carthw: more accurate x-in-1 pirate handling

There is no A0 so it should be masked out. Even though the cart could
use use LWR as A0, it's not actually connected as seen here:
http://gendev.spritesmind.net/forum/viewtopic.php?f=2&p=37995

diff --git a/pico/carthw/carthw.c b/pico/carthw/carthw.c
index e00843d..58669f5 100644 (file)
--- a/pico/carthw/carthw.c
+++ b/pico/carthw/carthw.c
@@ -133,7 +133,7 @@ static carthw_state_chunk carthw_Xin1_state[] =
        { 0,            0,                         NULL }
 };
 
-// TODO: test a0, reads, w16
+// TODO: reads should also work, but then we need to handle open bus
 static void carthw_Xin1_write8(u32 a, u32 d)
 {
        if ((a & 0xffff00) != 0xa13000) {
@@ -141,12 +141,23 @@ static void carthw_Xin1_write8(u32 a, u32 d)
                return;
        }
 
-       carthw_Xin1_do(a, 0x3f, 16);
+       carthw_Xin1_do(a, 0x3e, 16);
+}
+
+static void carthw_Xin1_write16(u32 a, u32 d)
+{
+  if ((a & 0xffff00) != 0xa13000) {
+    PicoWrite16_io(a, d);
+    return;
+  }
+
+  carthw_Xin1_write8(a + 1, d);
 }
 
 static void carthw_Xin1_mem_setup(void)
 {
-       cpu68k_map_set(m68k_write8_map, 0xa10000, 0xa1ffff, carthw_Xin1_write8, 1);
+       cpu68k_map_set(m68k_write8_map,  0xa10000, 0xa1ffff, carthw_Xin1_write8, 1);
+       cpu68k_map_set(m68k_write16_map, 0xa10000, 0xa1ffff, carthw_Xin1_write16, 1);
 }
 
 static void carthw_Xin1_reset(void)