Re: CBM DOS bug?

From: Greg King <greg.king5_at_verizon.net>
Date: Fri, 01 Aug 2014 01:03:39 -0400
Message-id: <53DB1FAB.70200@verizon.net>
On 2014-07-31 8:35 PM, "Andr Fachat" wrote:
> Hi there,
> I know it's probably well known, but it's later over here... :-)
> I have written (with others) an atmega-based firmware to use as disk
> drive for the PET and other Commodore 8-bit machines.
> During testing of the D64 functionality, I found a small oddity. I used
> VICE with true 4040 disk emulation; and, executed some
> B-A and B-F commands on an image (using a small BASIC test program).
> Our implementation actually has the blocks reserved after running the
> small BASIC test program -- the VICE emulated disk does not.
> It is unchanged from the empty disk it has started with!
> Do you know of this bug? The small test program is here:
> https://github.com/fachat/XD2031/blob/master/fwtests/blockcmd/blkaf1.lst
> Thanks for any help!

Reread this old message:
http://cbm-hackers.2304266.n4.nabble.com/Another-DOS-oddity-tp4656770p4656785.html

Your new symptom is an opposite of the old one; but, they probably are 
related.  I suspect that getting the directory throws away the BAM 
that's in drive RAM.  Therefore, the test program's changes might be 
lost every time it does a "directory".

The fix might be to open "#", "b-a" or "b-f", then close the file before 
doing "directory".


       Message was sent through the cbm-hackers mailing list
Received on 2014-08-01 06:00:02

Archive generated by hypermail 2.2.0.