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comparison backend.c @ 1838:0c1491818f4b

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WIP new 68K core using CPU DSL
author Michael Pavone <pavone@retrodev.com>
date Thu, 18 Apr 2019 19:47:50 -0700
parents 33ec5df77fac
children 374a5ae694e8 42c12d141f6e
comparison
equal deleted inserted replaced
1837:f6ee0df6bb48 1838:0c1491818f4b
152 return chunk->read_16(offset, context); 152 return chunk->read_16(offset, context);
153 } 153 }
154 return 0xFFFF; 154 return 0xFFFF;
155 } 155 }
156 156
157 void write_word(uint32_t address, uint16_t value, void **mem_pointers, cpu_options *opts, void *context)
158 {
159 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL);
160 if (!chunk) {
161 return;
162 }
163 uint32_t offset = (address - chunk->start) & chunk->mask;
164 if (chunk->flags & MMAP_WRITE) {
165 uint8_t *base;
166 if (chunk->flags & MMAP_PTR_IDX) {
167 base = mem_pointers[chunk->ptr_index];
168 } else {
169 base = chunk->buffer;
170 }
171 if (base) {
172 if ((chunk->flags & MMAP_ONLY_ODD) || (chunk->flags & MMAP_ONLY_EVEN)) {
173 offset /= 2;
174 if (chunk->flags & MMAP_ONLY_EVEN) {
175 value >>= 16;
176 }
177 base[offset] = value;
178 } else {
179 *(uint16_t *)(base + offset) = value;
180 }
181 return;
182 }
183 }
184 if ((!(chunk->flags & MMAP_WRITE) || (chunk->flags & MMAP_FUNC_NULL)) && chunk->write_16) {
185 chunk->write_16(offset, context, value);
186 }
187 }
188
157 uint8_t read_byte(uint32_t address, void **mem_pointers, cpu_options *opts, void *context) 189 uint8_t read_byte(uint32_t address, void **mem_pointers, cpu_options *opts, void *context)
158 { 190 {
159 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL); 191 memmap_chunk const *chunk = find_map_chunk(address, opts, 0, NULL);
160 if (!chunk) { 192 if (!chunk) {
161 return 0xFF; 193 return 0xFF;