMETER
+          if (ImGui::InputInt("Length##WAVELEN",&ins->n163.waveLen,4,16)) { PARAMETER
             if (ins->n163.waveLen<0) ins->n163.waveLen=0;
             if (ins->n163.waveLen>252) ins->n163.waveLen=252;
             ins->n163.waveLen&=0xfc;