From 5f8081603357891b082b4719eb032a9422c8dee9 Mon Sep 17 00:00:00 2001 From: Bryan McPhail Date: Tue, 5 Jan 2010 22:50:03 +0000 Subject: [PATCH] fix zeroize protection simulation in lieu of proper dongle dump. --- src/mame/machine/decocass.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/mame/machine/decocass.c b/src/mame/machine/decocass.c index faa038887c1..506f952c69e 100644 --- a/src/mame/machine/decocass.c +++ b/src/mame/machine/decocass.c @@ -1679,12 +1679,15 @@ MACHINE_RESET( czeroize ) /* * FIXME: remove if the original ROM is available. * The Zeroize 6502 code at 0x3707 issues LODCTRS with 0x8a, - * and expects to read 0x18 from 0x08a0 ff. within 7 bytes. + * and expects to read 0x18 from 0x08a0 ff. within 7 bytes + * and 0xf7 from 0x8a1 (which 0xd is subtracted from presumably in order + * to form a NOP of 0xea). * This hack seems to be sufficient to get around * the missing dongle ROM contents and play the game. */ memset(mem, 0x00, 0x1000); mem[0x08a0] = 0x18; + mem[0x08a1] = 0xf7; } /***************************************************************************