60 lines
1.2 KiB
Go
60 lines
1.2 KiB
Go
package core6502
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import (
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"bufio"
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"os"
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)
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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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}
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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 addeessable 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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// 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) {
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// Load file
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f, err := os.Open(filename)
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if err != nil {
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panic(err)
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}
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defer f.Close()
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stats, statsErr := f.Stat()
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if statsErr != nil {
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panic(err)
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}
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size := stats.Size()
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bytes := make([]byte, size)
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buf := bufio.NewReader(f)
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buf.Read(bytes)
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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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}
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