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From: charles@c3pe.UUCP (Charles Green)
Newsgroups: comp.sys.atari.8bit
Subject: Need information on double-density SIO commands
Keywords: R W P DCOMND DBUFLO/HI
Message-ID: <7097@c3pe.UUCP>
Date: 4 Jun 89 01:41:53 GMT
Organization: C3 Inc, Herndon, VA
Lines: 16

Now that I have an Atari drive that can read and write 256-byte sectors, I'd
like to try accessing floppies from a CP/M machine in our office, which can
write 40-track, single-sided, double density 256-byte sectors.  However, I
haven't been able to successfully use SIO to read the sectors.

I have a BASIC program with machine language assist which can read/write the
standard 128-byte sectors via SIO calls, stuffing 'R' into DCOMND and filling
in the other fields of the DCB for sector number and buffer.  I hoped that by
putting 256 into DBYTLO/HI I would be able to read the sectors, but I only got
data for the first three sectors, which leads me to believe I'm still only
giving the "single-density" read command, and the drive is being tolerant in
case I'm trying to boot from PROM.

So, can anyone shed some light on this issue?  Thanks for any information...
-- 
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