Re: Fast GCR decoding?

From: Michał Pleban <>
Date: Tue, 15 Jan 2013 14:32:04 +0100
Message-ID: <>
Hello! wrote:

> Last night I wrote a new routine completely from scratch, using 2KiB of tables and I seem to get only marginally faster than what is inside 1571, still needing 40+ cycles in case of four out of five GCR bytes (after equalising). I disassembled also quickly DolphinDOS 2 ROM and I seem to have found some rather big tables inside but didn't extract and analysed the actual routines. Especially that Julian recently wrote he could possibly have a look at it.

Can you tell how many cycles do you actually need to decode 5 GCR bytes?
Are you decoding bytes that are already loaded into a buffer, or on the
fly when reading?


       Message was sent through the cbm-hackers mailing list
Received on 2013-01-15 14:00:03

Archive generated by hypermail 2.2.0.