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What about the fact the timing hole was on the wrong side? Wouldn't that have affected the hole reader since it would never be able to read through the disk OR was there a reader on the other side

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> The APPLE DISK is different than most other drives because it ignores the timing hole, using the motor and ‘soft’ timing techniques instead.

I don't know about every machine from that era but neither the C64 or the AppleII used the timing hole, relying on special signals on each track to identify the start of sectors.

Atari didn't need it either. The 1771 (or 2793 I think) floppy controller chip (a standard chip for IBM formatted floppies) does need the index pulse for the write track command for formatting. But the signal is just connected to a GPIO (I think on the 1050 drive this was fed by a timer).

This saves money, eliminating the need for the index pulse LED and photo transistor.

Reads never need the index pulse on soft sector floppies. Each sector has a header with the sector number and an "address mark" (a unique data pattern) used to detect the beginning of each sector and track.

Hmm, except the index pulse may have been used for a timeout if I remember correctly.

Correct. The C64 would just step the motor to the first track -1 and that is the reason for the head banging you got, as well as for the crappy alignment issues.

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