Microdrive problems... Replace? Junk?

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Peter Hoffman

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Mar 15, 1992, 10:52:38 PM3/15/92
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Hi,

I am very happy to see some QL activity here! I am a huge Sinclair
fan from the old days having cut my teeth on a T/S-1000 and then a
Spectrum. I have a defective QL that I bought just to add to my
collection even though the microdrives are dead. My question is
simple: can I cheaply replace the microdrives or (much better) is
there a floppy interface that is inexpensive? A kit or better yet,
schematics would be best. An interface that supports generic
hard-drives would be unbelievably good.

Thanks for any help and keep those Sinclairs humming!

Peter Hoffman
pe...@epoch.geol.scarolina.edu


Dave Woodman

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Mar 16, 1992, 4:25:29 AM3/16/92
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In article <1992Mar16.0...@opusc.csd.scarolina.edu> Peter Hoffman writes:
>I am very happy to see some QL activity here! I am a huge Sinclair
>fan from the old days having cut my teeth on a T/S-1000 and then a
>Spectrum. I have a defective QL that I bought just to add to my
>collection even though the microdrives are dead. My question is
>simple: can I cheaply replace the microdrives or (much better) is
>there a floppy interface that is inexpensive? A kit or better yet,
>schematics would be best. An interface that supports generic
>hard-drives would be unbelievably good.
>

Obtaining QL spares is no problem if you are prepared to pay postage to and
from the UK; a good range is carried by TK Computerware (addresses will follow).

As for disk interfaces, the best are available from Miracle Systems. Such
interfaces tend to also contain expansion memory, and the Gold Card that
they sell will give you 2M ram with a 16MHz 68000 to boot.

These guys also sell a hard-disk, although (since the demise of Rebel) I
don't know of a stand-alone hard-disk interface. This needn't bee too much
of a bind though:- with the gold card you can use extra-high density disks
(3.2M).

OK, now for the addresses:-

TK Computerware, Miracle Systems,
Stone St, 25 Broughton Way,
North Stanford, Osbaldwick,
Ashford, York.
Kent.

TN25 6SF YO1 3BG

Tel +44 303 812801 +44 904 423986
FAX +44 303 812892

Hope this helps,

Dave.

--
==============================================================================
= My e-mail address might be woo...@bnr.ca, but Maidenhead is definitely =
= in Britain... My employer is entitled to disagree with anything but this! =
==============================================================================

Max Cray

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Mar 18, 1992, 10:53:02 PM3/18/92
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pe...@opusc.csd.scarolina.edu (Peter Hoffman) writes:

> Hi,
>
> I am very happy to see some QL activity here! I am a huge Sinclair
> fan from the old days having cut my teeth on a T/S-1000 and then a
> Spectrum. I have a defective QL that I bought just to add to my

I too have several TS-1000's and TS-2068. Maybe its time for:
alt.sys.sinclair, or alt.sys.ql?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-= Max Cray =-
Net: underg%m...@uunet.uu.net Support
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Data: The Underground Computing Foundation BBS Software
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CI$: 76334,2203

Sander Plomp

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Mar 20, 1992, 8:55:03 AM3/20/92
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pe...@opusc.csd.scarolina.edu (Peter Hoffman) writes:

>I am very happy to see some QL activity here! I am a huge Sinclair
>fan from the old days having cut my teeth on a T/S-1000 and then a
>Spectrum. I have a defective QL that I bought just to add to my
>collection even though the microdrives are dead. My question is
>simple: can I cheaply replace the microdrives or (much better) is
>there a floppy interface that is inexpensive? A kit or better yet,
>schematics would be best. An interface that supports generic
>hard-drives would be unbelievably good.

>Peter Hoffman
>pe...@epoch.geol.scarolina.edu

If you plan to use the QL for anything other simpleminded games
and demos I would forget about the microdrives and get a floppy.

