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• General Information
• Transfer
• cpmtools
• Downloads
• Information
• References

As my former professor at the "Institute of Fluid Mechanics" at the University of Hannover used to say, "The biggest problems with programs and computers are the interfaces." And this is especially true for the North Star Horizon. Even normal floppy drives with soft-sectored floppy disks are a problem. But hard-sectored floppy disks take the cake.

I am not exaggerating when I say that today there are probably only a handful of experts worldwide who are really familiar with these old computers and are still active today. I am NOT one of them; I only do research and re-enact things. And as you can see, with success.

As a representative, I would like to name just "one" person at this point: MIKE DOUGLAS. He runs the site: DeRamp.com. During my project I was or I am in contact with him and he gave me a lot of tips. Thanks to Mike!

If you have ever worked with Mike Douglas' PCGET and PCPUT programs, you will find that the FLOP2PC and PC2FLOP programs are just as easy to handle.

PCGET & PCPUT
------------------------
Copy file to N* from PC:
N*    <- PC
pcget -- send

Copy file from N* to PC:
N*    -> PC
pcput -- receive

With the first mentioned you can copy a single file with the XMODEM protocol from another PC to the North Star or the other way around. And if you are now confronted with the hen - egg problem, no problem either. This can be solved with PIP.

With the latter two you copy a complete image from the floppy disk to the PC or the other way around; again via the serial interface with the XMODEM protocol. It is like DOS RawWrite but only serial.

PC2FLOP & FLOP2PC
-----------------------------------------
Write image from file on PC to N* floppy:
N*      <- PC
pc2flop -- send

Write image from N* floppy to file on PC:
N*      -> PC
flop2pc -- receive

To be fair, though, I would like to mention that there is a similar program package from Dave Dunfield for the North Star. But the program NST.COM by Dave Dunfield works only with the North Star DOS.

Using Both Serial Ports on a Horizon

When using the first serial port for console and file transfer, I often got transmission problems with XMODEM. The connection was established correctly but then nothing happened, no data was transferred.

So I thought, why not use both ports? The first as the normal console and the second exclusively for file transfer with XMODEM. What can I say? It works. I use Windows 10 with two instances of TeraTerm. The connection is made via two USB serial cables and two Prolific PL2303GC USB to Serial Bridge Controller.

Problems

The file or image transfer via works fine with a real floppy disk drive but I have always a problem with the DREM.

When I start PCPUT on the DREM drive A, for example, then either a reset to the PROM monitor occurs or I get the message: "Can't Open File". Which file?

But on the real drive C, here a Tandon TM100-2, everything works as it should.

On the PC (Windows, macOS, Linux) you can of course also work with the cpmtools by Michael Haardt and the NSI images. NSI files are simple raw dump images, nothing special. You can list, add and erase files in the image. Copy these changed images to your DREM and you can use them on the N*.

# Classic build and install the cpmtools on macOS.
% ./configure
% make all
% sudo make install

# Homebrew install of the cpmtools on macOS.
# I prefer this way because Homebrew uses symlinks.
% brew install cpmtools

# You have no Homebrew installed?
# Run the scripts in the Terminal and watch the displayed messages.
% /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
% (echo; echo 'eval "$(/usr/local/bin/brew shellenv)"') >> /Users/USERDIR/.zprofile
% eval "$(/usr/local/bin/brew shellenv)"

Here a little help file and some more info on N* diskdefs. Here is my Homebrew installation logfile; this is how the installation should ideally look.

--------------------------------------------------------------------------------
Source: Mike Douglas and Larry Kraemer; VCF, 2018
--------------------------------------------------------------------------------
# Northstar Micro-Disk System MDS-A1 87
# SSSD 48 tpi 5.25" - 256 x 10
#
diskdef mdsad87
  seclen 256
  tracks 35
  sectrk 10
  blocksize 1024
  maxdir 64
  skew 1
  boottrk 3
  os 2.2
end

# Northstar Micro-Disk System MDS-A-D 175
# SSDD 48 tpi 5.25" - 512 x 10
#
diskdef mdsad175
    seclen 512
    blocksize 1024
    tracks 35
    maxdir 64
    boottrk 2
    sectrk 10
    skew 5
    os 2.2
end

# Northstar Micro-Disk System MDS-A-D 350
# DSDD 48 tpi 5.25" - 512 x 10
#
diskdef mdsad350
   seclen 512
   blocksize 1024
   tracks 70
   maxdir 64
   boottrk 2
   sectrk 10
   skew 5
   os 2.2
end

--------------------------------------------------------------------------------
accessing a single sided, double density (SSDD) image
--------------------------------------------------------------------------------
% cpmls -f mdsad175 -D CPM-2-23DQ-24K-SSDD-Lifeboat.NSI

Name    Bytes   Recs  Attr 
------------ ------ ------ 
ASM     .COM     8K     64    
CONFIG  .COM     6K     48    
COPY    .COM     4K     30    
...
USER    .ASM    11K     82    
XSUB    .COM     1K      6

28 Files occupying 137K, 26K Free.

--------------------------------------------------------------------------------
copy a file from image to pc
--------------------------------------------------------------------------------
% cpmcp -f mdsad175 CPM-2-23DQ-24K-SSDD-Lifeboat.NSI 0:READ-ME.DOC .

...
READ-ME file for CP/M2 on North Star
Last updated:  July 22, 1981

Current CP/M2 version is 2.23a DQ - Jul 22, 1981

This file contains up to date information that is not yet
in the User's Notes.  It should always be read immediately
whenever your CP/M is updated.
...

--------------------------------------------------------------------------------
accessing a single sided, single density (SSSD) image
--------------------------------------------------------------------------------
% cpmls -f mdsad87 -D CPM22b14-48K-SDC-HORIZON.NSI 
     Name    Bytes   Recs  Attr     update
------------ ------ ------ ---- -----------------
ASM     .COM     8K     64    
COPY    .COM     2K     14    
DDT     .COM     5K     38    
DUMP    .COM     1K      4    
ED      .COM     6K     48    
LOAD    .COM     2K     16    
MOVCPM  .COM    11K     84    
PCGET   .COM     1K      7    
PCPUT   .COM     1K      7    
PIP     .COM     8K     58    
STAT    .COM     6K     42    
SUBMIT  .COM     3K     17    
SYSGEN  .COM     1K      8    
USERHRZ .ASM     8K     58    
   14 Files occupying     63K,      15K Free.
   
 
--------------------------------------------------------------------------------
copy a file from image to pc
-------------------------------------------------------------------------------- 
% cpmcp -f mdsad87 CPM22b14-48K-SDC-HORIZON.NSI 0:USERHRZ.ASM .   

...
;----------------------------------------------------------------
; USERHRZ.ASM		MAR  2, 1981
;
;  Updated 11-13-15 by M Douglas for use with
;    CP/M 2.2 for single density North Star controller
;
;  This USER AREA is for a Horizon computer
;  as used with CP/M 2.2 for single density North Star
;
...

Here you will find all my gathered downloads for the North Star Horizon.

Here you will find all my gathered downloads for the North Star Horizon.

1. (↑) .....

--> Go to Part 0: Information
--> Go to Part 1 : Restoration & (my) S-100 Boards
--> Go to Part 2 : Hard-Sectored Disks
--> Go to Part 3 : File and Image Transfer
--> Go to Part 4 : PROM Modification
--> Go to Part 5 : History
--> Go to Part 6 : RAM
--> Go to Part 7 : S-100 Bus
--> Go to Part 8 : Capacitors
--> Go to Part 9 : Virtual Horizon
--> Go to Part 10 : S-100 Boards