1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Pacbox - a Pacman Emulator for Rockbox
*
* Based on PIE - Pacman Instructional Emulator
*
* Copyright (c) 1997-2003,2004 Alessandro Scotti
* http://www.ascotti.org/
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "plugin.h"
#include "hardware.h"
#include "wsg3.h"
/* The main data for Pacman */
unsigned char ram_[20*1024] IBSS_ATTR; // ROM (16K) and RAM (4K)
unsigned char charset_rom_[4*1024] IBSS_ATTR; // Character set ROM (4K)
unsigned char spriteset_rom_[4*1024] IBSS_ATTR; // Sprite set ROM (4K)
unsigned char dirty_[1024] IBSS_ATTR;
unsigned char video_mem_[1024] IBSS_ATTR; // Video memory (1K)
unsigned char color_mem_[1024] IBSS_ATTR; // Color memory (1K)
unsigned char charmap_[256*8*8] IBSS_ATTR; /* Character data for 256 8x8 characters */
unsigned char spritemap_[64*16*16]; /* Sprite data for 64 16x16 sprites */
unsigned char output_devices_ IBSS_ATTR; /* Output flip-flops set by the game program */
unsigned char interrupt_vector_ IBSS_ATTR;
unsigned coin_counter_ IBSS_ATTR;
unsigned char port1_ IBSS_ATTR;
unsigned char port2_ IBSS_ATTR;
unsigned char dip_switches_ IBSS_ATTR;
/* Internal tables and structures for faster access to data */
struct PacmanSprite sprites_[8]; /* Sprites */
short vchar_to_i_[1024];
/*
For Z80 Environment: write a byte to memory.
*/
void writeByte( unsigned addr, unsigned char b )
{
addr &= 0x7FFF;
if( addr < 0x4000 ) {
// This is a ROM address, do not write into it!
}
else if( addr < 0x4400 ) {
// Video memory
if (ram_[addr] != b) {
int x = vchar_to_i_[addr-0x4000];
ram_[addr] = b;
dirty_[x] = 1;
video_mem_[x] = b;
}
}
else if( addr < 0x4800 ) {
// Color memory
if (ram_[addr] != b) {
int x = vchar_to_i_[addr-0x4400];
ram_[addr] = b;
dirty_[x] = 1;
color_mem_[x] = b;
}
}
else if( addr < 0x4FF0 ) {
// Standard memory
ram_[addr] = b;
}
else if( addr < 0x5000 ) {
// Sprites
ram_[addr] = b;
unsigned idx = (addr - 0x4FF0) / 2;
if( addr & 1 ) {
sprites_[ idx ].color = b;
}
else {
sprites_[ idx ].n = b >> 2;
sprites_[ idx ].mode = b & 0x03;
}
}
else {
// Memory mapped ports
switch( addr ) {
case 0x5000:
// Interrupt enable
setOutputFlipFlop( InterruptEnabled, b & 0x01 );
break;
case 0x5001:
// Sound enable
setOutputFlipFlop( SoundEnabled, b & 0x01 );
break;
case 0x5002:
// Aux board enable?
break;
case 0x5003:
// Flip screen
setOutputFlipFlop( FlipScreen, b & 0x01 );
break;
case 0x5004:
// Player 1 start light
setOutputFlipFlop( PlayerOneLight, b & 0x01 );
break;
case 0x5005:
// Player 2 start light
setOutputFlipFlop( PlayerTwoLight, b & 0x01 );
break;
case 0x5006:
// Coin lockout: bit 0 is used to enable/disable the coin insert slots
// (0=disable).
// The coin slot is enabled at startup and (temporarily) disabled when
// the maximum number of credits (99) is inserted.
setOutputFlipFlop( CoinLockout, b & 0x01 );
break;
case 0x5007:
// Coin meter (coin counter incremented on 0/1 edge)
if( (output_devices_ & CoinMeter) == 0 && (b & 0x01) != 0 )
coin_counter_++;
setOutputFlipFlop( CoinMeter, b & 0x01 );
break;
case 0x50c0:
// Watchdog reset
break;
default:
if( addr >= 0x5040 && addr < 0x5060 ) {
// Sound registers
wsg3_set_register( addr-0x5040, b );
}
else if( addr >= 0x5060 && addr < 0x5070 ) {
// Sprite coordinates, x/y pairs for 8 sprites
unsigned idx = (addr-0x5060) / 2;
if( addr & 1 ) {
sprites_[ idx ].y = 272 - b + 1;
}
else {
sprites_[ idx ].x = 240 - b - 1;
if( idx <= 2 ) {
// In Pacman the first few sprites must be further offset
// to the left to get a correct display (is this a hack?)
sprites_[ idx ].x -= 1;
}
}
}
break;
}
}
}
/*
For Z80 Environment: read from a port.
Note: all ports in Pacman are memory mapped so they are read with readByte().
*/
unsigned char readPort( unsigned port )
{
(void)port;
return 0;
}
/*
For Z80 Environment: write to a port.
*/
void writePort( unsigned addr, unsigned char b )
{
if( addr == 0 ) {
// Sets the interrupt vector for the next CPU interrupt
interrupt_vector_ = b;
}
}
void setOutputFlipFlop( unsigned char bit, unsigned char value )
{
if( value ) {
output_devices_ |= bit;
}
else {
output_devices_ &= ~bit;
}
}
|
