ruud.baltissen_at_apg.nl
Date: 2008-04-15 07:57:31
Hallo Jim,
> But, I like Craig's idea in another context. Use u0>h* to
> move to different virtual "heads" in the partition.
1) The problem is that we HAVE to write 512 bytes when writing a sector.
So when writing a sector of 356 bytes, we first have to read the whole
512 bytes sector (but we save only the 256 bytes of the other sector)
and then write both sectors back to the disk. The problem is the memory
for the "hidden" sector. There are programs, database PRGs most of the
time, that eat up all the buffers, thus leaving us with no buffer to
temporary saving that extra sector.
2) You cannot copy files from one "head" to the other "head" in a normal
way.
Then I rather prefer a FS that knows about this extra sector and will
reserve memory for it as needed. And running the risk that some PRGs
find themself with less buffers then expected.
The above strengthes my opinion to add some extra RAM when using the
16-bits interface. Piggybacking another 2KB SRAM and, to keep it simple,
only using 1 KB of it, solves the problem. Someone able to add the IDE
interface should be capable of adding this SRAM as well IMHO. And with a
bit of luck I can program the FS so that it has at least two extra
buffers available.
> You could use u0>h1 to access a completely new set of 256
> partitions as a different drive, using the same drive number.
That's what I'm doing using the CP command, the same one as used in CMD
drives. @CP:5 for example swithes to partition 5.
--
___
/ __|__
/ / |_/ Groetjes, Ruud
\ \__|_\
\___| URL: Ruud.C64.org
De informatie in dit e-mailbericht is vertrouwelijk en uitsluitend bestemd voor de
geadresseerde. Wanneer u dit bericht per abuis ontvangt, verzoeken wij u contact op te
nemen met de afzender per kerende e-mail. Verder verzoeken wij u in dat geval dit
e-mailbericht te vernietigen en de inhoud ervan aan niemand openbaar te maken.
Wij aanvaarden geen aansprakelijkheid voor onjuiste, onvolledige dan wel ontijdige
overbrenging van de inhoud van een verzonden e-mailbericht, noch voor daarbij
overgebrachte virussen.
APG NV te Heerlen is ingeschreven in het handelsregister Limburg onder nummer 14099617.
The information contained in this e-mail is confidential and may be privileged.
It may be read, copied and used only by the intended recipient.
If you have received it in error, please contact the sender immediately by
return e-mail; please delete in this case the e-mail and do not disclose it's
contents to any person. We don't accept liability for any errors, omissions,
delays of receipt or viruses in the contents of this message which arise as a
result of e-mail transmission.
APG NV, Heerlen, is registered in the trade register Limburg, The Netherlands no. 14099617.
Message was sent through the cbm-hackers mailing list
Archive generated by hypermail pre-2.1.8.