1 | //============================================================================ |
2 | // |
3 | // SSSS tt lll lll |
4 | // SS SS tt ll ll |
5 | // SS tttttt eeee ll ll aaaa |
6 | // SSSS tt ee ee ll ll aa |
7 | // SS tt eeeeee ll ll aaaaa -- "An Atari 2600 VCS Emulator" |
8 | // SS SS tt ee ll ll aa aa |
9 | // SSSS ttt eeeee llll llll aaaaa |
10 | // |
11 | // Copyright (c) 1995-2019 by Bradford W. Mott, Stephen Anthony |
12 | // and the Stella Team |
13 | // |
14 | // See the file "License.txt" for information on usage and redistribution of |
15 | // this file, and for a DISCLAIMER OF ALL WARRANTIES. |
16 | //============================================================================ |
17 | |
18 | #include "System.hxx" |
19 | #include "M6532.hxx" |
20 | #include "TIA.hxx" |
21 | #include "CartX07.hxx" |
22 | |
23 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
24 | CartridgeX07::CartridgeX07(const ByteBuffer& image, size_t size, |
25 | const string& md5, const Settings& settings) |
26 | : Cartridge(settings, md5), |
27 | myCurrentBank(0) |
28 | { |
29 | // Copy the ROM image into my buffer |
30 | std::copy_n(image.get(), std::min(myImage.size(), size), myImage.begin()); |
31 | createCodeAccessBase(myImage.size()); |
32 | } |
33 | |
34 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
35 | void CartridgeX07::reset() |
36 | { |
37 | // Upon reset we switch to the startup bank |
38 | initializeStartBank(0); |
39 | bank(startBank()); |
40 | } |
41 | |
42 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
43 | void CartridgeX07::install(System& system) |
44 | { |
45 | mySystem = &system; |
46 | |
47 | // Set the page accessing methods for the hot spots |
48 | // The hotspots use almost all addresses below 0x1000, so we simply grab them |
49 | // all and forward the TIA/RIOT calls from the peek and poke methods. |
50 | System::PageAccess access(this, System::PageAccessType::READWRITE); |
51 | for(uInt16 addr = 0x00; addr < 0x1000; addr += System::PAGE_SIZE) |
52 | mySystem->setPageAccess(addr, access); |
53 | |
54 | // Install pages for the startup bank |
55 | bank(startBank()); |
56 | } |
57 | |
58 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
59 | uInt8 CartridgeX07::peek(uInt16 address) |
60 | { |
61 | uInt8 value = 0; |
62 | |
63 | // Check for RAM or TIA mirroring |
64 | uInt16 lowAddress = address & 0x3ff; |
65 | if(lowAddress & 0x80) |
66 | value = mySystem->m6532().peek(address); |
67 | else if(!(lowAddress & 0x200)) |
68 | value = mySystem->tia().peek(address); |
69 | |
70 | // Switch banks if necessary |
71 | if((address & 0x180f) == 0x080d) |
72 | bank((address & 0xf0) >> 4); |
73 | else if((address & 0x1880) == 0) |
74 | { |
75 | if((myCurrentBank & 0xe) == 0xe) |
76 | bank(((address & 0x40) >> 6) | (myCurrentBank & 0xe)); |
77 | } |
78 | |
79 | return value; |
80 | } |
81 | |
82 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
83 | bool CartridgeX07::poke(uInt16 address, uInt8 value) |
84 | { |
85 | // Check for RAM or TIA mirroring |
86 | uInt16 lowAddress = address & 0x3ff; |
87 | if(lowAddress & 0x80) |
88 | mySystem->m6532().poke(address, value); |
89 | else if(!(lowAddress & 0x200)) |
90 | mySystem->tia().poke(address, value); |
91 | |
92 | // Switch banks if necessary |
93 | if((address & 0x180f) == 0x080d) |
94 | bank((address & 0xf0) >> 4); |
95 | else if((address & 0x1880) == 0) |
96 | { |
97 | if((myCurrentBank & 0xe) == 0xe) |
98 | bank(((address & 0x40) >> 6) | (myCurrentBank & 0xe)); |
99 | } |
100 | return false; |
101 | } |
102 | |
103 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
104 | bool CartridgeX07::bank(uInt16 bank) |
105 | { |
106 | if(bankLocked()) return false; |
107 | |
108 | // Remember what bank we're in |
109 | myCurrentBank = (bank & 0x0f); |
110 | uInt32 offset = myCurrentBank << 12; |
111 | |
112 | // Setup the page access methods for the current bank |
113 | System::PageAccess access(this, System::PageAccessType::READ); |
114 | |
115 | // Map ROM image into the system |
116 | for(uInt16 addr = 0x1000; addr < 0x2000; addr += System::PAGE_SIZE) |
117 | { |
118 | access.directPeekBase = &myImage[offset + (addr & 0x0FFF)]; |
119 | access.codeAccessBase = &myCodeAccessBase[offset + (addr & 0x0FFF)]; |
120 | mySystem->setPageAccess(addr, access); |
121 | } |
122 | return myBankChanged = true; |
123 | } |
124 | |
125 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
126 | uInt16 CartridgeX07::getBank(uInt16) const |
127 | { |
128 | return myCurrentBank; |
129 | } |
130 | |
131 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
132 | uInt16 CartridgeX07::bankCount() const |
133 | { |
134 | return 16; |
135 | } |
136 | |
137 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
138 | bool CartridgeX07::patch(uInt16 address, uInt8 value) |
139 | { |
140 | myImage[(myCurrentBank << 12) + (address & 0x0FFF)] = value; |
141 | return myBankChanged = true; |
142 | } |
143 | |
144 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
145 | const uInt8* CartridgeX07::getImage(size_t& size) const |
146 | { |
147 | size = myImage.size(); |
148 | return myImage.data(); |
149 | } |
150 | |
151 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
152 | bool CartridgeX07::save(Serializer& out) const |
153 | { |
154 | try |
155 | { |
156 | out.putShort(myCurrentBank); |
157 | } |
158 | catch(...) |
159 | { |
160 | cerr << "ERROR: CartridgeX07::save" << endl; |
161 | return false; |
162 | } |
163 | |
164 | return true; |
165 | } |
166 | |
167 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
168 | bool CartridgeX07::load(Serializer& in) |
169 | { |
170 | try |
171 | { |
172 | myCurrentBank = in.getShort(); |
173 | } |
174 | catch(...) |
175 | { |
176 | cerr << "ERROR: CartridgeX07::load" << endl; |
177 | return false; |
178 | } |
179 | |
180 | // Remember what bank we were in |
181 | bank(myCurrentBank); |
182 | |
183 | return true; |
184 | } |
185 | |