Compared to floppies the microdrives are very slow, have very limited
capacity, are expensive, hard to come by and, above all, they are
very, very unreliable. In addition, there are programs to read/write
floppies in MS-DOS format which makes is a lot easier to share
data with the rest of the world. When I switched to floppies
a whole new world opened up. The machine became some much more
powerful that I can't imagine that I ever did without.

I know of no kits or schematics for a floppy interface. I guess the
the hardware design isn't too difficult but writing a good floppy
device driver takes a lot of time. Trying to do it all by yourself
isn't very worth it so nobody has done it. I guess the same goes
for hard disk interfaces. You could copy an commercial interface
and use the same device driver. But that is illegal and pointless
since the money saved isn't worth the trouble you have getting it
working. (If you like that kind of trouble it is better spend
building hardware not commercially available.)

If you want to keep it cheap look for second hand stuff. A lot of
people are upgrading either from QL to non-extinct machines or
from older disk interfaces to one of the newer ones (like the Goldcard).
If you have access to some kind of QL/sinclair group are magazine
you might be able to find something cheap.

Commercial interfaces may also provide other advantages. For example,
many have a part of the Tony Tebby toolkit in their ROM which gives
you lots of useful new BASIC commands, operating system extensions
and bug fixes. Some have extra memory which is very useful - not only
because you can run bigger programs but also because you can multitask
more programs and for RAMdisks. There are some ramdisk drivers which
dynamically adjust their size and it works really great, I use one
all the time. You really can't have enough memory.

I hope you get your Ql running,

<Sander Plomp>
--
Sander Plomp
Internet: san...@cwi.nl
Fidonet: 2:283/500.4

Adam David

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Mar 21, 1992, 2:45:21 PM3/21/92
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woo...@bmdhh213.tmc.edu (Dave Woodman) writes:

>In <1992Mar16.0...@opusc.csd.scarolina.edu> Peter Hoffman writes:

>>I am very happy to see some QL activity here!

Yes, it was a pleasant surprise to see more QL related articles here than
anything else.

>>I have a defective QL that I bought just to add to my
>>collection even though the microdrives are dead. My question is
>>simple: can I cheaply replace the microdrives or (much better) is
>>there a floppy interface that is inexpensive? A kit or better yet,
>>schematics would be best. An interface that supports generic
>>hard-drives would be unbelievably good.

Tony Firschman Services sell microdrive mechanisms for around 20 pounds (see
address etc in another posting). It is worth having one functional microdrive
for loading things off microdrive and sharing with other QL users, who don't
necessarily have floppies. I confer that microdrives are junk though.

> As for disk interfaces, the best are available from Miracle Systems. Such
>interfaces tend to also contain expansion memory, and the Gold Card that
>they sell will give you 2M ram with a 16MHz 68000 to boot.

The new floppy interfaces from Miracle (including the GoldCard) support all
available 5.25" and 3.5" mechanisms including the newest ED types, giving
3600kB per disk. CST used to make a general purpose SCSI harddisk interface,
but they have been out of business for some time. No doubt other companies
will be producing SCSI cards in the near future, I would not be surprised to
see ethernet cards either.

The QL is alive and well, don't let anyone convince you otherwise.

--
Adam David.
(ad...@rhi.hi.is)

Adam David

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Mar 21, 1992, 2:52:34 PM3/21/92
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--
Adam David.
(ad...@rhi.hi.is)

Max Cray

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Mar 23, 1992, 3:05:51 PM3/23/92
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pe...@opusc.csd.scarolina.edu (Peter Hoffman) writes:

> I believe that alt.sys.sinclair would be good. Mauricio Tavares has
> been running a mailing list (maur...@gauss.aero.ufl.edu for more
> info) on Sinclairs for several months now and traffic is sporadic. An
> alt group would be a nice step up since I believe the lack of traffic
> is due to the lack of awareness of the list.
>
> The charter was to cover Sinclair products since there were probably
> not enough people to warrant a 2068 or QL group alone. Many people
> followed the entire series of Sinclairs. It also affords the
> opportunity to discuss other Clive Sinclair products past and future.

