Re: Fast GCR decoding?

From: Michał Pleban <>
Date: Tue, 15 Jan 2013 15:23:13 +0100
Message-ID: <>
Hello! wrote:

> According to my count 186 cycles, although the answer is somewhat more difficult than that: I /would/ need 186 cycles, provided that I would read the incoming bytes off the VIA and be able to decode them on the fly (and the routine is bug-free :-). Since with 40+ cycles on most bytes I can't do it on the fly, I need to read/decode off-the buffer. That would add cycles and put me in the range of 200+ cycles, which is about the same as what 1571 routines do off the buffer.

Ah OK, I thought you meant 40 cycles for the whole 5 bytes, which is
obviously impossible :-) With 186 cycles for a 5 byte buffer, that means
37 cycles per byte, which should not be that hard? Let me think it over
the next days ;-)


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Received on 2013-01-15 15:00:25

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