NES: Calculate auto-mapper CRC32 over 8192 bytes instead of 512

This should fix about 70% of misidentified auto-mapper settings.

Author: sanni

Cart_Reader/Cart_Reader.ino

@@ -1297,6 +1297,11 @@ void mainMenu() {
       display_Clear();
       display_Update();
       setup_NES();
+      // Wait for MMC3
+      for (size_t c = 0; c < 512; c++) {
+        read_prg_byte(0x8000 + c);
+        read_prg_byte(0xE000 + c);
+      }
       getMapping();
       checkStatus_NES();
       return nesMenu();
@@ -3774,4 +3779,3 @@ void loop() {
 //******************************************
 // End of File
 //******************************************
-

Cart_Reader/NES.ino

@@ -796,9 +796,9 @@ void getMapping() {
     // never reached
   }
 
-  // Read first 512 bytes of first and last block of PRG ROM and compute CRC32
+  // Read last 8kb block of PRG ROM and compute CRC32
   // Some mappers (like MMC3) map the last 8KB block of PRG ROM to 0xE000 while 0x8000 can contain random data after bootup
-  for (size_t c = 0; c < 512; c++) {
+  for (size_t c = 0; c < 8192; c++) {
     UPDATE_CRC(oldcrc32, read_prg_byte(0x8000 + c));
     UPDATE_CRC(oldcrc32MMC3, read_prg_byte(0xE000 + c));
   }