I vote 'YES'.

Jonathan Spencer

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Mar 24, 1992, 8:57:04 AM3/24/92
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san...@cwi.nl (Sander Plomp) writes:
[snip]

>In addition, there are programs to read/write
>floppies in MS-DOS format which makes is a lot easier to share
>data with the rest of the world.

Is there a program to write QL files onto a MSDOS disk? I have one which
claims to READ them, but right now I need one to WRITE them. Any
suggestions?

===========================================================================
From : Jonathan M Spencer
Mail : Computing Lab., University of Newcastle-upon-Tyne, NE1 7RU, England
Phone : +91 222 8229
ARPA : J.M.Spencer%newcast...@cs.ucl.ac.uk
JANET : J.M.S...@uk.ac.newcastle
UUCP : !uknet!newcastle.ac.uk!J.M.Spencer
===========================================================================

Dave Woodman

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Mar 25, 1992, 4:17:00 AM3/25/92
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In article <1992Mar24....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>
>Is there a program to write QL files onto a MSDOS disk? I have one which
>claims to READ them, but right now I need one to WRITE them. Any
>suggestions?

Yes, there is at least one program to do this that I know of:- Media
Manager Special Edition from Digital Precision. This product offers file
recovery, directory management, sector/disk editors etc and the ability
to write to and read from MSDOS and TOS disks. Only one caveat:- you can
only process files in the top-level directory:- sub-directories will be
shown but their files will not be accessible.

Jonathan Spencer

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Mar 26, 1992, 6:21:25 AM3/26/92
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woo...@bnr.ca (Dave Woodman) writes:

>In article <1992Mar24....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>>
>>Is there a program to write QL files onto a MSDOS disk? I have one which
>>claims to READ them, but right now I need one to WRITE them. Any
>>suggestions?

> Yes, there is at least one program to do this that I know of:- Media
>Manager Special Edition from Digital Precision. This product offers file
>recovery, directory management, sector/disk editors etc and the ability
>to write to and read from MSDOS and TOS disks. Only one caveat:- you can
>only process files in the top-level directory:- sub-directories will be
>shown but their files will not be accessible.

I've got SMM, but this version only converts DOS files to QDOS, not the
other way. (Bit of an oversight really.) As it costs ~L40 and I'm
leaving the QL scene, I don't want to spend that kind of money. I have
another alternative which is a serial cable from ser2 on the QL to com2
on the PC. Just need to resolder it for a 9 pin plug.

Mark Roe

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Mar 26, 1992, 7:42:14 AM3/26/92
to
>In article <1992Mar24....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>>
>>Is there a program to write QL files onto a MSDOS disk? I have one which
>>claims to READ them, but right now I need one to WRITE them. Any

I assume it is text files you are talking about. I have been
able to copy simple ascii text files - written with quill - to IBM
format in the following way.

Write a simple printer driver that has nothing for all the
special typefaces etc, and uses CR,LF for end of lines. "Print" your file
to an mdv ( or disk). Use a utility that comes with digital
Precision's "Conqueror" to copy the file from mdv to MSDOS format disk.
(I think it is called "Discover") I have to use an mdv file since I
have only one disk drive. Editors of various journals have been able
to make use of articles produced this way. I'm a bit vague since the
relevent disks are back in Canada.

Howard Clase

Dave Woodman

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Mar 26, 1992, 10:15:29 AM3/26/92
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In article <1992Mar26....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>woo...@bnr.ca (Dave Woodman) writes:
>
>>In article <1992Mar24....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>>>
>>>Is there a program to write QL files onto a MSDOS disk? I have one which
>>>claims to READ them, but right now I need one to WRITE them. Any
>>>suggestions?
>
>> Yes, there is at least one program to do this that I know of:- Media
>>Manager Special Edition from Digital Precision. This product offers file
>>recovery, directory management, sector/disk editors etc and the ability
>>to write to and read from MSDOS and TOS disks. Only one caveat:- you can
>>only process files in the top-level directory:- sub-directories will be
>>shown but their files will not be accessible.
>
>I've got SMM, but this version only converts DOS files to QDOS, not the
>other way. (Bit of an oversight really.) As it costs ~L40 and I'm
>leaving the QL scene, I don't want to spend that kind of money. I have
>another alternative which is a serial cable from ser2 on the QL to com2
>on the PC. Just need to resolder it for a 9 pin plug.
>

