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-rw-r--r--src/mame/drivers/alinvade.c14
1 files changed, 7 insertions, 7 deletions
diff --git a/src/mame/drivers/alinvade.c b/src/mame/drivers/alinvade.c
index bbbefd61466..7f7a987487c 100644
--- a/src/mame/drivers/alinvade.c
+++ b/src/mame/drivers/alinvade.c
@@ -1,20 +1,20 @@
/*
tiny bartop b&w Space Invaders type game with colour overlay
-
+
Driver by David Haywood and Mariusz Wojcieszek
TODO:
- 16 bytes are protected in the c*** range. I'm guessing they used a PROM to protect a
simple sub-routine because:
- * It attempts to jsr from RAM to that area with a 0x10 byte offset (i.e. ROM copies a code snippet to RAM; when it executes
+ * It attempts to jsr from RAM to that area with a 0x10 byte offset (i.e. ROM copies a code snippet to RAM; when it executes
it code executes jsr 0xc400 then self-modifies it to 0xc410, rinse and repeat ... up to 0xc7f0 and rolls back);
- * After that the program has an amusing left-over located at 0xe000-0xe00f (yup, NOPs + a RTS), with the
+ * After that the program has an amusing left-over located at 0xe000-0xe00f (yup, NOPs + a RTS), with the
exact same number of times as above;
It's unknown at current stage what it really protects tho, game seems working for all I can see ... -AS
- Sound is entirely guesswork.
-
+
*/
#include "emu.h"
@@ -28,10 +28,10 @@ public:
alinvade_state(const machine_config &mconfig, device_type type, const char *tag)
: driver_device(mconfig, type, tag)
, m_maincpu(*this, "maincpu")
- , m_videoram(*this, "videoram")
+ , m_videoram(*this, "videoram")
, m_discrete(*this, "discrete")
{ }
-
+
DECLARE_READ8_MEMBER(irqmask_r);
DECLARE_WRITE8_MEMBER(irqmask_w);
DECLARE_WRITE8_MEMBER(sound_w);
@@ -90,7 +90,7 @@ WRITE8_MEMBER(alinvade_state::irqmask_w)
{
if((!(irqff & 1)) && (data & 1)) // f/f, active high? If the above actually returns 0xff this could be active low ...
irqmask^= 1;
-
+
irqff = data;
}