1 // $package. http://www.slack.net/~ant/
2
3 #include "Nes_Cpu.h"
4
5 #include "blargg_endian.h"
6
7 /* Copyright (C) 2003-2008 Shay Green. This module is free software; you
8 can redistribute it and/or modify it under the terms of the GNU Lesser
9 General Public License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version. This
11 module is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
14 details. You should have received a copy of the GNU Lesser General Public
15 License along with this module; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
17
18 #include "blargg_source.h"
19
set_code_page(int i,void const * p)20 inline void Nes_Cpu::set_code_page( int i, void const* p )
21 {
22 byte const* p2 = STATIC_CAST(byte const*,p) - NES_CPU_OFFSET( i * page_size );
23 cpu_state->code_map [i] = p2;
24 cpu_state_.code_map [i] = p2;
25 }
26
map_code(addr_t start,int size,void const * data,int mirror_size)27 void Nes_Cpu::map_code( addr_t start, int size, void const* data, int mirror_size )
28 {
29 // address range must begin and end on page boundaries
30 require( start % page_size == 0 );
31 require( size % page_size == 0 );
32 require( start + size <= 0x10000 );
33 require( mirror_size % page_size == 0 );
34
35 for ( int offset = 0; offset < size; offset += page_size )
36 set_code_page( NES_CPU_PAGE( start + offset ),
37 STATIC_CAST(char const*,data) + (offset & ((unsigned) mirror_size - 1)) );
38 }
39
reset(void const * unmapped_page)40 void Nes_Cpu::reset( void const* unmapped_page )
41 {
42 check( cpu_state == &cpu_state_ );
43 cpu_state = &cpu_state_;
44
45 r.flags = irq_inhibit_mask;
46 r.sp = 0xFF;
47 r.pc = 0;
48 r.a = 0;
49 r.x = 0;
50 r.y = 0;
51
52 cpu_state_.time = 0;
53 cpu_state_.base = 0;
54 irq_time_ = future_time;
55 end_time_ = future_time;
56 error_count_ = 0;
57
58 set_code_page( page_count, unmapped_page );
59 map_code( 0, 0x10000, unmapped_page, page_size );
60
61 blargg_verify_byte_order();
62 }
63