Looking for Horizon CP/M boot floppy

[n0hj]

As a follow up, I was able to bring up the Horizon slowly on my variac
without any cards, then did the same with cards. Now it seems to be
looking for a floppy at bootup. I've ordered some hard sector
floppies but am in search of a bootable CP/M floppy, perhaps with
Dave's utilities to transfer other Northstar images. If I can only
start with a NSDOS bootable floppy, then I will go that route.

Does any Horizon owner have the time and ability to loan me a bootable
floppy in return for expenses?

Thanks,
John

[Dave Dunfield]

n0hj <john.ev...@gmail.com> wrote:

My transfer utility runs under NorthStar DOS - but once you get it going, you
can use it to make CP/M images from the system-disk library.

The trick with the Horizon is getting code into it in the first place - since
there is no front panel etc. There is a 1K ROM socket on the CPU card,
and you can put a tiny monitor in there (I can provide a rudimentary
monitor in 512 bytes that requires NO ram at all - good for debugging
RAM boards) - once you have this running, I have a utility that will
load N*DOS with the transfer utility into RAM by "typing" it into the
monitor - then you can launch it and if all goes well, write out a
bootable diskette image. All these tools are included with my
Horizon simulator on the web site.

Dave

--
dave09@ Low-cost firmware development tools: www.dunfield.com
dunfield. Classic computer collection: www.classiccmp.org/dunfield
com

[n0hj]

Well, the booting wasn't as simple as cleaning the drive heads and
seeing if Lifeboat CP/M would take. I get about ten disk seeks during
boot but no joy at this time. I plan a two pronged approach now - see
if cleaning and lubing the TM-100-2a drives helps and working to get
Dave's monitor prom installed on the CPU card to test memory and
transfer disk images and software.

I plan to burn Dave's 1K monitor code into a 2732 PROM (configured to
look like a 2708) since the only programmers I have access to will
only handle 2716s and above.

The Horizon I have has Quad Capacity drives and there was some
question as to whether it would boot to a single-sided floppy, but
unless I am mistaken, I don't think this should be an issue.
Cleaning, lubing, and a more careful visual inspection may help, too.
I also plan to go thru the manuals and do an ops check on the CPU and
controller boards to make sure they at least meet the manual checks.

Such fun !!! Film at eleven :)

John