mirror of
https://github.com/ivanizag/izapple2.git
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40 lines
984 B
Go
40 lines
984 B
Go
package apple2
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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 newDisquette16Sector(f *fileNib) *diskette16sector {
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var d diskette16sector
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d.nib = f
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return &d
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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/stepsPerTrack]
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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 / stepsPerTrack
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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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