34 lines
854 B
Go
34 lines
854 B
Go
package storage
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/*
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See:
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"Beneath Apple DOS" https://fabiensanglard.net/fd_proxy/prince_of_persia/Beneath%20Apple%20DOS.pdf
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https://github.com/TomHarte/CLK/wiki/Apple-GCR-disk-encoding
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*/
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type diskette16sector struct {
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nib *fileNib
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position int
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}
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func (d *diskette16sector) PowerOn(cycle uint64) {
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// Not used
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}
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func (d *diskette16sector) PowerOff(_ uint64) {
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// Not used
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}
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func (d *diskette16sector) Read(quarterTrack int, cycle uint64) uint8 {
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track := d.nib.track[quarterTrack/4]
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value := track[d.position]
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d.position = (d.position + 1) % nibBytesPerTrack
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//fmt.Printf("%v, %v, %v, %x\n", 0, 0, d.position, uint8(value))
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return value
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}
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func (d *diskette16sector) Write(quarterTrack int, value uint8, _ uint64) {
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track := quarterTrack / 4
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d.nib.track[track][d.position] = value
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d.position = (d.position + 1) % nibBytesPerTrack
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}
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