Northstar Horizon

Re: "But you will have a bit of a "chicken and egg" problem - the NorthStar disks are hard-sectored, which means that you can only make them on a system with the NorthStar controller. Unless you have other N* systems kicking around you will have to use the Horizon. But the Horizon has no front panel, or other means to easily bootstrap code into it other than the disk drive." Install the North Star disk controller card into a CP/M system configured such that there are no memory or I/O port conflicts. Then you can assemble source code of the NorthStar DOS using CP/M's ASM, and load it into RAM using DDT. There are routines in the NorthStar ROM (which will now exist in the CP/M system) for formatting a disk and writing out RAM to the diskette. It's possible for a NorthStar controller and a typical CP/M soft sector controller to co-exist in the same system at the same time, if you resolve any I/O port and memory conflicts. This allows the use of CP/M and all of it's facilities (in particular, source code editors, ASM and DDT) to create a first NorthStar diskette. ------------------------------ Message: 8 Date: Sat, 25 Nov 2006 06:56:50 -0500 From: "Dave Dunfield" <dave06a at dunfield.com> Subject: Re: Northstar Horizon To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <200611251101.kAPB1t0K026282 at hosting.monisys.ca> Make sure you have the disk controller designation right - My single density NorthStar controllers are called MDC-An and the double density ones are called MDS-AD(n). You need to figure out if you have a single density or double density controller in order to determine which boot disk you need. If it's MDS, I think it should be double-density, but I expected the latter part to be "-AD3". I have photos of both controller types on my site the difference between a single-density and a double-density is easy to see . check documentation. I have a lot of NorthStar material and documentation on my site - much of it in the Altair section (One of my Altairs has a NorthStar controller). on I have many images for both single and double density Horizon systems on my site - if It's SD, your choices are NorthStar DOS and my own DMF system. If DD, the choices are NorthStar DOS, CP/M and UCSD Pascal. But you will have a bit of a "chicken and egg" problem - the NorthStar disks are hard-sectored, which means that you can only make them on a system with the NorthStar controller. Unless you have other N* systems kicking around you will have to use the Horizon. But the Horizon has no front panel, or other means to easily bootstrap code into it other than the disk drive. If you happen to have an S-100 ROM card, you could use it to bootstrap the Horizon. I've got a very simple monitor that you can use to bootstrap in the NorthStar tools archive. Also - in case you are not aware, the 10 sector diskette are physically different than a typical soft-sector diskette (11 sector holes instead of one) - you need 10-sector diskettes for the Horizon which can be difficult to find. Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html ******************