From: Greg King (gngking_at_erols.com)
Date: 2002-11-21 11:38:02
-----Original Message-----
From: William Levak
Date: Wednesday, November 20, 2002 12:41 AM
Subject: Re: LOAD command (Was: Disk drive questions)
>
> On Mon, 18 Nov 2002, Marko [iso-8859-1] Mäkelä wrote:
>
> > On Sun, Nov 17, 2002 at 11:10:29PM -0500, William Levak wrote:
> > > Even a simple LOAD or SAVE uses the command channel, although you normally
> > > don't see it from BASIC.
> >
> > Are you sure of this? I thought LOAD would be equivalent to OPEN1,8,0,"FILE"
> > and SAVE to OPEN1,8,1,"FILE". I may remember the secondary addresses wrong.
>
> You're right. I did some tests, and the command channel is not affected.
> Apparently, all the result information comes from the status byte.
When a drive cannot open a file successfully, it refuses to move that file's
data.
LOAD attempts to read the first byte (load-address), then it looks at the STATUS
variable. If LOAD sees the read-time-out flag, then it knows that the file
could not be found.
SAVE, on the other hand, has a bug (I wonder how many people noticed this):
it blindly sends the data to the drive -- it does not care whether or not the
drive accepts that data! If you try to save a large file, then you might wait a
long time before you learn that the command did not work.
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