Path: utzoo!attcan!uunet!cs.utexas.edu!usc!brutus.cs.uiuc.edu!uakari.primate.wisc.edu!aplcen!haven!uvaarpa!mcnc!rti!bcw From: bcw@rti.UUCP (Bruce Wright) Newsgroups: comp.sys.ibm.pc Subject: Re: rainbow problems Summary: Rainbow isn't PC compatible! Message-ID: <3304@rti.UUCP> Date: 2 Dec 89 17:52:15 GMT References: <4438@eagle.wesleyan.edu> Organization: Research Triangle Institute, RTP, NC Lines: 124 In article <4438@eagle.wesleyan.edu>, dkonerding@eagle.wesleyan.edu writes: > Hello, folks. I've got a small problem with a Rainbow. > There's a 10MB HD that autoboots. The machine came with MSDOS 2.05, > and I've installed that on the HD. However, when I insert a MSDOS 3.3 disk, > and try to run a program, it boots me to an error screen, or just plain > returns me to the prompt. I assume that is because MSDOS 2.05 itself > cannot run programs that new. However, using 2.05's sys command, I was > able to install 3.3 DOS on the HD-- however, the Rainbow "does not > recognize it". Therefore, I cannot run (I assume) anything that does > not work with old DOS). I'm not quite sure what the configuration of the Rainbow is from the description you've given, but I can tell you a few things about the machine that will explain the problems you're having. First of all, the Rainbow is not PC compatible. It does run MS-DOS, but that's because it has a specially customized version of MS-DOS that knows how to deal with the hardware differences. For example, screen memory is organized differently and in a different location, graphics are totally different from PC graphics, the disk interface can only be described as odd (the floppy driver actually runs on the Z80 rather than the 8088), the serial I/O is done in a completely different way, the ROM-BIOS is different, etc, etc. Forget running DOS 3.3 on it - the standard DOS 3.3 is expecting a PC compatible, and the Rainbow just isn't. In many ways it's not a bad machine (especially for its time - 1983; one of the nice things you can do with it is put up to 896K of memory on the machine - all of it useable by MS-DOS: the limit on the IBM-PC is that the video memory sits smack in the middle of your address space and limits you to 640k) but it's different from most machines you see today and it's dated. Secondly, the floppy drives on the Rainbow are not 360K DSDD floppy drives - they are 400K SSDD 96TPI drives. This is an odd format that isn't very popular any more - though the machine can read (and sometimes write, if you are lucky) SSDD 180K floppy drives. I am not sure why the machine is running MS-DOS 2.05. The version that was normally run with a hard disk drive on the Rainbow was 2.11. It's possible that the hard disk isn't a DEC or DEC compatible hard disk (there were a couple made for the machine that didn't attach into the machine in the standard way - I think Convex made one of them - and they may not require MS-DOS 2.11). In any event, none of this helps you get things running. As far as I know, there isn't an MS-DOS 3.3 for the Rainbow, but there is an MS-DOS 3.1. It is available from the major systems house that still produces new Rainbow products, Suitable Solutions. They can also sell a copy of Code Blue, which is a software product that provides >nearly< complete IBM-PC emulation as long as the program you're running doesn't do anything too hardware-dependent (it DOES provide video memory emulation, which is the major hardware dependency in most non-communications PC software). Also available is a floppy disk drive that can read and write standard 360K floppies, and one that will read and write 720K 3.5" floppies; extra memory cards (the Rainbow didn't use a standard PC bus and won't take normal PC memory, you need a special card. I can't tell from your stated configuration whether you have one already or not. If you do, you can just add standard 64K or 256K memory chips to it, though you may need to adjust some of the jumpers on the card to tell it what kind of chips you are using); Windows for the Rainbow; and a 286 accelerator card. Their address is: Suitable Solutions 1700 Wyatt Drive, Suite 12 Santa Clara, CA 95054 408-727-9090 Their prices are somewhat above the PC-clone prices but not greatly so; they are also extremely reputable people to deal with. You can also often find used Rainbow equipment from places that sell used DEC equipment such as Newman or Midwest or Brookline. You might be able to find them in something like Computer Shopper or ask around a local college or other DEC shop - their catalogs are everywhere at such a place, and their prices on used Rainbow hardware will be lower than Suitable Solutions'. I'm not sure I would recommend upgrading the machine to a more reasonable configuration (memory especially seems small by modern standards) - it depends on whether you want to live with the compatibility problems or not. It can still be a very nice and useable machine, but even with MS-DOS 3.1 and Code Blue, you still can't just drop any random PC program onto it and expect it to work. As for word processors, there are four things you could try: 1. It is likely that if you get Code Blue and MS-DOS 3.1 from Suitable Solutions, that your favorite PC word processor will run on the Rainbow if you can convert it to the appropriate disk format (you may or may not want to consider adding a 360 or 720K floppy drive). Word processors (except Microsoft Word, I don't know if it can be made to run on the Rainbow but it is notorious for being hardware dependent) tend to work pretty well in this environment. 2. You could probably locate a copy of SEDT from a DEC-related bulletin board; this is a nice screen editor that is public domain. Check a DEC-related newsgroup such as comp.sys.dec.micro, if you have access to usenet; if not and you can't locate any mail me and I will try to locate one in your area. 3. EDT from Boston Business Computing, which is a pretty nice screen editor but which costs real money ($300). Boston Business Computing Riverwalk Center 360 Merrimack Street Lawrence, MA 01843 4. VEDIT from CompuView, which is a screen editor with a TECO-like macro language. I don't know the cost - I think they have several versions (VEDIT, VEDIT/PlUS) the last I knew, with a fairly steep price curve (like maybe $100 for VEDIT, $250 for VEDIT/PLUS). CompuView 1955 Pauline Blvd Ann Arbor, MI 48103 One way or another, unless you can make do with nothing but SEDT, you will either have to spend some money on the machine or sell it and buy a PC clone. Be forewarned however that it doesn't have a great deal of resale value ... probably under $500; a Rainbow with 128K of memory, monochrome monitor, no graphics board, and no hard drive sells for around $200-$300 and less if you sell to a reseller such as Newman. I don't know how much the hard drive would add; if it's DEC it might add a bit more, but it sounds like it's third-party, so my guess is that the machine is worth maybe $400 retail (if you can find someone who still uses Rainbows). Good luck. Bruce C. Wright