From Newsgroup: comp.sys.apple2

Hello, all. Apologies if the info I'm seeking is in an FAQ somewhere:
so far, I've found little that helps.

I want to know about the data format used in the Apple cassette
interface (][+, specifically). All I "know" so far is that L is
one cycle of 2kHz, H is one cycle of 1kHz. But actual output from
the Apple seems to be fairly far off from that; and there seems to
be some amount of framing (start/stop bits? parity? CRC?), which I
have not figured out yet. I'd appreciate any more complete info.

BTW, the reason is so that I can build a data loader based on a
PIC processor (for operating the Apple without disk drives).

--Benjamin

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