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 "CartBF.hxx" |
20 | |
21 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
22 | CartridgeBF::CartridgeBF(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 CartridgeBF::reset() |
34 | { |
35 | initializeStartBank(1); |
36 | |
37 | // Upon reset we switch to the startup bank |
38 | bank(startBank()); |
39 | } |
40 | |
41 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
42 | void CartridgeBF::install(System& system) |
43 | { |
44 | mySystem = &system; |
45 | |
46 | // Install pages for the startup bank |
47 | bank(startBank()); |
48 | } |
49 | |
50 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
51 | uInt8 CartridgeBF::peek(uInt16 address) |
52 | { |
53 | // Due to the way addressing is set up, we will only get here if the |
54 | // address is in the hotspot range ($1F80 - $1FFF) |
55 | address &= 0x0FFF; |
56 | |
57 | // Switch banks if necessary |
58 | if((address >= 0x0F80) && (address <= 0x0FBF)) |
59 | bank(address - 0x0F80); |
60 | |
61 | return myImage[myBankOffset + address]; |
62 | } |
63 | |
64 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
65 | bool CartridgeBF::poke(uInt16 address, uInt8) |
66 | { |
67 | // Due to the way addressing is set up, we will only get here if the |
68 | // address is in the hotspot range ($1F80 - $1FFF) |
69 | address &= 0x0FFF; |
70 | |
71 | // Switch banks if necessary |
72 | if((address >= 0x0F80) && (address <= 0x0FBF)) |
73 | bank(address - 0x0F80); |
74 | |
75 | return false; |
76 | } |
77 | |
78 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
79 | bool CartridgeBF::bank(uInt16 bank) |
80 | { |
81 | if(bankLocked()) return false; |
82 | |
83 | // Remember what bank we're in |
84 | myBankOffset = bank << 12; |
85 | |
86 | System::PageAccess access(this, System::PageAccessType::READ); |
87 | |
88 | // Set the page accessing methods for the hot spots |
89 | for(uInt16 addr = (0x1F80 & ~System::PAGE_MASK); addr < 0x2000; |
90 | addr += System::PAGE_SIZE) |
91 | { |
92 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
93 | mySystem->setPageAccess(addr, access); |
94 | } |
95 | |
96 | // Setup the page access methods for the current bank |
97 | for(uInt16 addr = 0x1000; addr < (0x1F80U & ~System::PAGE_MASK); |
98 | addr += System::PAGE_SIZE) |
99 | { |
100 | access.directPeekBase = &myImage[myBankOffset + (addr & 0x0FFF)]; |
101 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
102 | mySystem->setPageAccess(addr, access); |
103 | } |
104 | return myBankChanged = true; |
105 | } |
106 | |
107 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
108 | uInt16 CartridgeBF::getBank(uInt16) const |
109 | { |
110 | return myBankOffset >> 12; |
111 | } |
112 | |
113 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
114 | uInt16 CartridgeBF::bankCount() const |
115 | { |
116 | return 64; |
117 | } |
118 | |
119 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
120 | bool CartridgeBF::patch(uInt16 address, uInt8 value) |
121 | { |
122 | myImage[myBankOffset + (address & 0x0FFF)] = value; |
123 | return myBankChanged = true; |
124 | } |
125 | |
126 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
127 | const uInt8* CartridgeBF::getImage(size_t& size) const |
128 | { |
129 | size = myImage.size(); |
130 | return myImage.data(); |
131 | } |
132 | |
133 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
134 | bool CartridgeBF::save(Serializer& out) const |
135 | { |
136 | try |
137 | { |
138 | out.putInt(myBankOffset); |
139 | } |
140 | catch(...) |
141 | { |
142 | cerr << "ERROR: CartridgeBF::save" << endl; |
143 | return false; |
144 | } |
145 | |
146 | return true; |
147 | } |
148 | |
149 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
150 | bool CartridgeBF::load(Serializer& in) |
151 | { |
152 | try |
153 | { |
154 | myBankOffset = in.getInt(); |
155 | } |
156 | catch(...) |
157 | { |
158 | cerr << "ERROR: CartridgeBF::load" << endl; |
159 | return false; |
160 | } |
161 | |
162 | // Remember what bank we were in |
163 | bank(myBankOffset >> 12); |
164 | |
165 | return true; |
166 | } |
167 | |