38 lines
859 B
Go
38 lines
859 B
Go
package apple2
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import (
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"fmt"
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"reflect"
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)
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// memoryPage is a data page of 256 bytes
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type memoryPage interface {
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Peek(uint8) uint8
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Poke(uint8, uint8)
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}
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// pagedMemory represents the addressable space of the processor
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type pagedMemory struct {
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data [256]memoryPage
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}
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// Peek returns the data on the given address
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func (m *pagedMemory) Peek(address uint16) uint8 {
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hi := uint8(address >> 8)
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lo := uint8(address)
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return m.data[hi].Peek(lo)
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}
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// Poke sets the data at the given address
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func (m *pagedMemory) Poke(address uint16, value uint8) {
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hi := uint8(address >> 8)
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lo := uint8(address)
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m.data[hi].Poke(lo, value)
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}
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// SetPage assigns a MemoryPage implementation on the page given
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func (m *pagedMemory) SetPage(index uint8, page memoryPage) {
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fmt.Printf("Assigning page 0x%02x type %s\n", index, reflect.TypeOf(page))
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m.data[index] = page
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}
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