MMSE is available as an upgrade to SMM, although I don't know the cost
of the upgrade offhand:- is this the ~L40 to which you refer? If not then
it might be worth having a chat with DP to check.

If the upgrade is still too pricey, see if you can find a local victim
to convert your files for you:- an enquiry through the good offices of
QUANTA may yield results.

Linus Benedict Torvalds

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Mar 26, 1992, 2:20:18 PM3/26/92
to
In article <1992Mar26....@newcastle.ac.uk> J.M.S...@newcastle.ac.uk (Jonathan Spencer) writes:
>
>I've got SMM, but this version only converts DOS files to QDOS, not the
>other way. (Bit of an oversight really.) As it costs ~L40 and I'm
>leaving the QL scene, I don't want to spend that kind of money. I have
>another alternative which is a serial cable from ser2 on the QL to com2
>on the PC. Just need to resolder it for a 9 pin plug.

The QL serial lines have serious problems: I never got them to work ok
even at 2400bps, and it probably gets worse at the higher speeds. The
problem seems to be hardware-related: at least on my machine the QL
didn't correctly receive (about 1% error-rate at 2400bps with a 100%
good line). I've got the impression it was the 8049 chip programming
that sampled the input pin at the start of a bit instead of the middle
of the incoming bit. Maybe it has been corrected on newer QL's?

If you want to convert QL floppies to IBM format, it's relatively easy
from the IBM end: I wrote a simple program for it in Turbo-C, and never
had any problems. Actually writing DOS disks from a QL shouldn't be
that difficult, but I never got around to it: I made my own floppy
driver that was able to read DOS-disks (no directories), but I didn't
write anything (it was transparent but slow: "copy dos1_file to
mdv1_file" worked correctly without any programs needed).

Sadly, I have none of the above programs any more: I changed over to the
386 last January, and didn't save any of the old programs (I also moved
away from DOS within a month or two, so I don't even have the QL-read
program for the PC). The QL file structure is pretty simple, though,
and reading it from DOS is much less painful than using serial lines (it
is also well documented: there were some QL World articles that did a
nice dive into the disk layout).

Linus

BTW: anybody notice the QDOS bug where you aren't allowed to touch A5 in
the polling-routines, as it can crash the machine if there is a
task-switch at the same time? Not an easy one to find: took me a couple
of days of kernel disassembly to notice that the register was
incorrectly saved. That was while doing the floppy-driver, and I was
close to giving up on the whole thing. Don't remember the version
number of QDOS. Details may be hazy: it has been some time.

Adam David

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Apr 5, 1992, 3:42:27 PM4/5/92
to
[following up on 3 articles with the same subject to save header bandwidth]

quote Dave Woodman:


> Yes, there is at least one program to do this that I know of:- Media
>Manager Special Edition from Digital Precision. This product offers file
>recovery, directory management, sector/disk editors etc and the ability
>to write to and read from MSDOS and TOS disks. Only one caveat:- you can
>only process files in the top-level directory:- sub-directories will be
>shown but their files will not be accessible.

