izapple2/memoryRange.go
2019-10-06 01:26:00 +02:00

55 lines
960 B
Go

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