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authorSean Bartell <wingedtachikoma@gmail.com>2011-06-25 21:32:25 -0400
committerNils Wallménius <nils@rockbox.org>2012-04-25 22:13:20 +0200
commitf40bfc9267b13b54e6379dfe7539447662879d24 (patch)
tree9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libgme/nes_cpu.c
parenta0009907de7a0107d49040d8a180f140e2eff299 (diff)
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Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97 Reviewed-on: http://gerrit.rockbox.org/137 Reviewed-by: Nils Wallménius <nils@rockbox.org> Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libgme/nes_cpu.c')
-rw-r--r--lib/rbcodec/codecs/libgme/nes_cpu.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libgme/nes_cpu.c b/lib/rbcodec/codecs/libgme/nes_cpu.c
new file mode 100644
index 0000000..2092591
--- /dev/null
+++ b/lib/rbcodec/codecs/libgme/nes_cpu.c
@@ -0,0 +1,62 @@
+// Game_Music_Emu 0.6-pre. 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"
+
+static inline void set_code_page( struct Nes_Cpu* this, int i, void const* p )
+{
+ byte const* p2 = STATIC_CAST(byte const*,p) - NES_CPU_OFFSET( i * page_size );
+ this->cpu_state->code_map [i] = p2;
+ this->cpu_state_.code_map [i] = p2;
+}
+
+void Cpu_map_code( struct Nes_Cpu* this, 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 );
+
+ int offset;
+ for ( offset = 0; offset < size; offset += page_size )
+ set_code_page( this, NES_CPU_PAGE( start + offset ),
+ STATIC_CAST(char const*,data) + (offset & ((unsigned) mirror_size - 1)) );
+}
+
+void Cpu_reset( struct Nes_Cpu* this, void const* unmapped_page )
+{
+ check( this->cpu_state == &this->cpu_state_ );
+ this->cpu_state = &this->cpu_state_;
+
+ this->r.flags = irq_inhibit_mask;
+ this->r.sp = 0xFF;
+ this->r.pc = 0;
+ this->r.a = 0;
+ this->r.x = 0;
+ this->r.y = 0;
+
+ this->cpu_state_.time = 0;
+ this->cpu_state_.base = 0;
+ this->irq_time = future_time;
+ this->end_time = future_time;
+
+ set_code_page( this, page_count, unmapped_page );
+ Cpu_map_code( this, 0, 0x10000, unmapped_page, page_size );
+
+ blargg_verify_byte_order();
+}