If they have not fixed this by now, I wonder what Digital Precision are up to.
MMSE is supposed to be able to transfer files both to and from DOS directories.
DP must have reasonable trade from the QL market since they are still placing
full-spread ads in QL World.

quote Howard Clase:


>Use a utility that comes with digital
>Precision's "Conqueror" to copy the file from mdv to MSDOS format disk.
>(I think it is called "Discover")

The program bundled by DP is probably a cut down version of Super Media Manager.
It is easier (and has more sales potential) to give away half of one of your own
products than to include someone else's.
DiscOver is about the best transfer utility that I know of. This is the one that
I use most, though sometimes it is more convenient to use the Media Manager
utility that came with Conqueror or the AtariST transfer command built into the
ST-QL emulator. Multi-DiscOver can transfer QL files to disks of BBC, CP/M and
various other interesting formats.

quote Linus Torvalds:


>The QL serial lines have serious problems: I never got them to work ok
>even at 2400bps, and it probably gets worse at the higher speeds. The
>problem seems to be hardware-related: at least on my machine the QL
>didn't correctly receive (about 1% error-rate at 2400bps with a 100%
>good line). I've got the impression it was the 8049 chip programming
>that sampled the input pin at the start of a bit instead of the middle
>of the incoming bit. Maybe it has been corrected on newer QL's?

I don't think the 8049 firmware was ever changed, but some of the TTL glue
logic was put on a PAL and a few discrete components changed. The only serious
failing in the standard QL serial port is that it cannot receive at 19200 baud
at all, and is only fast enough to receive 9600 baud with 2 stop bits. Maybe
you had a faulty machine or the hardware handshaking was somehow incorrect (?).

Linus mentioned giving up the QL for a PC, and then giving up DOS altogether.
(The second was undoubtably a wise move :)
There are two alternative solutions to the first move, either get a PC card for
the QL or a QL on a card for the PC. I am pretty sure these things have both
been produced. Of course on an AtariST or an Amiga, use a QL emulator. I would
not be surprised to see a Macintosh version shortly. Whatever people say, the
QL simply refuses to die. If it had been made in the first place with a better
keyboard and disks as standard instead of microdrives, it would have given the
competition a far better run for its money. The machine concept and operating
system were at least 5 years ahead and QDOS is still a viable OS.

--
Adam David
(ad...@rhi.hi.is)

Linus Benedict Torvalds

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Apr 9, 1992, 9:23:04 AM4/9/92
to
In article <47...@krafla.rhi.hi.is> ad...@rhi.hi.is (Adam David) writes:
>quote Linus Torvalds:
>>The QL serial lines have serious problems: I never got them to work ok
>>even at 2400bps, and it probably gets worse at the higher speeds. The
>>problem seems to be hardware-related:
[ deleted ]

>I don't think the 8049 firmware was ever changed, but some of the TTL glue
>logic was put on a PAL and a few discrete components changed. The only serious
>failing in the standard QL serial port is that it cannot receive at 19200 baud
>at all, and is only fast enough to receive 9600 baud with 2 stop bits. Maybe
>you had a faulty machine or the hardware handshaking was somehow incorrect (?).

Well, it might have been only my machine, although I had some contact
with other QL users, some of which confirmed my problems. I'm not
saying the QL isn't a nice machine: the 68000 beats the 80x86 (x < 3)
family outright, and QDOS is a much better system than DOS ever will be.
There were a couple of problems:

- it's not supported very well outside of England: in Finland it was
definitely hard to get things for it (had to use mailorder to England
etc). I never got any real software except the original GST Assembler,
and that one didn't have very many features (no macros, no linker - I
corrected the first one by writing my own, but I never got a linker for
the QL).

- a bitmapped screen as big as the one the QL has definitely needs more
processing power than a 8MHz 68008 can handle. I had to rewrite the
character-output routines in assembly in order to get a nice editor that
didn't fall behind every time I scrolled heavily, and I had problems
keeping up with text at 2400 bps.

- the hardware was pretty flaky - it overheated easily, and running
assembly programs from basic ram was definitely slower than running them
from EPROM (I had my own assembler/editor-system on eprom - only way to
live as I didn't have a disk-drive originally - and it gave me that
extra 50kB of ram)

>Linus mentioned giving up the QL for a PC, and then giving up DOS altogether.
>(The second was undoubtably a wise move :)

I have to say I like the first move too - without DOS a 386-machine is
so much faster and easier to use then the QL ever was (I can feel the
flames coming...). There was no unix available for the QL when I last
looked, and although QDOS does multitask, unix is still nicer. (and no,
I didn't feel like writing my own unix for the QL - it was hard enough
for a 386, which supports it better :^)

> If it had been made in the first place with a better
>keyboard and disks as standard instead of microdrives, it would have given the
>competition a far better run for its money. The machine concept and operating
>system were at least 5 years ahead and QDOS is still a viable OS.

