61 lines
1.1 KiB
Go
61 lines
1.1 KiB
Go
package disk
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type SavedPos struct {
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halfTrack byte
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position int
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}
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type Nybble struct {
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Tracks [][]byte
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halfTrack byte
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position int
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writeable bool
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}
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func NewNybble(tracks [][]byte) *Nybble {
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nd := Nybble{
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Tracks: tracks,
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}
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return &nd
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}
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func (disk *Nybble) Read() byte {
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track := disk.Tracks[disk.halfTrack/2]
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disk.position = (disk.position + 1) % len(track)
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return track[disk.position]
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}
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func (disk *Nybble) Skip(amount int) {
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track := disk.Tracks[disk.halfTrack/2]
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disk.position = (disk.position + amount) % len(track)
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}
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func (disk *Nybble) Write(b byte) {
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track := disk.Tracks[disk.halfTrack/2]
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disk.position = (disk.position + 1) % len(track)
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if disk.writeable {
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track[disk.position] = b
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}
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}
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func (disk *Nybble) SetHalfTrack(halfTrack byte) {
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disk.halfTrack = halfTrack
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}
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func (disk *Nybble) HalfTrack() byte {
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return disk.halfTrack
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}
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func (disk *Nybble) Writeable() bool {
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return disk.writeable
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}
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func (disk *Nybble) GetPos() SavedPos {
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return SavedPos{disk.halfTrack, disk.position}
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}
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func (disk *Nybble) SetPos(pos SavedPos) {
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disk.halfTrack = pos.halfTrack
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disk.position = pos.position
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}
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