cog/Frameworks/GME/gme/Nes_Cpu.cpp

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// $package. http://www.slack.net/~ant/
#include "Nes_Cpu.h"
#include "blargg_endian.h"
/* Copyright (C) 2003-2008 Shay Green. This module is free software; you
can redistribute it and/or modify it under the terms of the GNU Lesser
General Public License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version. This
module is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
details. You should have received a copy of the GNU Lesser General Public
License along with this module; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
#include "blargg_source.h"
inline void Nes_Cpu::set_code_page( int i, void const* p )
{
byte const* p2 = STATIC_CAST(byte const*,p) - NES_CPU_OFFSET( i * page_size );
cpu_state->code_map [i] = p2;
cpu_state_.code_map [i] = p2;
}
void Nes_Cpu::map_code( addr_t start, int size, void const* data, int mirror_size )
{
// address range must begin and end on page boundaries
require( start % page_size == 0 );
require( size % page_size == 0 );
require( start + size <= 0x10000 );
require( mirror_size % page_size == 0 );
for ( int offset = 0; offset < size; offset += page_size )
set_code_page( NES_CPU_PAGE( start + offset ),
STATIC_CAST(char const*,data) + (offset & ((unsigned) mirror_size - 1)) );
}
void Nes_Cpu::reset( void const* unmapped_page )
{
check( cpu_state == &cpu_state_ );
cpu_state = &cpu_state_;
r.flags = irq_inhibit_mask;
r.sp = 0xFF;
r.pc = 0;
r.a = 0;
r.x = 0;
r.y = 0;
cpu_state_.time = 0;
cpu_state_.base = 0;
irq_time_ = future_time;
end_time_ = future_time;
error_count_ = 0;
set_code_page( page_count, unmapped_page );
map_code( 0, 0x10000, unmapped_page, page_size );
blargg_verify_byte_order();
}