Agreed. Whatever you say about Sir Clive, he certainly put out
interesting machines - even if they had their quirks. I still have my
QL, although I haven't taken it out for a long time.

Linus

Dave Woodman

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Apr 9, 1992, 12:44:08 PM4/9/92
to
In article <1992Apr9.1...@klaava.Helsinki.FI> torv...@klaava.Helsinki.FI (Linus Benedict Torvalds) writes:
>
> ... There was no unix available for the QL when I last

>looked, and although QDOS does multitask, unix is still nicer. (and no,
>I didn't feel like writing my own unix for the QL - it was hard enough
>for a 386, which supports it better :^)
>

Well (and Linus, you might not want to hear this, given your recent
efforts), there is Minix available for QDOS...

Most of your other problems have since been fixed, including the problem
with lack of power, and further developments are close. The only thing
left is the problem of the RS232 interface giving problems. For a clue to
this, watch the handshake used on receive:- this is not held steady, even
on an idle line.

Cheers,

Linus Benedict Torvalds

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Apr 10, 1992, 6:49:26 PM4/10/92
to
In article <1992Apr09.1...@bnr.uk> woo...@bnr.ca (Dave Woodman) writes:
>
> Well (and Linus, you might not want to hear this, given your recent
>efforts), there is Minix available for QDOS...

Oh yes, I'm definitely interested - especially if it is available as
patches against PC-minix (but I assume they started off with a 68k
port?). Can somebody tell me how they did it? (and who are "they"
anyway?) I know writing a floppy-driver wouldn't be much fun: with no
DMA I had to really optimize things in order to read the programmed IO
for my own driver, and I think I never got it to work from basic ram
(had to use eproms or expansion-ram - the inner loops that read the IO
addresses were really tight: I was unable to use a cmp, had to use a
subq, I think, to save a couple of cycles. Something like that...
Debugging was hell :^).

Or does it all work on top of QDos? Much easier, but not as much fun.
But it /would/ be fun to refer to the microdrives as /dev/rmt0 :)

Does QL-minix use the QDOS for multitasking too? Or does it use it's own
scheduler within one QL task or what? Running atop QDOS should mean you
can run minix while at the same time using SB and any other QL tasks -
true or false?

> Most of your other problems have since been fixed, including the problem
>with lack of power, and further developments are close.

Well, there were newer versions of the QL coming out even while I was
still active, so I'm not too surprised - with a reasonably fast 68020 or
better and a better memory subsystem it might be a real pleasure to use.
I always liked QDos - one of my few gripes with it was the inability to
use the second screen without disabling most of the system software (and
being unable to map all the interrupts - I'd have liked to use the a-
and f-line exceptions and some other things...)

> The only thing
>left is the problem of the RS232 interface giving problems. For a clue to
>this, watch the handshake used on receive:- this is not held steady, even
>on an idle line.

If this was in the original specs, it might explain my problems: I never
had access to an oscilloscope to test it all out. It's a bit ironic
that this would still be a problem - serial lines aren't exactly hard to
handle, and it's a pity the QL didn't use more standard parts for them.
Some of the hardware solutions in the QL were definitely "interesting" -
I assume it was cheaper that way originally, but it did hurt the
reputation of the machine.

I fixed some of my problems with a better power-supply and regulator
(home-brew, but they seemed to work), as well as additional heat-
dissipation. A pity really: I shouldn't have needed to, and I had a
number of weird crashes before I got it all together.

