summaryrefslogtreecommitdiffstatshomepage
path: root/src/mame/machine/sms.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/mame/machine/sms.cpp')
-rw-r--r--src/mame/machine/sms.cpp6
1 files changed, 6 insertions, 0 deletions
diff --git a/src/mame/machine/sms.cpp b/src/mame/machine/sms.cpp
index 6f433f7145e..359422796dd 100644
--- a/src/mame/machine/sms.cpp
+++ b/src/mame/machine/sms.cpp
@@ -2,6 +2,7 @@
// copyright-holders:Wilbert Pol, Charles MacDonald,Mathis Rosenhauer,Brad Oliver,Michael Luong,Fabio Priuli,Enik Land
#include "emu.h"
#include "crsshair.h"
+#include "cpu/z80/z80.h"
#include "video/315_5124.h"
#include "sound/ym2413.h"
#include "includes/sms.h"
@@ -1081,6 +1082,11 @@ void sms_state::machine_start()
if (m_is_gamegear)
{
save_item(NAME(m_gg_sio));
+ // The game Ecco requires SP to be initialized, so, to run on a BIOS-less Game
+ // Gear, probably a custom chip like the 315-5378 does the initialization, as
+ // done by the 315-5342 chip on the Power Base Converter for Sega Genesis/MD.
+ // Reference: http://www.smspower.org/forums/14084-PowerBaseConverterInfo
+ m_maincpu->set_state_int(Z80_SP, 0xdff0);
}
if (m_cartslot)