55 lines
960 B
Go
55 lines
960 B
Go
package apple2
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import (
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"encoding/binary"
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"io"
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)
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type memoryRange struct {
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base uint16
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data []uint8
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}
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func newMemoryRange(base uint16, data []uint8) *memoryRange {
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var m memoryRange
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m.base = base
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m.data = data
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return &m
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}
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func (m *memoryRange) peek(address uint16) uint8 {
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return m.data[address-m.base]
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}
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func (m *memoryRange) poke(address uint16, value uint8) {
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m.data[address-m.base] = value
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}
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func (m *memoryRange) subRange(a, b uint16) []uint8 {
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return m.data[a-m.base : b-m.base]
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}
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func (m *memoryRange) save(w io.Writer) error {
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err := binary.Write(w, binary.BigEndian, m.base)
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if err != nil {
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return err
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}
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err = binary.Write(w, binary.BigEndian, m.data)
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if err != nil {
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return err
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}
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return nil
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}
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func (m *memoryRange) load(r io.Reader) error {
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err := binary.Read(r, binary.BigEndian, &m.base)
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if err != nil {
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return err
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}
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err = binary.Read(r, binary.BigEndian, &m.data)
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if err != nil {
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return err
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}
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return nil
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}
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