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 "CartF8.hxx" |
20 | |
21 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
22 | CartridgeF8::CartridgeF8(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 CartridgeF8::reset() |
34 | { |
35 | initializeStartBank(1); |
36 | |
37 | // Upon reset we switch to the reset bank |
38 | bank(startBank()); |
39 | } |
40 | |
41 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
42 | void CartridgeF8::install(System& system) |
43 | { |
44 | mySystem = &system; |
45 | |
46 | // Install pages for the startup bank |
47 | bank(startBank()); |
48 | } |
49 | |
50 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
51 | uInt8 CartridgeF8::peek(uInt16 address) |
52 | { |
53 | address &= 0x0FFF; |
54 | |
55 | // Switch banks if necessary |
56 | switch(address) |
57 | { |
58 | case 0x0FF8: |
59 | // Set the current bank to the lower 4k bank |
60 | bank(0); |
61 | break; |
62 | |
63 | case 0x0FF9: |
64 | // Set the current bank to the upper 4k bank |
65 | bank(1); |
66 | break; |
67 | |
68 | default: |
69 | break; |
70 | } |
71 | |
72 | return myImage[myBankOffset + address]; |
73 | } |
74 | |
75 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
76 | bool CartridgeF8::poke(uInt16 address, uInt8) |
77 | { |
78 | address &= 0x0FFF; |
79 | |
80 | // Switch banks if necessary |
81 | switch(address) |
82 | { |
83 | case 0x0FF8: |
84 | // Set the current bank to the lower 4k bank |
85 | bank(0); |
86 | break; |
87 | |
88 | case 0x0FF9: |
89 | // Set the current bank to the upper 4k bank |
90 | bank(1); |
91 | break; |
92 | |
93 | default: |
94 | break; |
95 | } |
96 | return false; |
97 | } |
98 | |
99 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
100 | bool CartridgeF8::bank(uInt16 bank) |
101 | { |
102 | if(bankLocked()) return false; |
103 | |
104 | // Remember what bank we're in |
105 | myBankOffset = bank << 12; |
106 | |
107 | System::PageAccess access(this, System::PageAccessType::READ); |
108 | |
109 | // Set the page accessing methods for the hot spots |
110 | for(uInt16 addr = (0x1FF8 & ~System::PAGE_MASK); addr < 0x2000; |
111 | addr += System::PAGE_SIZE) |
112 | { |
113 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
114 | mySystem->setPageAccess(addr, access); |
115 | } |
116 | |
117 | // Setup the page access methods for the current bank |
118 | for(uInt16 addr = 0x1000; addr < (0x1FF8U & ~System::PAGE_MASK); |
119 | addr += System::PAGE_SIZE) |
120 | { |
121 | access.directPeekBase = &myImage[myBankOffset + (addr & 0x0FFF)]; |
122 | access.codeAccessBase = &myCodeAccessBase[myBankOffset + (addr & 0x0FFF)]; |
123 | mySystem->setPageAccess(addr, access); |
124 | } |
125 | return myBankChanged = true; |
126 | } |
127 | |
128 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
129 | uInt16 CartridgeF8::getBank(uInt16) const |
130 | { |
131 | return myBankOffset >> 12; |
132 | } |
133 | |
134 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
135 | uInt16 CartridgeF8::bankCount() const |
136 | { |
137 | return 2; |
138 | } |
139 | |
140 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
141 | bool CartridgeF8::patch(uInt16 address, uInt8 value) |
142 | { |
143 | myImage[myBankOffset + (address & 0x0FFF)] = value; |
144 | return myBankChanged = true; |
145 | } |
146 | |
147 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
148 | const uInt8* CartridgeF8::getImage(size_t& size) const |
149 | { |
150 | size = myImage.size(); |
151 | return myImage.data(); |
152 | } |
153 | |
154 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
155 | bool CartridgeF8::save(Serializer& out) const |
156 | { |
157 | try |
158 | { |
159 | out.putShort(myBankOffset); |
160 | } |
161 | catch(...) |
162 | { |
163 | cerr << "ERROR: CartridgeF8::save" << endl; |
164 | return false; |
165 | } |
166 | |
167 | return true; |
168 | } |
169 | |
170 | // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
171 | bool CartridgeF8::load(Serializer& in) |
172 | { |
173 | try |
174 | { |
175 | myBankOffset = in.getShort(); |
176 | } |
177 | catch(...) |
178 | { |
179 | cerr << "ERROR: CartridgeF8::load" << endl; |
180 | return false; |
181 | } |
182 | |
183 | // Remember what bank we were in |
184 | bank(myBankOffset >> 12); |
185 | |
186 | return true; |
187 | } |
188 | |