From 36c01f4c8db39640523cdfa9d3ab273161cd5b1e Mon Sep 17 00:00:00 2001
From: splash5 <2173030+splash5@users.noreply.github.com>
Date: Wed, 14 Dec 2022 11:47:53 +0800
Subject: [PATCH] Add NES mapper 209

Tested with "Shin Samurai Spirits 2 (JY-083)"
---
 Cart_Reader/NES.ino | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/Cart_Reader/NES.ino b/Cart_Reader/NES.ino
index c7e2b01..de8a802 100644
--- a/Cart_Reader/NES.ino
+++ b/Cart_Reader/NES.ino
@@ -130,6 +130,7 @@ static const byte PROGMEM mapsize[] = {
   203, 1, 4, 1, 4, 0, 0,  // various NROM-128 multicarts [UNLICENSED]
   206, 1, 3, 2, 4, 0, 0,  // dxrom
   207, 4, 4, 5, 5, 0, 0,  // taito x1-005 variant (fudou myouou den)
+  209, 0, 7, 1, 8, 0, 0,  // J.Y. Company ASIC [UNLICENSED]
   210, 3, 5, 5, 6, 0, 0,  // namco 175/340
   212, 0, 3, 0, 4, 0, 0,  // BMC Super HiK 300-in-1 [UNLICENSED]
   213, 1, 6, 1, 6, 0, 0,  // BMC-GKB (C)NROM-based multicarts, duplicate of mapper 58 [UNLICENSED]
@@ -3380,6 +3381,19 @@ void readPRG(boolean readrom) {
         }
         break;
 
+      case 209:
+        banks = int_pow(2, prgsize) * 2;
+        write_prg_byte(0xD000, 0x02);
+
+        for (byte i = 0; i < banks; i++) {
+          write_prg_byte(0xD003, (((i >> 5) & 0x06) | 0x20));
+          write_prg_byte(0x8000, (i & 0x3f));
+          for (word address = 0x0; address < 0x2000; address += 512) {
+            dumpPRG(base, address);
+          }
+        }
+        break;
+
       case 210:  // 128K/256K
         banks = int_pow(2, prgsize) * 2;
         for (int i = 0; i < banks; i += 2) {
@@ -4353,6 +4367,19 @@ void readCHR(boolean readrom) {
           }
           break;
 
+        case 209:
+          banks = int_pow(2, chrsize) / 2;
+          write_prg_byte(0xD000, 0x02);
+
+          for (int i = 0; i < banks; i++) {
+            write_prg_byte(0xD003, (((i >> 3) & 0x18) | 0x20));
+            write_prg_byte(0x9000, (i & 0x3f));
+            for (word address = 0x0; address < 0x2000; address += 512) {
+              dumpCHR(address);
+            }
+          }
+          break;
+
         case 210:  // 128K/256K
           banks = int_pow(2, chrsize) * 4;
           write_prg_byte(0xE800, 0xC0);  // CHR RAM DISABLE (Bit 6 and 7) [WRITE NO RAM]