[Coco] CoCo3 and OS-9

[Willard Goosey]

>Date: Wed, 21 Sep 2005 08:06:04 -0700
>From: Andrew <keeper63 at cox.net>

>With all this talk about the OS-9 and such, I thought I would ask, 
>partially for my benefit as well as for others who may not have given it 
>as much thought as myself - how do you set up a real (and/or emulated) 
>CoCo with OS-9?

Well, I don't know about Level I on the CoCo 1 or 2, and I don't do
much with emulators.

On the CoCo 3, You REALLY want 512K and a couple of 360K disk drives.
You may need a PC with a 360K drive for handling .dsk files.  A 720K
floppy drive can be very useful.  If you want do use a serial port,
you'll need an RS-232 pak, and that means you'll also need an MPI --
one upgraded for CoCo 3 use.  If you're planning on using a hard
drive, you'll probably need the MPI anyway.

In Short:
1) Follow the directions on www.nitros9.org to download the
appropriate version onto a PC with a 360K drive.  Follow the
directions to write the .dsk files onto real disks.  If you have a
fairly normal setup, you'll be able to boot off that.

2) Make backups, then, if necessary, use the scripts and standard.bl
to build a custom boot disk.  If you know what hardware you hooked to
your CoCo is, the hardest part of this will probaby be using the line
editor without any real docs on it. :-(

>I would be interested in both setting it up with floppy drives (and
>RAM disk?) and/or hard drives. Do you need a floppy drive to use a
>hard drive?

A floppy drive is (except for DriveWire and old B&B systems)
mandatory.  Maybe even then, I've never used DriveWire and I don't
know if you can boot off it.  Even without a hard drive, I rarely used
a RAM disk.

>What do you need to use a hard drive (I know at one time there 
>were MFM and SCSI adaptors for the CoCo, presumably you could use one of 
>those if you can find one - or, use one of the IDE adaptors from Cloud-9?).
>
You use a hard drive under OS-9 for the same reason you use one on any
other system.  It's faster and larger.

Now, I have to admit, if you use NitrOS-9 (even the 6809 version) or a
hand-hacked OS-9, the speed isn't such an issue.  The stock drive
descriptors use a 30 millisecond step rate.  Most drives are perfectly
happy with 6ms.  You wouldn't think it would make a difference, but
damn it does!!!!  

The size of a hard drive is also nice, less flipping disks.  One
factor here is that OS-9 has utilities to deal with it's own virtual
disk images -- if you have an OS-9 drive large enough to hold one.  

I'm not sure, even if it's possible, you'd want to run a CoCo OS-9
setup without any removable storage for backup.  The RBF filesystem
seems kind of fragile, needs a lot of hand maintaince.  Keep lots of
backups!

>Recently there was discussion on booting OS-9 from the hard drive - I 
>didn't follow it too closely, but it seems that this is a difficult 
>thing to set up (?)

Well, booting soley off a hard drive means that you have a replacement
for your disk controller ROM that knows about the hard drive.  Burke &
Burke, HDB-DOS, whatever.

A simpler setup, with both floppy and hard drives is to start booting
off floppy, then once OS-9 itself is loaded and running, finish the
boot-up sequence off the hard drive.  This is what I do, and I didn't
have any particular problems setting it up.

>What about a real-time clock - is this a needed thing, or a luxury? 

OS-9 likes to know about what time it is.  Rather this is important to
you or not, depends on you.  A RTC is only necessary if you want
accurate time-stamps and you're too lazy to type in the time at
boot-up.  (Or if you're using it embedded or something! :)  

Some clock drivers check the RTC at boot-up and leave it alone after
that, some check on a regular basis after that -- Halting floppy
controllers (most of them!) make the system clock loose time.

>I suppose it depends on what is planned to be done with the
>system. How about extra memory? We know 512K is a comfortable
>"minimum" - but can it be done with only 128K (maybe with a hard
>drive or external RAM drive)?  

Level II will run on 128K... Most of the big apps will even run.  But
don't expect to have much running at the same time, like, say,
Multivue *and* a big app.  512K is very happy.  If it's a choice
between a hard drive and 512K, I'd say go with the memory.  If you're
willing to flip the disks, you have an infinite amount of drive
space, but the RAM in the machine is all the RAM you get!

>Or setup on a CoCo 2 system? Is it possible (today) to get larger
>expansion memory (like you could in the day up to 2 meg)? From where
>(Cloud-9?)...?
>
Cloud-9's working on a 2Meg board, I believe.

>How about where you get the software? Can you still buy it and/or 
>multi-vue and other packages? 

I think Tandy/Radio Shack's supplies have dried up, or been dumped.
Most of their software is available used, here, on ebay, other
sources like that.

>I was looking at the rtsi archive, and noticed some stuff there - can
>this be used to set up a system?

If you meant the OS9/OS-9_6X09 stuff, there's not a complete system
there, but there's lots of stuff so good as to be almost necessary for
a OS-9 machine to get real work done.  As for certain archives of disk
images, that depends on how much you care about having a legal system.

>What about the free (open source? freeware?) OS-9 reimplementation
>(can't remember the name)?

NitrOS-9.  www.nitros9.org has it.  Level I, Level II, 6809 and 6309
versions.  There is also a lot of stuff on RTSI, as you've noticed,
and LOTS of goodies at maltedmedia.com

>Is there a freeware multi-vue? 

Most of the pieces of multi-vue have free replacements.  The only
important piece I haven't noticed a replacement for is Control.

>What about development tools, like BASIC-O9 (I think that is right)?

Their's a fair bit of that.  Full fledged programming languages are
somewhat rare, simply because it's a pain in the a$$ writing compilers
by hand, alone.

>What about applications and other useful tools?

Lots of usefull tools, not many Free applications.  We've had some
recent discussion about that, too.  It's a matter of how large a
project can a lone programmer complete in a reasonable amount of time
when he's not being paid for it.  

>In short - I would be interested in seeing a FAQ or something for 

I have to admit, our FAQs are extremely outdated.  Trying to answer
technical questions without full details is somewhat difficult. ;-)

>Also, info on doing something similar using emulators 

Don't look at me there, I'm a fan of the REAL HARDWARE.

>I think this would be a useful resource everyone interested in OS-9. 

Not to turn this into an ad for NitrOS-9, but, for reasonably common
CoCo configurations, the instructions on nitros9.org are a good
starting point.  And if your setup is that weird, you're probably not
just starting out with a CoCo.  

Willard
-- 
Willard Goosey  goosey at sdc.org
Socorro, New Mexico, USA
"I've never been to Contempt!  Isn't that somewhere in New Mexico?"
   --- Yacko