Linus

Dave Woodman

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Apr 11, 1992, 8:31:22 AM4/11/92
to
In article <1992Apr10.2...@klaava.Helsinki.FI> torv...@klaava.Helsinki.FI (Linus Benedict Torvalds) writes:
>In article <1992Apr09.1...@bnr.uk> woo...@bnr.ca (Dave Woodman) writes:
>>
>> Well (and Linus, you might not want to hear this, given your recent
>>efforts), there is Minix available for QDOS...
>
>Oh yes, I'm definitely interested - especially if it is available as
>patches against PC-minix (but I assume they started off with a 68k
>port?). Can somebody tell me how they did it? (and who are "they"
>anyway?) I know writing a floppy-driver wouldn't be much fun: with no

'They' is a him. The particular 'him' in question is Dave Walker
(d.j.walke...@oasis.icl.co.uk). And yes, it used to be ST Minix,
but it's getting better now...

>DMA I had to really optimize things in order to read the programmed IO
>for my own driver, and I think I never got it to work from basic ram
>(had to use eproms or expansion-ram - the inner loops that read the IO
>addresses were really tight: I was unable to use a cmp, had to use a
>subq, I think, to save a couple of cycles. Something like that...

B


>Debugging was hell :^).
>
>Or does it all work on top of QDos? Much easier, but not as much fun.
>But it /would/ be fun to refer to the microdrives as /dev/rmt0 :)

Yes again, it is implemented as a job under QDOS. I'm still waiting for my copy,
but apparently you have the choice of writing to devices directly, or using a
QDOS file as a 'partition,' ie, the system sees the file as a device. With my
hardisk and Gold Card (16 MHz 'proper' 68000 and 2M RAM) this should serve
quite nicely...

>
>Does QL-minix use the QDOS for multitasking too? Or does it use it's own
>scheduler within one QL task or what? Running atop QDOS should mean you
>can run minix while at the same time using SB and any other QL tasks -
>true or false?
>

As I say, I don't have my copy yet, but I would imagine that it uses it's own
scheduler. And yes, the author tells me that SB would be available, dependant
on how much memory has been allocated to Minix. This might prove to be a
problem on a 640K QL, but should prove quite possible on one with 896K (Trump
Card) or 2M (Gold Card).

>> Most of your other problems have since been fixed, including the problem
>>with lack of power, and further developments are close.
>
>Well, there were newer versions of the QL coming out even while I was
>still active, so I'm not too surprised - with a reasonably fast 68020 or
>better and a better memory subsystem it might be a real pleasure to use.
>I always liked QDos - one of my few gripes with it was the inability to
>use the second screen without disabling most of the system software (and
>being unable to map all the interrupts - I'd have liked to use the a-
>and f-line exceptions and some other things...)
>

The second screen is available under the Minerva ROM:- re-written QDOS. The
Gold Card (again) shadows the internal RAM so making the basic QL hardware
much less relevant to the user. I'm afraid that the original set of 'mappable'
vectors remains the same, although QUANTA will supply you with a disk
containing a disassembly of the ROMs with which you may do as you will. With
then new QL compatible coming from Miracle soon, you won't be forced to use
a lowely 68020 either:- they wern't impressed with the improvemant over the
Gold Card...

>> The only thing
>>left is the problem of the RS232 interface giving problems. For a clue to
>>this, watch the handshake used on receive:- this is not held steady, even
>>on an idle line.
>
>If this was in the original specs, it might explain my problems: I never
>had access to an oscilloscope to test it all out. It's a bit ironic
>that this would still be a problem - serial lines aren't exactly hard to
>handle, and it's a pity the QL didn't use more standard parts for them.
>Some of the hardware solutions in the QL were definitely "interesting" -
>I assume it was cheaper that way originally, but it did hurt the
>reputation of the machine.

Even this had a fix long ago:- an intelligent RS232 interface from Tandata.
This beastie is called the QCONNECT, and allows split-baud, gives you the
ability to set a speed other than the main port speed, and provides a much
fuller RS232 signal set.

