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 "CartF0.hxx" |
20 | |
21 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
22 | CartridgeF0::CartridgeF0(const ByteBuffer& image, size_t size, |
23 | const string& md5, const Settings& settings) |
24 | : Cartridge(settings, md5), |
25 | myBankOffset(0) |
26 | { |
27 | // Copy the ROM image into my buffer |
28 | std::copy_n(image.get(), std::min(myImage.size(), size), myImage.begin()); |
29 | createCodeAccessBase(myImage.size()); |
30 | } |
31 | |
32 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
33 | void CartridgeF0::reset() |
34 | { |
35 | // Upon reset we switch to the startup bank |
36 | initializeStartBank(15); |
37 | bank(startBank()); |
38 | } |
39 | |
40 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
41 | void CartridgeF0::install(System& system) |
42 | { |
43 | mySystem = &system; |
44 | |
45 | // Install pages for the startup bank |
46 | bank(startBank()); |
47 | } |
48 | |
49 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
50 | uInt8 CartridgeF0::peek(uInt16 address) |
51 | { |
52 | address &= 0x0FFF; |
53 | |
54 | // Switch to next bank |
55 | if(address == 0x0FF0) |
56 | incbank(); |
57 | |
58 | return myImage[myBankOffset + address]; |
59 | } |
60 | |
61 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
62 | bool CartridgeF0::poke(uInt16 address, uInt8) |
63 | { |
64 | address &= 0x0FFF; |
65 | |
66 | // Switch to next bank |
67 | if(address == 0x0FF0) |
68 | incbank(); |
69 | |
70 | return false; |
71 | } |
72 | |
73 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
74 | void CartridgeF0::incbank() |
75 | { |
76 | // Determine current bank, and increment to the next one |
77 | uInt8 nextBank = ((myBankOffset >> 12) + 1) & 0x0F; |
78 | bank(nextBank); |
79 | } |
80 | |
81 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
82 | bool CartridgeF0::bank(uInt16 bank) |
83 | { |
84 | if(bankLocked()) return false; |
85 | |
86 | // Remember what bank we're in |
87 | myBankOffset = bank << 12; |
88 | |
89 | System::PageAccess access(this, System::PageAccessType::READ); |
90 | |
91 | // Set the page accessing methods for the hot spots |
92 | for(uInt16 addr = (0x1FF0 & ~System::PAGE_MASK); addr < 0x2000; |
93 | addr += System::PAGE_SIZE) |
94 | { |
95 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
96 | mySystem->setPageAccess(addr, access); |
97 | } |
98 | |
99 | // Setup the page access methods for the current bank |
100 | for(uInt16 addr = 0x1000; addr < (0x1FF0U & ~System::PAGE_MASK); |
101 | addr += System::PAGE_SIZE) |
102 | { |
103 | access.directPeekBase = &myImage[myBankOffset + (addr & 0x0FFF)]; |
104 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
105 | mySystem->setPageAccess(addr, access); |
106 | } |
107 | |
108 | return myBankChanged = true; |
109 | } |
110 | |
111 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
112 | uInt16 CartridgeF0::getBank(uInt16) const |
113 | { |
114 | return myBankOffset >> 12; |
115 | } |
116 | |
117 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
118 | uInt16 CartridgeF0::bankCount() const |
119 | { |
120 | return 16; |
121 | } |
122 | |
123 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
124 | bool CartridgeF0::patch(uInt16 address, uInt8 value) |
125 | { |
126 | myImage[myBankOffset + (address & 0x0FFF)] = value; |
127 | return myBankChanged = true; |
128 | } |
129 | |
130 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
131 | const uInt8* CartridgeF0::getImage(size_t& size) const |
132 | { |
133 | size = myImage.size(); |
134 | return myImage.data(); |
135 | } |
136 | |
137 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
138 | bool CartridgeF0::save(Serializer& out) const |
139 | { |
140 | try |
141 | { |
142 | out.putShort(myBankOffset); |
143 | } |
144 | catch(...) |
145 | { |
146 | cerr << "ERROR: CartridgeF0::save" << endl; |
147 | return false; |
148 | } |
149 | |
150 | return true; |
151 | } |
152 | |
153 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
154 | bool CartridgeF0::load(Serializer& in) |
155 | { |
156 | try |
157 | { |
158 | myBankOffset = in.getShort(); |
159 | } |
160 | catch(...) |
161 | { |
162 | cerr << "ERROR: CartridgeF0::load" << endl; |
163 | return false; |
164 | } |
165 | |
166 | // Remember what bank we were in |
167 | bank(myBankOffset >> 12); |
168 | |
169 | return true; |
170 | } |
171 | |