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55 lines
1.3 KiB
Go
55 lines
1.3 KiB
Go
package core6502
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import "io/ioutil"
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// Memory represents the addressable space of the processor
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type Memory interface {
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Peek(address uint16) uint8
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Poke(address uint16, value uint8)
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// PeekCode can bu used to optimize the memory manager to requests with more
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// locality. It must return the same as a call to Peek()
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PeekCode(address uint16) uint8
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}
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func getWord(m Memory, address uint16) uint16 {
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return uint16(m.Peek(address)) + 0x100*uint16(m.Peek(address+1))
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}
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func getZeroPageWord(m Memory, address uint8) uint16 {
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return uint16(m.Peek(uint16(address))) + 0x100*uint16(m.Peek(uint16(address+1)))
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}
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// FlatMemory puts RAM on the 64Kb addressable by the processor
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type FlatMemory struct {
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data [65536]uint8
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}
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// Peek returns the data on the given address
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func (m *FlatMemory) Peek(address uint16) uint8 {
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return m.data[address]
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}
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// PeekCode returns the data on the given address
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func (m *FlatMemory) PeekCode(address uint16) uint8 {
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return m.data[address]
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}
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// Poke sets the data at the given address
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func (m *FlatMemory) Poke(address uint16, value uint8) {
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m.data[address] = value
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}
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func (m *FlatMemory) loadBinary(filename string) error {
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bytes, err := ioutil.ReadFile(filename)
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if err != nil {
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return err
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}
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for i, v := range bytes {
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m.Poke(uint16(i), uint8(v))
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}
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return nil
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}
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