X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=pico%2Fz80if.c;h=cb0fa9b11b9f7317022082c64b72ad1367c30446;hb=bc3aea8e705ec38bdeca7f31fa069c37dd7217d3;hp=10c438abce2dda097f2c213cb1a9b085be8b4ea1;hpb=b4db550e41b2aa277f570d7bff890c8e8ee1831f;p=picodrive.git

diff --git a/pico/z80if.c b/pico/z80if.c
index 10c438a..cb0fa9b 100644
--- a/pico/z80if.c
+++ b/pico/z80if.c
@@ -1,3 +1,11 @@
+/*
+ * PicoDrive
+ * (C) notaz, 2007-2010
+ *
+ * This work is licensed under the terms of MAME license.
+ * See COPYING file in the top-level directory.
+ */
+
 #include <stddef.h>
 #include "pico_int.h"
 #include "memory.h"
@@ -71,25 +79,28 @@ void z80_init(void)
 void z80_reset(void)
 {
 #ifdef _USE_DRZ80
-  memset(&drZ80, 0, 0x54);
+  drZ80.Z80I = 0;
+  drZ80.Z80IM = 0;
+  drZ80.Z80IF = 0;
+  drZ80.z80irqvector = 0xff0000; // RST 38h
+  drZ80.Z80PC_BASE = drZ80.Z80PC = z80_read_map[0] << 1;
+  // others not changed, undefined on cold boot
+/*
   drZ80.Z80F  = (1<<2);  // set ZFlag
   drZ80.Z80F2 = (1<<2);  // set ZFlag
   drZ80.Z80IX = 0xFFFF << 16;
   drZ80.Z80IY = 0xFFFF << 16;
-  drZ80.Z80I = 0;
-  drZ80.Z80IM = 0; // 1?
-  drZ80.z80irqvector = 0xff0000; // RST 38h
-  drZ80.Z80PC_BASE = drZ80.Z80PC = z80_read_map[0] << 1;
+*/
   // drZ80 is locked in single bank
   drz80_sp_base = (PicoAHW & PAHW_SMS) ? 0xc000 : 0x0000;
   drZ80.Z80SP_BASE = z80_read_map[drz80_sp_base >> Z80_MEM_SHIFT] << 1;
   if (PicoAHW & PAHW_SMS)
     drZ80.Z80SP = drZ80.Z80SP_BASE + 0xdff0; // simulate BIOS
+  // XXX: since we use direct SP pointer, it might make sense to force it to RAM,
+  // but we'll rely on built-in stack protection for now
 #endif
 #ifdef _USE_CZ80
   Cz80_Reset(&CZ80);
-  Cz80_Set_Reg(&CZ80, CZ80_IX, 0xffff);
-  Cz80_Set_Reg(&CZ80, CZ80_IY, 0xffff);
   if (PicoAHW & PAHW_SMS)
     Cz80_Set_Reg(&CZ80, CZ80_SP, 0xdff0);
 #endif