# HG changeset patch
# User Michael Pavone <pavone@retrodev.com>
# Date 1592033932 25200
# Node ID 8ad431312aa7634ba01addfd1ab5f0f142b8e799
# Parent  7d4df6b74263b5eca80bdddfdaf00c555448cefa# Parent  0cbc456972c9b51e2c97624b0dd628b3c5dfeb51
Merge

diff -r 7d4df6b74263 -r 8ad431312aa7 genesis.c
--- a/genesis.c	Sat Jun 13 00:37:22 2020 -0700
+++ b/genesis.c	Sat Jun 13 00:38:52 2020 -0700
@@ -1089,7 +1089,7 @@
 {
 	m68k_context *context = vcontext;
 	genesis_context *gen = context->system;
-	if ((location >= 0xA13000 && location < 0xA13100) || (location >= 0xA12000 && location < 0xA12100)) {
+	if (location < 0x800000 || (location >= 0xA13000 && location < 0xA13100) || (location >= 0xA12000 && location < 0xA12100)) {
 		//Only called if the cart/exp doesn't have a more specific handler for this region
 		return get_open_bus_value(&gen->header);
 	} else if (location == 0xA14000 || location == 0xA14002) {
@@ -1131,7 +1131,9 @@
 		gen->tmss_lock[location >> 1 & 1] = value;
 	} else if (has_tmss && location == 0xA14100) {
 		//TODO: implement TMSS control register
-	} else if (location < 0xA12000 || location >= 0xA13100 || (location >= 0xA12100 && location < 0xA13000)) {
+	} else if (location < 0x800000 || (location >= 0xA13000 && location < 0xA13100) || (location >= 0xA12000 && location < 0xA12100)) {
+		//these writes are ignored when no relevant hardware is present
+	} else {
 		fatal_error("Machine freeze due to unmapped write to %X\n", location);
 	}
 	return vcontext;
@@ -1153,7 +1155,9 @@
 		}
 	} else if (has_tmss && (location == 0xA14100 || location == 0xA14101)) {
 		//TODO: implement TMSS control register
-	} else if (location < 0xA12000 || location >= 0xA13100 || (location >= 0xA12100 && location < 0xA13000)) {
+	} else if (location < 0x800000 || (location >= 0xA13000 && location < 0xA13100) || (location >= 0xA12000 && location < 0xA12100)) {
+		//these writes are ignored when no relevant hardware is present
+	} else {
 		fatal_error("Machine freeze due to unmapped byte write to %X\n", location);
 	}
 	return vcontext;
diff -r 7d4df6b74263 -r 8ad431312aa7 rom.db
--- a/rom.db	Sat Jun 13 00:37:22 2020 -0700
+++ b/rom.db	Sat Jun 13 00:38:52 2020 -0700
@@ -1377,3 +1377,17 @@
 		}
 	}
 }
+NETO-001 {
+	name Sonic Delta
+	map {
+		0 {
+			device ROM
+			last 7FFFF
+		}
+		80000 {
+			device Sega mapper
+			last 3FFFFF
+			offset 80000
+		}
+	}
+}