>
>I fixed some of my problems with a better power-supply and regulator
>(home-brew, but they seemed to work), as well as additional heat-
>dissipation. A pity really: I shouldn't have needed to, and I had a
>number of weird crashes before I got it all together.

Crashing was never one of my problems (unless I coded badly!), but the various
ways of stopping these have been well documented for those of us that suffer.
I agree, though, you shouldn't have needed to put in the work.
>
> Linus

Anyway, to give you an idea, here I am at home, in front of my trusty QL (no
other computers here!), 16MHz 68000 CPU, 2M RAM, Tandata QCONNECT chatting to
my modem at 2400 baud, 40M hard disk, and yes, it is a pleasure to use. Oh,
I have a 'real' keyboard on it too! All I need to do now is get some ED floppy
drives...

Adam David

unread,
Apr 19, 1992, 9:56:03 AM4/19/92
to
woo...@bnr.ca (Dave Woodman) writes:
>torv...@klaava.Helsinki.FI (Linus Benedict Torvalds) writes:
>>[...]

>'They' is a him. The particular 'him' in question is Dave Walker
>(d.j.walke...@oasis.icl.co.uk). And yes, it used to be ST Minix,
>but it's getting better now...

Well done Dave Walker! Also there is a version by Felix Croes, which is not
quite available yet, but exists and works. As soon as I find the time to clean
up the keyboard initialisation so that it works on my Thor XVI development
machine, I will be able to do something with it. Actually, what we need is
one version, not two. Therefore I suggest that we consolidate the effort and
unite the two versions into one.
xD


>>Or does it all work on top of QDos? Much easier, but not as much fun.
>>But it /would/ be fun to refer to the microdrives as /dev/rmt0 :)

This version runs on top of QDOS, currently taking over the whole machine
(exec_w) :( but with clear plans for implementing minix as an OS server
process, such that each minix task would be a QDOS job scheduled under QDOS. :)
Under this arrangement, all tasks are owned by QDOS so all free memory is
dynamically available to any native QDOS job or minix task that needs it, and
piping between minix and QDOS programs is as easy as it should be.
Current devices supported are ttys (console/serial), and a floppy driver which
supports physical sectors or virtual partitions stored in any QDOS file on any
media (with microdrives as a special case).

[about shaky hardware]


>>I fixed some of my problems with a better power-supply and regulator
>>(home-brew, but they seemed to work), as well as additional heat-
>>dissipation. A pity really: I shouldn't have needed to, and I had a
>>number of weird crashes before I got it all together.

>Crashing was never one of my problems (unless I coded badly!), but the various
>ways of stopping these have been well documented for those of us that suffer.

In case this has not been mentioned here before, replacing all TTL chips with
their HCT equivalents will considerably improve the hardware stability, due
to reduced power consumption and improved noise-immunity on the signal lines.

>Anyway, to give you an idea, here I am at home, in front of my trusty QL (no
>other computers here!), 16MHz 68000 CPU, 2M RAM, Tandata QCONNECT chatting to
>my modem at 2400 baud, 40M hard disk, and yes, it is a pleasure to use. Oh,
>I have a 'real' keyboard on it too! All I need to do now is get some ED floppy
>drives...

Fly the flag, Dave!

--
Adam David.
(ad...@rhi.hi.is)

Dave Woodman

unread,
Apr 20, 1992, 2:22:09 PM4/20/92
to
In article <47...@krafla.rhi.hi.is> ad...@rhi.hi.is (Adam David) writes:
>
>Well done Dave Walker! Also there is a version by Felix Croes, which is not
>quite available yet, but exists and works. As soon as I find the time to clean
>up the keyboard initialisation so that it works on my Thor XVI development
>machine, I will be able to do something with it. Actually, what we need is
>one version, not two. Therefore I suggest that we consolidate the effort and
>unite the two versions into one.

I shall forward your article to Dave Walker:- he doesn't presently get
comp.os.misc. You may also wish to email him (address in last posting).

>Fly the flag, Dave!

Don't worry, Adam, I shall!

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